Plenary Opening Lecture
1 From sequence to phoresy – molecular biology in acarology
Hans
Klompen
Ohio State University
Acarology Collection, Museum of Biological Diversity, 1315 Kinnear Road, Columbus,
OH 43212, USA.
E-mail:
klompen.1@osu.edu
Phylogeny and Taxonomy of Acari
2 Systematic relationships of Lohmanniidae (Acari: Oribatida)
Roy A.
Norton
p. 9
Lohmanniidae is a moderately
diverse family of macropyline oribatid mites that is usually grouped with taxa
having
opisthonotal glands, even
though they themselves lack these glands. Morphological traits are examined for
evidence
that lohmanniids are instead
members of Enarthronota, particularly the superfamily Hypochthonioidea. Six
traits are
consistent with membership in
Enarthronota, eight support a relationship with Hypochthonioidea and its close
outgroup
Arborichthoniidae, seven support
membership in Hypochthoniidae, and five others support a sister-group
relationship
with its subfamily
Nothrolohmanniinae. Two alternative classifications are suggested to
accommodate this
relationship.
Key words: Oribatid
mites, Enarthronota, Hypochthoniidae, Hypochthonioidea, Malacoangelia, Nothrolohmannia
Gerd Weigmann
Institute of Biology, Zoology, Freie Universität
Berlin, Koenigin-Luise-Str. 1-3, 14195
E-mail:
weigmann@zedat.fu-berlin.de
p. 17
Occasionally, specimens of
oribatid mites have abnormal asymmetric characters, e.g., regarding notogastral
setation
or the porose areas of the
octotaxic system, similar to those in other more or less related taxa, or
similar to those in
ancestors. Exemplarily,
anomalies in specimens of Scheloribatidae and Phenopelopidae are presented. A
model is proposed
involving chains of regulatory
genes that explains evolutionary changes within branches of poronotic Oribatida
as well as the notogastral
anomalies discussed. This model may contribute towards a revised strategy for
taxonomy
and phylogenetical
systematics.
Key words: Phylogenetic
systematics, taxonomy, regulatory genes, Scheloribatidae, Phenopelopidae
Sergey
Mironov1 & Georges Wauthy2
1Zoological Institute,
2Institute royal des Sciences
naturelles de Belgique, rue Vautuer 29, B-1000,
p. 23
Cladistic reconstruction of
phylogenetic relationships within the Pteroherpus generic group, consisting of the genera
Dicrurobius, Micropteroherpus, Pteroherpus, and Vanginyssus, has been carried out, here,
for the first time. This
analysis was based on 46 morphological
characters and 29 operational taxonomic units, including 21 species of the
Pteroherpus group (ingroup), eight species
representing three pteronyssid genera known from passeriforms and piciforms
(close outgroups), and two
species of the family Avenzoariidae (distant outgroups). Maximum parsimony
analysis
confirmed monophyly of the Pteroherpus group and four of its genera.
The analysis also revealed four distinct lineages
within the genus Pteroherpus that we treat as species
groups: hoplophorus,
diploplax, nicator, and josephi. The
Pteroherpus group displays two contrasting
tendencies in morphological modifications: (1) reduction of shield areas
in the posterior part of the
female opisthosoma by splitting the hysteronotal shield into fragments and
decreasing
their size; this trend has
been realized to various extents in all genera of the group, and (2)
development of additional
sclerotization in the sejugal
area in both sexes of the most derived species of the holoplax and diploplax groups of
Pteroherpus. Based on phylogenetic
relationships within the Pteroherpus generic group and among their avian hosts,
and on parasite-host
associations, we conclude that co-speciation with their hosts was the main mode
of diversification
– although in a few cases host
shift has taken place.
Key words: Feather
mites, Pteronyssidae, Pteroherpus group,
phylogeny, host associations, host shift, Passeriformes
Jan
Mourek1,2 & Ladislav Miko3
1Department of Zoology,
E-mail:
jan_mourek@yahoo.co.uk; 2Department of Biology and
Environmental Education,
Education, MD Rettigové 4,
CZ-116 39 Prague 1,
Avenue de Beaulieu 9, BE-1160
Brussels, Belgium
p. 31
The famulus is a specialised seta
on the dorsal side of the tarsus of the first pair of legs in acariform mites.
It has various
shapes, but a stable location
within the whole group. In the oribatid family Damaeidae, two states of famulus
are
known: emergent and sunken.
The emergent famulus is a simple short seta with fully emergent insertion. It
is present
in the adult of all known
Damaeidae and in immature stases of many damaeid genera. The sunken famulus is
reduced in size and submerged
in a fovea with an elevated rim, so that only its tip is visible. In this
study, the ontogenetic
development of the famulus in
selected Central European damaeid species, namely Damaeus (Adamaeus) onustus,
D. (Paradamaeus) clavipes, Epidamaeus tatricus, Spatiodamaeus verticillipes, Kunstidamaeus lengersdorfi, and
Belba compta, was studied with light and
scanning electron microscopy and compared with that of Gymnodamaeus
bicostatus (Gymnodamaeidae). Literature
data on the ontogeny of the famulus in Damaeidae are summarized and the
significance of the famulus as
a phylogenetic marker is discussed. In agreement with previous studies, adults
of all
studied members of Damaeidae
had an emergent famulus. The immatures of all studied members of Damaeus sensu
lato, except for E. tatricus, had a sunken famulus, whereas
the immatures of B. compta had
an emergent famulus.
Immatures as well as adults of
G. bicostatus had a sunken famulus. In
contrast to Norton’s phylogenetic hypotheses,
all immature stases of E. tatricus possessed an emergent famulus,
similar to B. compta.
Therefore, either the monophyly
of Epidamaeus is questionable, or, more
likely, reversal to a plesiomorphic state occurred in E. tatricus.
Key words: Famulus,
ontogeny, morphology, Oribatida, Damaeidae, Epidamaeus tatricus, SEM
Stefan
Wirth
Museum für Naturkunde Leibniz,
Institut für Evolutions- und Biodiversitätsforschung an der
Humboldt-Universität zu
p. 37
The feeding behavior of Bonomoia opuntiae Wirth was studied in
comparative studies on other species of
Histiostomatidae, a large
monophyletic subgroup of the Astigmata. Bonomoia opuntiae was collected from rotting
pieces of Opuntia sp. in the Mediterranean area
and is morphologically derived, especially with respect to the mouthparts,
which are distinctly modified
relative to the typical histiostomatid gnathosoma. Distal pedipalps and distal
chelicerae
are adapted so as to pick up
pieces of the natural microorganism cover from the ground. To enable feeding on
this substrate, the distal
chelicerae are spoon-shaped and projected inwards and they can be moved against
each
other like a clasp organ. This
mite B. opuntia was
frequently observed to move into muddy substrates and to swim in
more watery habitats. The leg
movements supporting locomotion in these habitats are quite unusual: Each pair
of legs
I and II move from anterior to
posterior position, but the two pairs do so asynchronously. When legs II move
to the
anterior position over legs I,
legs I just start to move backwards. This mode of locomotion is termed
‘leg-crossing’. In
the field this mite was found
to live syntopically with Histiostoma sp. Probably due to the unusual adaptations to use
other food resources, B. opuntiae survives under laboratory
conditions even in the presence of Histiostoma sp. This is
striking, because most
observed histiostomatid species show very similar food preferences and feeding
mechanisms
in the laboratory, so that
they are strong food competitors and cannot be cultured in mixtures.
Key words: Astigmata, Bonomoia opuntiae, feeding behaviour, food
competition, Histiostoma sp.,
Histiostomatidae,
SEM
M.-S.
Tixier, S. Guichou & S. Kreiter
Ecole Nationale Supérieure Agronomique
/ Institut National de la Recherche Agronomique, Unité d’Ecologie animale et de
Zoologie Agricole, Laboratoire
d’Acarologie, 2 Place Pierre Viala, 34060 Montpellier cedex 01, France.
E-mail: tixier@supagro.inra.fr
p. 41
To determine the suitability
of several molecular markers for taxonomic studies on the family Phytoseiidae,
5 nuclear
and 3 mitochondrial DNA
fragments were sequenced for several populations, species, genera, and
sub-families. DNA
sequences were obtained
experimentally or taken from Genbank. Lowest nucleotide divergence was found
for the
two 18S fragments. No
variability was observed between populations of one species (Neoseiulus californicus),
between species of one genus,
and between two genera of one sub-family. Variation between two sub-families
was
very low (0.6-1.2%). Poor
variability was observed for the two 28S fragments between and within
sub-families.
Variability was higher for
sequences of the fragment ITS-5.8S (intra-genus, 3-7%; inter-genera, 17-20%;
inter-subfamily,
29-33%). Variation between
intra-species populations was very low for this DNA fragment. Higher nucleotide
divergences
were obtained for the
mitochondrial fragments. For the 12S fragment, the nucleotide divergence rate
between
two Neoseiulus species was 10%, 25-33%
between genera of the same sub-family, and 27-33% between two sub-families.
For the fragments of COI,
variability between species of a single genus was ca. 20%. Nucleotidic
divergence of
species belonging to two
genera was 26-36% within, and 26-43% between sub-families. Intraspecific
variation was low
(0-0.4%). The 18S and 28S
regions seem to be too conserved for phylogenetic analysis within Phytoseiidae,
and would
be more suitable for deeper
phylogenetic analysis. The mitochondrial fragments are too divergent for robust
alignments
and phylogenetic analysis
between genera of the family, and would be more suitable to assess within-genus
systematic studies and species
discrimination. The ITS-5.8S fragment seems adequate for phylogenetic analysis
within
sub-families. However,
nucleotide divergence is too high for assessing relationships between
sub-families.
Key words: Phytoseiidae,
taxonomy, molecular markers, mt-DNA, nuclear DNA
8 The genus Dermanyssus
(Mesostigmata: Dermanyssidae): history and species characterization
L. Roy
& C. Chauve
Laboratoire de Parasitologie
et Maladies Parasitaires, Ecole Nationale Vétérinaire de Lyon, 1 avenue
Bourgelat, 69280
Marcy-L'Etoile, France. E-mail:
l.roy@vet-lyon.fr
p. 49
The genus Dermanyssus Dugès, 1834 (Mesostigmata:
Dermanyssidae) includes hematophagous mites that are
ectoparasites of birds. Over
the years, the number of species included varied greatly: 56 or more species
have once
been classified in this genus,
but after the last review by Moss in 1978 only 18 species remained; presently
there are
23. Major changes in genus
definition drastically reduced the number of species included, involving not
only the establishment
of synonymies, but also many
changes in systematic position based on literature data (Roy & Chauve,
2007).
However, in 2007 the species
definition is not yet clear. We present an overview of the current systematic
position of
all 56 species that were once
included in this genus. In addition, we review host specificity and geographic
distribution
of Dermanyssus species, and we discuss
morphological characters posing problems in species characterization.
Key words: Mesostigmata,
Dermanyssus, morphological characters,
systematics
Morphology of Acari
Gerd Alberti, Antonella di Palma1, Gerald W. Krantz2 & Czesl/aw Bl/aszak3
Ernst-Moritz-Arndt Univ, Zool
Inst and Museum, J.-S.-Bach-Str. 11/12, D-17489
de; 1Univ Studi di Foggia, Dipto
Scienze Agroambientali, Chimica e Difesa Vegetale, Via
Dept Animal Morphology,
Umultowska 89, 61-614 Poznan´,
p. 59
Females of Dermanyssina
display a reproductive system composed of a region involved in egg production
and laying
and another involved in sperm
reception and likely storage. This second region is called the sperm access
system, and
it is related to a peculiar
sperm transfer mode known as podospermy. Males have the chelicerae modified as
gonopods
which possess a peculiar
process on the movable digit, the so-called spermatodactyl, which is used for
sperm transfer.
In Veigaiidae, males are
rarely, exceptionally, or never found, and some species are considered to
reproduce
parthenogenetically. Known
veigaiid males have spermatodactyls, sometimes of extraordinary length. The
conspecific
females have so-called spiral
organs located behind coxae IV. It is likely that these organs, not known from
other
gamasid mites, represent the
veigaiid sperm access system. In the present study, first ultrastructural
details on these
peculiar organs are given
comparing a bisexual species (Veigaia sp.) with two species in which males are extremely
rare (V. nemorensis and V. cerva). Each of these structures is
composed of a major tube starting from the opening, a
vesicle-like region, and
several minor tubes. In general it is considered to be derived from an
entapophysis. Muscles
attach to the minor tube
region. A general similarity to the phytoseiid type of sperm access systems may
be noted.
But preliminary observations
on the whole genital system of both female and male veigaiids also reveal a
resemblance
to the genital system in
Parasitina. Whether these findings may challenge the current status of
Parasitina and/or
Dermanyssina will require
further investigations.
Key words: Dermanyssina,
entapophysis, fine structure, Michael’s organ, Parasitina, podospermy
Andrew
B. Shatrov
Zoological Institute of the
p. 65
The integument of adult Hirsutiella zachvatkini and Euschoengastia rotundata (Trombiculidae), Platytrombidium fasciatum
and Camerotrombidium pexatum (Microtrombidiidae), Piona conglobata (Pionidae), and Teutonia cometes
(Teutoniidae) (water mites)
were investigated by transmission and scanning electron microscopy. The soft
integument
of adult trombiculids is built
up of specific epithelial respiratory tissue, provided by long, branched
mechanoreceptor
setae organized as neotrichia
functioning as a plastron. The seta pits with clear cuticle are surrounded by
cuticular folds
with tightly packed ridges
composed of an electron-dense substance. The underlying epidermal tissue is
formed of separately
scattered compact epidermal
cells intermingled with large polymorphic so-called ‘intra-epithelial cells’
with
clear cytoplasm devoid of
organelles. The integumental folds with the intra-epithelial cells filled with
metabolic and
sorptional water are thought
to function as air gills, which selectively absorb and transport oxygen from
the outside to
internal tissues. In
microtrombidiids, also an internal cuticular meshwork is expressed, formed of
thick electron-clear
strands immersed into the
epidermis and crossing at right angles. This meshwork is separated from the
external cuticle,
comprising a thick lamellar
procuticle covered by thick electron-light epicuticle. Flat uniform epidermal
cells contain
numerous pigment granules. In
water mites, a very thick lamellar procuticle penetrated by pore canals is
covered
by a thick dense epicuticle. Setae
are arranged following the orthotrichous type. The epidermal layer underlying
the
cuticle consists of flat
uniform epithelial cells devoid of pigment. The organization of the integument
in stocks of
Trombiculoidea and
Trombidioidea appears strongly apomorphic, whereas it is plesiomorphic in water
mites.
Key words: Epidermis,
soft cuticle, ultrastructure, Trombiculidae, Microtrombidiidae, Pionidae,
Teutoniidae, Parasitengona
Harry
Smit & Gerd Alberti1
Zoological Museum,
E-mail: smit.h@wolmail.nl; and
1Ernst-Moritz-Arndt University,
Zoological Institute and Museum, J.-S.-Bach-Straße 11/12,
D-17489
p. 71
The water mite family
Pontarachnidae Koenike is the only family of the water mites (Hydrachnidia)
occurring in the
marine environment. Two genera
of this family are known, Pontarachna Philippi and Litarachna Walter. Until now, this
has been one of the least
known water mite families. This paper gives an overview of our knowledge on
this enigmatic
family. For the first time,
ultrastructural details are reported based on a study of Litarachna communis. Peculiarities
of the cuticle, the so-called
wheel-like acetabula, the glandular systems, the digestive system, the
dorsomedian excretory
organ, and the male genital
system are reported.
Key words: Hydrachnidia,
Litarachna, morphology, Pontarachna, ultrastructure
12 Two novel adaptations for
dispersal in the mite family Histiostomatidae (Astigmata)
Norman
J. Fashing
Department of Biology,
p. 81
Two unique morphological
adaptations for phoretic attachment to arthropod hosts by deutonymphs of the
family
Histiostomatidae are
described. The deutonymphal attachment plate of Creutzeria from
has well developed suckers for
attachment to smooth cuticle, as well as modifications that allow for
‘grasping’. The
conoidal setae are located on
the posterior margin with apices modified into trifurcate, claw-like
projections. Although
the modified conoids are
retracted and separated when the sucker plate is relaxed and flat, deutonymphs
can fold the
sucker plate medially and
simultaneously extend the modified conoids. This action causes the medial
conoids to
merge and interlock their
trifurcated tips above a furrow formed from the plate fold. In all probability,
these deutonymphs
are both entomophilous and
pilicolous. The deutonymphal attachment plate of Ceylanoetus is enlarged,
covering a significant portion
of the paraproctal region. Although it has typical conoidal setae, the anterior
suckers are
greatly reduced and the medial
suckers vestigial. The idiosoma has a truncated rear margin bearing flap-like
lateral
extensions that curve
ventrally and surround the attachment organ. When dispersing, a deutonymph
wraps the flaplike
lateral extensions of its
idiosoma around the anterior margin of the beetle host’s tibia, thereby
completely surrounding
it. Although the ridged
conoids probably help the deutonymph to hold its position, the ancestral
attachment
method by means of suckers has
been lost in this genus. The term ‘crurophilous’ is proposed for this unique
form of
deutonymphal attachment.
Key words: Creutzeria, Coelanoetus, Histiostomatidae, deutonymph, hypopus, dispersal
Kerstin
Klien & Manfred G. Walzl
Department of Theoretical
Biology,
E-mail: kerstin.klien@gmx.at
p. 85
The anatomy of the
receptaculum seminis and ovary of female Sancassania berlesei (Michael) has been studied by
light and scanning electron
microscopy. Special attention has been given to the illustration and
localisation of sperm
in these organs after
copulation. Therefore the genital tracts of individually reared females have
been dissected after
their first copulation. For
the illustration of aflagellate spermatozoa in receptaculum seminis, ovary and
testes, differential
interference contrast
microscopy and DAPI fluorescence staining were applied.
Key words: Reproductive
system, receptaculum, ovary, testes, sperm, DAPI-fluorescence
Biogeography and Biodiversity of Acari
14 Heterozerconidae: A
comparison between a temperate and a tropical species
Beverly
S. Gerdeman & Rufino Garcia
Washington State University,
Mount Vernon Northwestern Washington Research & Extension Center, WA
98665-9752 USA.
E-mail:
mitehunter1@hotmail.com, prostigman7@hotmail.com
p. 93
A comparative field study was
performed between a tropical species and a temperate species of
Heterozerconidae
(Acari: Mesostigmata). The
temperate species, Narceoheterozercon ohioensis Gerdeman and Klompen, is a long-lived
mite, which shares an
intricate relationship with its host millipede, Narceus annularis (Rafinesque) (Diplopoda:
Spirobolida: Spirobolidae).
The phenology between these mites and their millipede host shows coinciding
periods of
oviposition and mating, with
both producing a single generation/year. Although the adults appear to feed on
the exudates
of the millipedes and are
rarely separated, the immatures, developing during the summer, have adapted to
a
free-living, predatory
lifestyle within the millipede ‘nest-sites’ of fallen logs. In contrast, the
relationship between a
Philippine heterozerconid, Allozercon sp., and its host millipede
(Diplopoda: Spirobolida: Rhinocricidae) is less constrained.
In these tropical species,
both the millipedes and their associated heterozerconids produce multiple
generations/
year. Millipede mating is no
longer a synchronous event and immatures are found throughout the year in
localized
accumulations of millipede
frass, beneath the forest litter.
Key words: Heterozerconidae,
Mesostigmata, Narceoheterozercon ohioensis, Allozercon, Diplopoda, Spirobolida,
Narceus annularis,
Rhinocricidae
15 Patterns of diversity in
the Ceratozetoidea (Acari: Oribatida): a North American assessment
Valerie
Behan-Pelletier & Heinrich Schatz1
Biodiversity Program, Research
Branch, Agriculture and
0C6. E-mail:
valerie.behan-pelletier@agr.gc.ca; and 1Institute
of Zoology,
p. 97
Represented globally by eight
families, 91 genera and about 556 species, the Ceratozetoidea is among the most
diverse superfamilies of
oribatid mites. Species of Ceratozetoidea occur in forest, grassland, tundra,
and semiaquatic
habitats. They are found in
all biogeographical regions, but are most diverse at mid to high latitudes in
the Nearctic,
Palaearctic, and Neotropics.
The richness of the group in
species in 32 genera
representing the families Ceratozetidae, Mycobatidae, Chamobatidae,
Zetomimidae,
Humerobatidae, and Euzetidae.
The fauna is dominated by species of Ceratozetes, Trichoribates, and Mycobates, that
represent almost 50% of the
fauna. No species was found in all 12 geographical regions, and Pelopsis bifurcatus and
Punctoribates palustris, the most widely distributed
species in
(55 spp.) of the fauna was
restricted to one region. The trend of increase in number of species with
decreasing latitude
was not supported,
irrespective of longitudinal zone, and southern latitudes had the lowest number
of genera
and species. Almost 42% of
species are shared with other zoogeographical regions, of which three are
cosmopolitan,
viz. Ceratozetes gracilis, C.
mediocris,
and Punctoribates punctum. Species shared with the Palearctic comprise mainly
Amphi-Atlantic, Circumboreal,
and Amphi-Beringian faunal elements. Almost 59% of species are restricted to
the
Nearctic, dominated by species
with Carolinean-Austroriparian and East-Beringian distributions. In contrast
with the
biogeography of other North
American oribatid taxa, that of Ceratozetoidea is strongly influenced by
Beringia.
Key words: Ceratozetidae,
Mycobatidae, Chamobatidae, Zetomimidae, Nearctic, biogeography, distribution,
Beringia
16 Mites occurring in the
canopy of
Julio
Arroyo, Patrick Neville1 & Thomas Bolger
E-mail: julio.arroyo@ucd.ie; 1Coillte Teo.,
Newtownmountkennedy, Co.
p. 105
Following centuries of
deforestation, the area of forest in
hectares annually. However,
the vast majority of the afforestation has been with
occurring in the canopies of
from two arboreal
microhabitats: canopy (leaves and branches) and epiphytic moss. Two of these
species,
Malaconothrus (M.) egregius and Ophidiotrichus tectus, were new records for
record of the genus Ophidiotrichus. Diversity indices and
rarefaction curves demonstrate that oribatid mite diversity
is greatest in both canopy and
epiphyte samples collected at the upper heights. Over 50% of the oribatids
recovered
from the canopy were
Brachypilina and the assemblage was dominated by Phauloppia lucorum and Camisia segnis,
with the remainder of the
species being poorly represented (except Chamobates schuetzi and Eupelops acromios). Of
the 19 species found in the
moss, P. lucorum and
Zygoribatula
exilis were the most abundant
taxa, and C. segnis was
uncommon. In this
microhabitat, 91% of individuals collected were Brachypilina which is not
unexpected. Species richness
is considerably lower than in
similar habitats with native
and Scapheremaeus, were not found in this
study.
Key words: Oribatids,
canopy, arboreal mites, afforestation,
17 Changes of the oribatid
community after a windthrow event
Eileen
Kreibich, Coronula Grauf1 & Sabrina Strauch
Zoological Institute and
Museum, University
E-mail:
eileen_kreibich@hotmail.com; and 1Institute
of Biochemistry and Biology,
and 2, 14469
p. 111
In December 1999 the winter
storm ‘Anatol’ hit the southern coast of the
along the coast. On the Darss
peninsula in north-eastern
and several small ones.
Interestingly, mainly spruce trees were affected. The large windthrow area
measured about
2.5 ha. This area was chosen
to investigate the long-term effects of a windthrow event on the fauna. Repetitive
sampling
was carried out in the first 4
years after the storm (2000-2003) and in the 6th year (2005), and additional
samplings
are planned for the 10th and
the 15th year. To investigate the soil micro-arthropods, in 2000-2003 samples
were taken three times a year,
in spring, summer, and autumn, directly under root plates of two fallen spruce
trees,
in the windthrow area, and in
adjacent pine and spruce stands. Altogether 81,023 specimens of oribatid mites
had
been found in all 4 years. Results
show that the overall abundance of oribatid mites decreased from 2000 to 2002
on
almost all plots – including
the control plot in the fir forest –, before their numbers started to increase
again in 2003.
On the plots underneath the
root plates the abundance of oribatid mites increased continuously over the
years as the
plots were recolonised. The
oribatid mite community on the windthrow area changed over the years, but these
were
quantitative rather than qualitative
changes.
Key words: Oribatid
mites, ecology, windthrow, recolonization, species diversity, mite abundance,
succession
Annett
Wegener & Gerd Alberti
Zoological Institute &
Museum,
E-mail: AnnettWegener@gmx.net
p. 117
In December 1999 a winter
storm largely destroyed pine-spruce stands on the peninsula Darss. After the
decision to
leave the windthrows in the
protected zone to natural succession, a research project was started in 2000 to
investigate
responses of selected endo-
and epigeic arthropod groups to this process. The soil fauna was explored at
two
sites within the windthrow
area and at one site right in front of an uprooted spruce root plate. A pine
stand and a
spruce stand in the direct
neighbourhood, both undisturbed, were chosen as references. The results show
the development
of the gamasid mite communities
from 2000 to 2003. A total of 54 species were found. The structure of the
predatory mite communities
changed substantially over the period investigated, especially at the destroyed
sites. In
the central site within the
windthrow area under study abundance and species number decreased
significantly.
Furthermore, the dominance
structures differed in the course of time as well as in comparison with the
undisturbed
sites. In the site in front of
the uprooted spruce root plate gamasid mites gradually colonized the highly
disturbed and
exposed soil substrate. The
results indicate that the windthrow event has caused a considerable disturbance
to the
predatory mite communities in
the affected sites, probably due to changed microclimatic conditions and to
changes
in food supply.
Key words: Gamasida,
windthrow, natural succession, soil ecology
Piotr
Skubala &
p. 123
The purpose of this study was
to contribute to our understanding of oribatid mites inhabiting fallen logs,
and to study
successional patterns in
Oribatida associated with deadwood. This research was carried out in the spruce
forest in the
downed spruce logs of similar
size. Forty soil and litter samples were additionally collected around logs. Overall
55,723
specimens of oribatid mites
belonging to 131 species were collected in 140 samples. Spruce deadwood is
settled by a
rich mite fauna. It becomes a
more rewarding food resource for mites as they tend to increase with log age,
although
the maximum density was
observed in log IV (i.e., the last but one decay class). It was both surprising
and interesting
to find that oribatid mite
fauna in deadwood is not depauperated in comparison with forest soil. For
oribatid mites
logs are a separate habitat
rather than simply an extension of the forest floor. Some mite species may
specialize on
deadwood, because 55 species
(of 131 in total) were obligate members of the intra-log community. The
structuring
forces that influence the
oribatid communities in their successional stages of decaying wood were
variable and
dependent on the stage of wood
decay. Against our expectations wood feeders did not prefer deadwood over soil
habitat, whereas eurytopic and
parthenogenetic species did not constitute a major part of the oribatid
community in
pioneer stages of wood decay.
Key words: Deadwood,
logs, oribatid mites, succession, forest
20 Effects of reforestation
with conifers on the communities of mesostigmatic mites in northern
María
Lourdes Moraza
Departamento de Zoología y
Ecología, Facultad de Ciencias, Universidad de Navarra, C/ Irunlarrea 1,
(Navarra), España. E-mail:
mlmoraza@unav.es
p. 129
The effect of reforestation of
Pinus nigra and Pinus halepensis in central and southern
Navarra (northern
mesostigmatic mite communities
inhabiting the soil was studied, and seasonal fluctuation of mite populations
over 1
year of sampling.
Reforestation causes a clear change in species richness of the community
(71-72% drop) and a significant
decrease of mite abundance
(31-50% loss). There are no significant differences in overall
(H) and evenness (J) when the
Mediterranean shrub (H = 2.92, J = 0.66) is replaced by a pine forest (H =
2.73, J = 0.72).
However, H and J significantly
increased when a pine forest (H = 3.34, J = 0.84) substitutes the natural oak
forest (H =
2.80, J = 0.63). Summer is the
critical, unfavorable season for Mesostigmata of this region in terms of their
abundance
and community diversity.
Key words: Mesostigmata,
reforestation, community analysis, species diversity, seasonal dynamics
David J.
Russell & Gerd Alberti1
1Zoological Institute &
Museum,
p. 135
The actenidid mite communities
were studied across a small-scale successional gradient in continental sandy
habitats
in southwest
Along the gradient, increasing
vegetation corresponded significantly with increasing soil eutrophication. Species-poor
communities with strong
eudominances of single species occurred in the open sands. Parallel to
increasing successional
status, actenidid densities
and species richness increased and dominances shifted strongly, with balanced
dominance
structures in the most
developed sites. Specialized, psammophilous species were mostly limited to the
open
sands and short-grass sites. Eurytopic
species were often limited to and dominant in the more highly eutrophied sites.
Many psammophilous taxa are
distributed world-wide but extremely disjunctly, occurring only in
nutrient-poor, abiotically
extreme psammic habitats.
Key words: Actinedida,
sandy habitats, psammophilous
Zoë
Lindo
Department of Biology,
University of Victoria, PO Box 3020, Victoria, British Columbia, V8W 3N5,
Canada. Present address:
Department of Biology,
E-mail: zoe.lindo@mcgill.ca
p. 143
Oribatid mite abundance,
species richness, and community composition in annual litter fall were compared
between
the high canopy of an ancient
temperate rainforest and the forest floor to evaluate whether litterfall,
including moss
debris, is a dispersal vector
for these organisms. Oribatid mites were extracted from litterfall collected
from canopy
(30 m) and ground (1 m) litter
traps associated with six western red cedar trees in the Walbran Valley on the
southwest
coast of
between canopy and ground
traps, as high amounts of litter were associated with both habitats. Litter
composition
differed between the two
habitats and cumulative input over larger spatial scales may prove to be
appreciably
different. Fifty-seven species
of oribatid mites were associated with total litterfall collected in canopy and
ground traps
over 12 months. Species
richness over the entire sampling period was similar between canopy and ground
habitats,
but oribatid mite species
composition differed significantly, and is most likely related to litter
composition and the initial
source of litter. Oribatid
mite abundance (number of individuals per gram dry weight) associated with
litterfall was
low compared to suspended soil
habitats, and not significantly different between litter accumulation in ground
and
canopy traps. Nevertheless, a
general trend of high litter input and high species richness associated with
litterfall in
canopy habitats, combined with
high disperser survivorship, suggests dispersal vectors such as moss mats are
important
for maintaining arboreal
oribatid mite communities.
Key words: Canopy,
oribatid mites, litterfall, dispersal vector
Shigenori
Karasawa* & Naoki Hijii
Laboratory of Forest
Protection,
p. 149
We reviewed the community
structure of oribatid mites associated with bird’s nest ferns in a subtropical
Japanese forest,
and seven trends became clear:
(1) most of the bird’s nest ferns on live trees occurred on host-tree species
that
typically grew in high density
and/or large basal area in the forest, and they preferred concave slopes; (2)
the amount
of accumulated litter in the
bird’s nest ferns was positively correlated only with fern size; (3) there was
a significant
difference between the
communities of oribatid mites between the litter and root components of bird’s
nest ferns;
(4) oribatid communities in
the bird’s nest ferns were relatively insensitive to the spatial distribution
of the fern in the
subtropical forest, however,
the density of oribatid mites in the litter decreased significantly with
increasing height of
the ferns above the ground;
(5) species diversity of oribatid communities in the ferns was significantly
lower than in
the bark of trunks or the
forest-floor litter and soil; (6) the oribatid faunas in the litter and roots
of the ferns were
more similar to those in both
the forest-floor litter and soil than to the faunas in the other arboreal
habitats; (7) presence
of bird’s nest ferns can
enhance species richness of oribatid mites in the arboreal environment, but
presence of
the ferns might not always
raise species richness of oribatid mites at the whole-forest scale, including
the forest-floor
habitats, because the species
composition of oribatid communities in the ferns was very similar to that in
the forestfloor
habitat.
Key words: Asplenium nidus complex,
bird’s nest ferns, Oribatida, species diversity, subtropical forest
24 Mites of the families
Anystidae and Teneriffiidae from
Mercedes
Guadalupe López-Campos & Ignacio Vázquez-Rojas
Facultad de Ciencias, UNAM,
Laboratorio de Acarología, México, DF 04510. E-mail: lupycony@yahoo.com,
mauro112003@yahoo.com.mx
p. 155
The mite fauna of the state
Baja California Sur is one of the least studied in
in 1998, focusing on
prostigmatic terrestrial mites, two families of the superfamily Anystoidea were
identified:
Anystidae and Teneriffiidae,
the later being a new record for
Erythracarinae resulted in the
diagnosis of two new genera, GN1 and GN2, both belonging to the family
Anystidae.
GN1 is monophyletic and
includes three species, GN2 is monotypic. Other genera and species found in
Sur include the anystids Erythracarus nasutus Otto, Tarsotomus sp., Paratarsotomus sp., Chaussieria capensis Meyer
et Ryke, and the teneriffiid Neoteneriffiola uta Tibbetts.
Key words: Prostigmata,
Anystidae,
25 Terrestrial species of the genus Nanorchestes (Endeostigmata:
Nanorchestidae) in
Matti
Uusitalo
Zoological Museum,
p. 161
Five species in the genus Nanorchestes Topsent & Trouessart have
been discovered from terrestrial habitats in
The reasons are provided for
naming them N. arboriger (Berlese),
N. cf. collinus Hirst, N. pulvinar Grandjean, N. cf.
antarcticus Strandtmann, and N. cf. llanoi Strandtmann. The species are
keyed and the old descriptions are complemented
by scanning electron
micrographs of their prodorsa.
Key words: Nanorchestidae,
Nanorchestes, taxonomy, soil environment,
26 Ptyctima (Acari, Oribatida)
in various habitats in
R.
Penttinen & V. Huhta1
Zoological Museum,
and Environmental Science,
p. 167
The oribatid species of the
taxon Ptyctima were studied in eight habitat types (four forests, three bogs,
and one
shore). Altogether 19 species
were found. The highest number of species (15) was found in marsh forests in
southern
and abundant species in
forests, and pine bogs. Phthiracarus longulus, P. boresetosus, and Steganacarus carinatus occurred in abundance in
coniferous forests, especially
in the southern and central parts of the country, whereas Rhysotritia ardua was found
there only occasionally. Hoploderma pavidus favoured bog habitats in
Key words: Bogs,
27 Distribution of Cosmochthonius
species (Oribatida: Cosmochthoniidae) in the eastern part of the Mediterranean,
R.
Penttinen &
Zoological Museum,
p. 171
Eleven species of the genus Cosmochthonius have been recorded in the
eastern
the former
semifoveolatus Subias, and C. asiaticus Gordeeva] have been found in
the western
the other six species (C. ugamaensis Gordeeva, C. zanini Niemi & Gordeeva, C. macrosetosus Ayyildiz & Luxton, C.
tenuisetosus Gordeeva, C. taurus Niemi, Gordeeva &
Ayyildiz, and C. ponticus Gordeeva) can be considered to
be
endemic. The most common
species in the eastern
Mediterranean islands (
coastal zone of Turkey, but it
regularly occurred in the southern and southeastern
of the species found in the
eastern region are documented here, and the habitus of eight species is
presented
in the form of SEM
micrographs.
Key words: Cosmochthonius,
oribatids, distribution,
28 An inventory of oribatid
mites, the main decomposers in bogs of Colchic Lowland (
Maka
Murvanidze & Eristo Kvavadze
p. 175
The bogs of Colchic Lowland
are of great international importance, because they are a foraging site on the
route for
many migrating and hibernating
birds. Productivity of the bogs is very high and they create a large mass of
dead organic
matter. We made an inventory
of the oribatid mites in three types of bogs: peat, cereal-Carex, and Juncus bogs. A
total of 47 species were
identified, one of which, Punctoribates manzanoensis (Hammer), is new to the fauna
of the
to other bog types. In peat
bogs the dominant species are Platynothrus peltifer, Nothrus pratensis,
Parachipteria punctata,
Punctoribates punctum, and Scheloribates laevigatus, in cereal-Carex bogs these are Zetomimus furcatus,
Nanhermannia nana, and P. manzanoensis, and in Juncus bogs: Steganacarus personatus,
Chamobates kieviensis,
and
Oppia nitens. The oribatid fauna also
includes species known from bogs of northern regions, such as Z. furcatus, O.
nitens, and Oppiella neerlandica. The density of oribatid
mites varies from 3,250 to 23,500 individuals/m2.
In some
sites mite density was high,
whereas species diversity was low. Such high numbers per oribatid species
indicate fast
decomposition. Decomposition
occurs in absence of many groups of other invertebrates and is mainly driven by
oribatid
mites.
Key words: Oribatida,
Colchic Lowland, decomposition, bogs, similarity index
29 The soil mites of
buttongrass moorland (
David
Green
School of Geography and
Environmental Studies, University of Tasmania, Private Bag 78, Hobart, Tasmania
7001, Australia.
E-mail: d.green@utas.edu.au
p. 179
The buttongrass blanket
moorlands are a unique habitat that constitutes a major landscape feature
within the
Tasmanian Wilderness World
Heritage Area (TWWHA) of southwestern
type that has had a long
history of regular burning by aborigines. Buttongrass may require a fire
frequency of
5-20 years in order to
maintain its suitability as habitat for many endemic vertebrates. The present
knowledge of the
Acari in the peat/litter
accumulations in buttongrass is very poor and their response to fire is not
understood. This
study addresses the following
questions: (1) How do soil mite communities in recently burned buttongrass
compare
with those that have not been
burned in several decades? and (2) Are fire frequencies of between 5-20 years
sufficient
for soil mite populations to
recover? A survey of soil mites was undertaken in a chronosequence of age
classes
of buttongrass at two study
areas in the TWWHA. Six soil-cores were removed from up to four sites of each
age class
at 3-months intervals for 1
year, a total of 870 soil cores. All mature mites were identified to
morphospecies with many
individuals identified to
genus or species. The soil mite community within buttongrass was found to be
rich both at
family and species level, in
Oribatida, Prostigmata, and Mesostigmata. This community was significantly
affected by
fire, with a reduced number of
species for many years post-fire. Density and diversity of these populations
are positively
correlated with age and many
communities only changed significantly after 30-40 years post fire, which is in
conflict
with the prevailing management
practice of burning every 5-20 years.
Key words: Soil
mites, moorland, peat, fire, management
30 The water mite genus Torrenticola (Hydrachnidia: Torrenticolidae) in
Tom Goldschmidt
Zoologische Staatssammlung München, Münchhausenstraße
21, D-81247 München, Germany.
E-mail: tomgoldschmidt@web.de
p. 185
The genus Torrenticola is found in springs and
running waters on all continents except
diversity in the Tropics and
Northern Temperate regions. In Costa Rican streams and springs it is the most
frequent
and abundant water mite genus
In a recent study 36 new species were described, raising the number of species
known from
analysed. Based on these data,
the first ecological analyses on Neotropical water mites are presented. Torrenticola
spp. were found in all types
of springs and running waters all over
demands and distribution
patterns are apparent. Analyses of habitat preferences of the species revealed
linkages of
particular species to certain
habitat types (springs, large rivers, etc.), different sensitivity of the
species towards pollution,
and a distinct altitudinal
zonation. These results demonstrate the great potential of this group of mites
in the
monitoring of aquatic
habitats. The finding of up to seven species of the genus at a single locality
allows the study of
microhabitat specificity and
niche-differentiation, as well as general patterns of species assemblages. High
mountain
regions could be determined as
main centres of diversity and endemism. Furthermore, idiosoma size was found to
differ
among species and between
sexes, and to vary with habitat and elevation. Finally, the state of knowledge
on the
diversity and general
distribution patterns of the genus in the
Key words: Torrenticola, Hydrachnidia,
spring, running water
31 Stage distributions of
cunaxids in soil and litter at Chamela,
Blanca
E. Mejía-Recamier & Gabriela Castaño-Meneses
Ecología y Sistemática de Microartrópodos, Depto. Ecología y Recursos Naturales,
Facultad de Ciencias, UNAM, 04510
México, DF. E-mail:
tellarecamier@yahoo.com.mx
p. 193
Cunaxid mites are considered
to be important predators in soil communities, but little is known of the
distribution
over their development stages.
We studied the stage distribution of edaphic cunaxid mites in a deciduous dry
forest
in the Pacific region of
at the Chamela Biological
Station (19°30’N, 105°03’W, 150 m asl),
were collected from 43
species, including adults and immature forms. The proportion of adults was 74%
(females 53%,
males 21%), 10% tritonymphs,
1% deutonymphs, 6% protonymphs, and 9% larvae. Immature stages were more
abundant
in the soil than in the
litter. Seasonal dynamics was recorded for the various stages. These data are
the first on
the seasonal distribution of
developmental stages in edaphic cunaxid mites.
Key words: Cunaxidae,
ontogenetic development, seasonal dynamics, soil, litter
32 Mites (Mesostigmata)
inhabiting bird nests in
Peter
Fend’a
Department of Zoology, Faculty
of Natural Sciences,
E-mail: fenda@fns.uniba.sk
p. 199
In
2,500 nests of birds from 110
bird taxa. Most (97%) of the mite specimens were parasitic, representing 26
species, of
which only six were typical
avian parasites. All blood parasites had a wide host range, yet were specific
for nest type
(except for Dermanyssus chelidonis and Eulaelaps novus). Their abundance peaked in
the nesting period. The 3% of
the mite specimens that were
non-parasitic were the most speciose (203 species). The composition of the
non-parasitic
mite fauna in the nests was
dependent on nest location (habitat) and nest environment (biotope).
Key words: Mesostigmata,
Aves, nest fauna, ectoparasites,
33 Ereynetid mites (Tydeoidea:
Ereynetidae) associated with garlic crops in
Ignacio
Mauro Vázquez-Rojas1 & Edith G. Estrada-Venegas2
1Facultad de Ciencias, UNAM,
Laboratorio de Acarología, México, DF 04510. E-mail: mauro112003@yahoo.com.mx;
and
2Colegio de Postgraduados,
Texcoco, México
p. 207
the main garlic producer, with
50-70% of the total garlic export. Recent data show that there are 19 genera
and 169
named species in the Ereynetidae,
more than half the number of species are in the Speleognathinae, all of them
are
parasites. In total 51 species
of free-living ereynetids belong to the genus Ereynetes. Until now Ereynetes
(Opsereynetes) simplexus, E. (O.) robustus, E. (Anereynetes) tuberculatus, E. (A.) sabinensis, E. (Ereynetes) amplectorus,
E. (E.) faini, and Riccardoella oudemansi have been described and/or
recorded from
spp., two Neoboydaia spp., and one Trispeleognathus species associated with birds
are also cited. In this study we collected
soil samples inside garlic
crops in several localities of two municipalities in the state of Guanajuato
from 2002
to 2005. Two species of
Ereynetidae are recorded for the first time for garlic crops, Ereynetes (E.) amplectorus and E.
(E.) faini with 179 and 81 specimens
respectively; a total of 260 specimens were studied. Data on the presence of
females, ovigerous females,
males, and juveniles collected in the course of the garlic crop season are
included.
Females were more numerous
than males in both species. The egg structure is described.
Key words: Ereynetidae,
garlic,
Physiological
Acarology
34 Nutritional biology of
oribatid mites from different microhabitats in the forest
Jaroslav
Smrzv
Department of Zoology,
p. 213
Two or three microhabitats
were defined within each of several habitats within a forest. For example, if
‘tree’ is a habitat,
its microhabitats are the moss
cover on the tree, the moss at the foot of the tree in contact with the soil,
and the
soil around the tree. The
microhabitat community structure of oribatid mites was recorded. The
nutritional biology,
especially the type of food
and the digestion pattern, of the more dominant species was monitored. Mites
were
extracted in Berlese-Tullgren
funnels, collected in modified Bouin-Dubosque-Brasil fixation fluid, sectioned
in paraplast,
and stained with Masson
triple. Faecal pellets in the rectum were also stained with acridine orange and
observed under fluorescent
light. Mite microanatomy was evaluated based on nutritional parameters (food
bolus,
food type, activity of the
walls of the intestine, faecal pellets, bacteria within the body, nutritive
deposits, metabolites).
Some species consume and
digest a specific type of food in all microhabitats of one habitat. But others
are able
to shift diet according to
current food supply in a particular microhabitat. A third type of species is
ubiquitous and usually
consumes a mixture of
unspecified food types in every microhabitat studied. Obligate mycophagous
oribatids
(e.g., Damaeus, Belba or Metabelba) seem to be highly
specialized. These genera inhabit mostly soil or microhabitats
in contact with soil (e.g.,
mosses on soil), and are rarely found in moss cover on trees, away from the
soil. Other
species inhabiting soil
microhabitats as well as moss covers on trees (Achipteria coleoptrata, Hermannia gibba) can
adapt to the nearly pure
fungal food in soil microhabitats, although they graze on a different type of
food in a microhabitat
consisting of moss covering a
tree.
Key words: Microhabitats,
moss, community structure, microanatomy, nutritional biology, Oribatida
35 Enzyme activities and
internal bacteria of saprophagous soil mites (Acari: Oribatida, Acaridida)
Jaroslav
Smrzv
Department of Zoology,
p. 217
Several saprophagous mites
(Acari: Oribatida, Acaridida) were tested for chitinolytic activity of their
enzymes. These
mites were sampled in the
field (Damaeus,
Belba, Metabelba) or obtained from cultures (Archegozetes, Scheloribates,
Tyrophagus). Mites were tested on
several fungi from a fungal collection (Alternaria, Fusarium), as well as fungi isolated
from mite-rearing boxes (Penicillium, Mucor). These tests involved (1)
light and fluorescence microscopy of adequately
stained mites to detect internal,
but extra-intestinal, bacteria, (2) staining of mite homogenates to detect
chitinase
activity, and (3) plating of
mite homogenates and purification to obtain pure cultures of the internal
bacteria for
identification. Mycophagy of
the mites was classified into three types: (1) grazing and digesting fragments
of fungi,
including their chitinous cell
wall, as proven by chitinase activity, (2) cutting and ingesting hyphae, but
digesting only
the cell content (no chitinase
activity), and (3) piercing mycelium and sucking its content (chitinolytic
bacteria were
plated from the homogenate of
those mites, but no chitinase activity).
Key words: Mycophagy,
microanatomy, chitinolytic activity, chitinolytic bacteria, Oribatida,
Acaridida
Mari
Horigane & DeMar
E-mail:
taylor@sakura.cc.tsukuba.ac.jp
p. 221
Vitellogenin (Vg) synthesis
and oocyte development appear to be induced by ecdysteroids in the soft tick Ornithodoros
moubata. Vg transcription in insects
has been shown to be mediated by two nuclear receptors, an ecdysteroid receptor
(EcR) and a retinoid X
receptor (RXR). EcR and RXR expression in female ticks increase after
engorgement.
However, there is little
information about EcR and RXR expression in tissues as related to reproduction.
Therefore, the
sites of EcR and RXR
expression during vitellogenesis were determined. Expression levels of EcR and
RXR were determined
for salivary glands, midgut,
ovary, anterior reproductive tract, fat body, muscle, and cuticle of mated
females
by reverse transcriptase
RT-PCR and real-time PCR. Ovaries showed constant expression of EcR and RXR
throughout
the adult female stage. The
fat body showed higher expression of EcR and RXR on one day after engorgement. The
fat
body of female ticks has been
reported to be the organ of Vg synthesis. Therefore, increases in EcR and RXR
of the fat
body support the hypotheses
that the site of Vg synthesis is the fat body and ecdysteroids regulate this
synthesis in
O. moubata. EcR and RXR in the ovary and
anterior reproductive tract may also play roles in the regulation of oocyte
development.
Key words: Ornithodoros moubata, soft tick, ecdysteroid, ecdysteroid receptor (EcR), retinoid X receptor
(RXR), vitellogenesis
Jinlin
Zhou1,2 & Kozo Fujisaki1
1National
Obihiro,
p. 227
Proteins capable of selective
and specific inhibition of cysteine protease have been identified as cystatins
and are isolated
from a variety of microbes and
tissues of animals and plants. The physiological function of these proteins
have
been proposed in regulation of
protein turnover and defending against pathogens, as well as in modulating the
host’s
immune response. Genes
encoding cystatins have been found in several kinds of ticks, but the function
of cystatin in
ticks is not understood. We
cloned a gene encoding cystatin from the hard tick Haemaphysalis longicornis, and designated
it Hlcyst-2 (H. longicornis cystatin-2). The full-length cDNA is 569
bp, encoding a putative 133 amino acids protein
with an obvious signal
peptide. The cystatin was expressed most in tick midgut and hemocyte. Blood
feeding
induced a significantly
increasing expression in midgut. Real-time PCR confirmed that adult ticks
injected with the
immuno stimulant
lipopolysaccharide (LPS), expressed Hlcyst-2 1.6× more than control ticks
injected with phosphatebuffered
saline. Babesia gibsoni-infected tick larvae expressed
Hlcyst-2 1.8× more than uninfected larvae. The recombinant
protein also showed a
significant growth-inhibitory effect on B. bovis cultured in vitro. These results indicated
this cystatin Hlcyst-2 is
involved in tick innate immunity.
Key words: Haemaphysalis longicornis, cystatin, Babesia gibsoni, innate immunity
Chemical Acarology
38 Oil gland secretions in
Oribatida (Acari)
Günther
Raspotnig
Karl-Franzens-University,
E-mail:
guenther.raspotnig@uni-graz.at
p. 235
The chemical ecology of
Oribatida is tightly integrated with a distinct exocrine system in the
opisthosoma, known as
‘oil glands’ (syn.
opisthonotal glands). Representing homologous structures, oil glands characterize
the four more
derived cohorts of Oribatida
(Parhyposomata, Mixonomata, Desmonomata, and Brachypylida), but also the
Astigmata, as the monophyletic
unit of ‘glandulate Oribatida’. Generally, oil glands constitute large
intima-lined sacs
that are located in the
dorso-lateral regions of the idiosoma and that open to the body outside via a
single (frequently
flapped) pore on either side
of the notogaster. Secretions of more than 20 oribatids have so far been
analyzed. They
consist of hydrocarbons,
terpenes, aromatics, and alkaloids. Many components occur in specific
combinations; secretion
profiles characterize groups
(on any taxonomic level) and have emerged as tools for phylogenetic analyses:
Parhyposomata, e.g., produce
phenolic- and naphthol-rich secretions, whereas a distinct set of terpenes and
aromatics
(the so-called ‘astigmatic
compounds’) is considered synapomorphic for middle-derived Mixonomata and all
groups above (‘astigmatic
compounds-bearing Oribatida’). In some subgroups of the ‘astigmatic compounds-bearing
Oribatida’, these components
are not easily traced as they tend to be reduced and replaced by others. Functionally,
oil glands produce various
allomones against predators and fungi, and alarm pheromones for intraspecific
communication.
Pheromonal properties of oil
gland compounds probably evolved early in ancient oil gland-bearing oribatids
from purely defensive
functions, culminating in a radiation of semiochemical roles (alarm,
aggregation, sex) in oil
glands of the Astigmata.
Key words: Oil
glands, opisthonotal glands, Oribatida, semiochemicals, Astigmata
Yasumasa
Kuwahara
Faculty of Bioenvironmental
Science,
E-mail:
kuwahara@kyotogakuen.ac.jp
p. 241
Astigmatic mites are known to
achieve intraspecific communication on alarm, sex, and aggregation by
pheromones
released from one pair of
opisthonotal glands. So far, species have been found to use a single active
compound, or different
compounds, to achieve two of
the three communication functions. Each communication function emerges
from the conditions the mites
are facing, from functional characteristics such as dose-response relationships
and
active dose-range, and from
the relative abundance of the active compounds in the gland. Here, findings on
combinations
of two communication functions
from products of opisthonotal glands are summarized for species of
Astigmata and new evidence is
presented for a species, Rhizoglyphus setosus, that is capable of achieving all three
communication functions –
alarm, sex, and aggregation – from products of opisthonotal glands. The
possible mechanisms
that lead to multiple
communication functions from products of one paired gland are discussed.
Key words: Astigmata,
Rhizoglyphus
setosus, communication, sex
pheromone, alarm, aggregation
F.C.C.
Hountondji1,2,3, M.W. Sabelis2 & R. Hanna1
1International Institute of
Tropical Agriculture, 08 BP 0932,
Ecosystem Dynamics, Population
Biology Section, University of
and 3Expertise, Action and Research
for Development (EAR-Development),
E-mail: fabienho@yahoo.com
p. 249
The role of infochemicals in
mediating interactions between herbivores and their foraging natural enemies,
mainly
predators and parasitoids, is
well established, but very little is known about infochemical use in
interactions between
herbivores and their
sit-and-wait pathogens. This paper reviews the role of infochemicals in
interactions between the
cassava green mite (CGM), Mononychellus tanajoa, and its fungal pathogen, Neozygites tanajoae. In a closed-dish test,
herbivore-induced plant
volatiles (HIPV) from cassava were found to influence conidia and capilliconida
production of
the fungus but the effect of
HIPV varied between isolates. HIPV consistently promoted conidia production of
one isolate
and capilliconidia production
of another. Olfactory trials with one of the HIPV, methyl salicylate (
conidia production of the same
isolate, but no effect was found on capilliconidia production. In contrast to
the
effect of HIPV, green leaf
volatiles inhibited spore production, suggesting that the fungus uses HIPV to
signal the presence
of hosts. The behaviour of the
mite towards infective spores was investigated in a two-choice unit (discs with
vs.
without spores) and on
detached leaves. Mites avoided the discs with spores, in particular for one
isolate. Similar
observations were made on
detached leaves where more mites were found on leaf lobes without spores than
on
those with spores. However,
mites did not avoid mummified infected mites that did not yet produce spores,
suggesting
that the fungus may profit
from going unnoticed inside the live infected mite to reach densely infested
patches.
Key words: Acaropathogen, avoidance,
green leaf volatiles, herbivore-induced plant volatiles, methyl salycilate,
Mononychellus tanajoa
41
Herbivore-induced plant volatiles prime two indirect defences in lima bean
Yasuyuki Choh & Junji Takabayashi
Center for
Ecological Research,
E-mail:
junji@ecology.kyoto-u.ac.jp
p. 255
Herbivore-induced
plant volatiles (HIPV) are emitted by plants in response to herbivory and
attract natural enemies
of herbivores,
thereby inducing an important indirect defence against herbivores. Evidence
supports the hypothesis
that plants become
more defensive against herbivores after exposure to HIPV and that this is a
type of priming, or
preparation by the
plant perceiving an HIPV signal to respond to herbivory. We report the priming
of two induced indirect
defences:
HIPV-mediated induction of predator attraction and the secretion of extrafloral
nectar (EFN), known as
an alternative
food source for natural enemies of herbivores. When uninfested lima bean plants
(Phaseolus
lunatus)
were exposed to
HIPV, the plants attracted more predatory mites (Phytoseiulus
persimilis) and secreted larger
amounts of EFN
than unexposed plants. Further, when HIPV-exposed plants were infested by
spider mites
(Tetranychus
urticae) for 2
days, the plants attracted more predators and secreted larger amounts of EFN
than plants
that were infested
for 2 days after exposure to uninfested plant volatiles. However, there
were no differences in the
attraction and the
EFN secretion when they were infested for 4 days. Predatory mites survived
longer when supplied
with EFN and
stayed longer on uninfested plants that had been supplemented with additional
extrafloral nectar. From
these results, we
conclude that the priming of HIPV-exposed plants recruits predators and induces
the secretion of
EFN that functions
to protect the plants before and after herbivory.
Key words: Extrafloral
nectar, herbivore-induced plant volatiles, indirect defence, induced response, Phytoseiulus
persimilis,
plant-plant
interactions, priming, Tetranychus urticae
Taro
Maeda
Insect Interaction Research
Unit, National Institute of Agrobiological Sciences, Ohwashi 1-2, Tsukuba,
p. 259
I investigated the
relationship between olfactory response, patch-leaving tendency, predation
rate, fecundity, and
developmental time of 11
geographical populations and 13 isofemale strains of the predatory mite Neoseiulus womersleyi.
Significant differences were
found in all these traits and behaviors among the geographical populations and
among the isofemale strains. A
significant positive correlation was found only between the olfactory response
and the
patch-leaving tendency of
geographical populations. There was no such relationship among the isofemale
strains.
These results suggest that the
positive correlation between the behavioral traits among geographical
populations was
not caused by genetic factors.
The difference in the behavioral traits and the correlation among geographical
populations
is discussed from an
ecological point of view where foraging strategy is determined by both the
olfactory
response and the patch-leaving
tendency.
Key words: dispersal tendency, genetic
correlation, herbivore-induced plant volatiles, life-history traits, olfactory
response, Tetranychus urticae
Evolutionary and Ecological Acarology: Intraspecific
Variation
Louise
Coetzee
Acarology Department,
E-mail:
louise.coetzee@nasmus.co.za
p. 267
Population differences of Afroleius simplex Mahunka have been studied by
means of multivariate morphometric
analyses based on nine
variables measured from 87 specimens. Principal component (PCA), discriminant
function, and
cluster analyses were
performed. There is no separation of specimens into clusters and therefore the
specimens are
regarded as a single species.
Key words: Afroleius simplex, principal component
analysis, discriminant function analysis, cluster analysis
S.
Guichou, M.-S. Tixier &
Montpellier SupAgro / UMR CBGP
2 Place Pierre Viala, 34060
p. 271
Neoseiulus californicus is distributed worldwide and
well-known for its predatory effectiveness on mite pests, especially
Tetranychus species. The objective of this
study was to (1) assess the range of variation of morphological and
morphometrical characters
defining the species, and (2) find diagnostic tools to discriminate between
strains. Thirty
females of each of 10 strains
were mounted on slides and 42 characters were analysed. There are significant
differences
among strains for 31
characters; the range of (intra-strain) variation for each parameter is low. The
discriminant
analysis indicated that all
factors measured allowed the discrimination of the strains with less than 6%
error, except
for the Greek strain.
Molecular experiments indicated very low variability for all five markers
tested (two nuclear and
three mitochondrial fragments).
For the 18S fragment, no nucleotide divergence was observed between three
populations.
For the ITS-5.8S, the
variation was 0-0.6% between two strains. For the 12S fragment, nucleotide
divergence
was observed between the 10
strains (0-0.4%). For mitochondrial markers, the variation rate was also
surprisingly low:
0.3% between two strains for
one fragment, 0-2.5% between five strains for the other. The highest diversity
was
observed between the
analysis. However, the Spanish
strain that could be separated based on morphological markers appeared to be
molecularly similar to the
other strains tested. Worldwide dispersion of N. californicus and mixing may explain the low
molecular variability. Up to
now, morphological markers would be more helpful for discriminating between N. californicus
strains than molecular ones.
However, other molecular markers will be tested.
Key words: Phytoseiidae, Neoseiulus californicus, taxonomy, morphology,
mt-DNA, nuclear DNA
A.
Walzer, M. Castagnoli1, S. Simoni1, M. Liguori1,
Resources & Applied Life
Sciences, Peter Jordanstrasse 82, A-1190
1Istituto Sperimentale per la
Zoologia Agraria, via di Lanciola 12/A,
Agricultural Research
Organization, Ministry of Agriculture,
p. 279
Biological control of spider
mites (Acari: Tetranychidae) under dry conditions is a serious problem, which
cannot be
solved with the currently
available strains of predatory mites (Acari: Phytoseiidae). However, there is
considerable
intraspecific variability in
the degree of adaptation to low humidity, allowing the screening for a
drought-resistant
strain. Due to its plasticity
in biological and ecological traits Neoseiulus californicus qualified as a suitable
species for
strain screening. Egg
hatchability, juvenile survival and oviposition rate of eight N. californicus strains were evaluated
at three or four humidity
levels (ranging from 64.0 to 75.6% r.h. at 25 °C). Strains came from
Hérault/France (FR),
Tuscany/Italy (FL),
Valencia/Spain (SP), La Cruz/Chile (CH), Sicily/Italy (SI), and California/USA
(C-BOKU, C-ISZA, CARO).
Pronounced intraspecific
variation of the traits evaluated at 64.0% r.h. served as a basis to rank the
strains and
to determine three distinct
groups. In the first group (SP, FL, C-ISZA) egg and juvenile survival
probability was nearly
zero. The second group (FR,
CH, C-ARO) was characterized by low egg survival probability (0.14-0.18), but
high survival
probability of mobile
juveniles (0.69-0.82). Strains of the third group had the highest egg and juvenile
survival probabilities
among the strains evaluated:
0.37 and 0.83 (SI), and 0.38 and 0.96 (C-BOKU), respectively. We conclude that
the strains of the latter
group are the most promising ones with respect to spider mite control under
relatively dry
conditions.
Key words: Biological control, humidity,
intraspecific variation, life-history traits, Neoseiulus californicus, spider mites
Evolutionary and Ecological Acarology: Reproductive
Behaviour and Sociality
46 Spider mites as study
objects for evolutionary biology
Yutaka
Saito
Laboratory of Animal Ecology,
Research Faculty of Agriculture,
E-mail:
yutsat@res.agr.hokudai.ac.jp
p. 287
I consider spider mites, and
other mite groups, to be excellent material for evolutionary ecology and
genetic studies,
because of their low mobility,
rapid development, ease of rearing, diverse genetic systems, and variable
ecology. Using
spider mites, we have revealed
various topics in evolutionary ecology: (1) spider mites have variable
(communal social
and sub-social) life types,
thus variable ecologies on plant leaves; (2) cooperation and aggressiveness
vary among spider
mite species, making them
promising material for the study of natural selection operating on behaviour;
(3)
despite their haplo-diploid
genetic system, spider mites have retained female-limited recessive genes that
cause
inbreeding depression; (4)
life-type diversity of spider mites has evolved partly through interactions
with predators;
and (5) speciation is thought
to have occurred through a shift in host plants and the accompanying
differences in predation
pressure. Here, I review my 30
years of work to show the useful and unique aspects of spider mites and to
point
out problems that had – and
still need – to be solved in order to learn how spider mites can become useful
as an object
for evolutionary study
Key words: Diversity, evolutionary
ecology, sociobiology, bamboo mites, life types, Stigmaeopsis
Piotr Lukasik,
Mal/gorzata Zygadl/o & Jacek Radwan
E-mail: radwan@eko.uj.edu.pl
p. 295
Previous work on the acarid
mite Rhizoglyphus robini has shown that the male’s success in sperm competition is significantly
affected by the
electrophoretic form of the enzyme phosphogluconate dehydrogenase (Pgdh): males
homozygous for the slow (S)
form were superior to males homozygous for the fast (F) form. However, in that
study
the paternity was measured
when progeny reached adulthood, therefore sperm competitiveness might have been
confounded with the effect of Pgdh on survival. Here, we avoided
this problem by using a sterile-male technique to
assess the effect of Pgdh genotype on the success of
males in sperm competition. We also estimated the competitive
ability of heterozygotes for
the first time. We found that S-homozygous males sired a significantly higher
proportion
of offspring than F-homozygous
males while competing against irradiated males from the background population,
whereas sperm competitive
ability of SF heterozygotes was intermediate between that of the two
homozygotes.
Key words: Phosphogluconate
dehydrogenase, Rhizoglyphus robini, sperm competition, enzyme polymorphism
H.C.
Proctor, G. Williams & D.H. Clayton1
Department of Biological
Sciences,
E-mail: hproctor@ualberta.ca;
and 1Biology Department,
p. 299
Male polymorphism, in which
two or more male morphologies occur within a species, is a widespread
phenomenon
in the Astigmata. Factors
determining which morph a male will become have been studied for several
free-living
species. In Sancassania berlesei (Michael) (Acaridae), male
nymphs develop into relatively unmodified homeomorphs
at high population densities,
and into highly modified, aggressive heteromorphs at low densities. We tested
whether
population density correlated
with male morph ratio in the dimorphic feather mite Falculifer rostratus (Buchholz)
(Falculiferidae). Twenty-one
pigeons (Columba livia Gmelin)
from
extracted were identified to
stage, sex, and male morph. Excluding four birds that had no F. rostratus, total densities
per host ranged from 1-1155.
Numbers of heteromorph males correlated positively with population density, but
homeomorph numbers had no
obvious relationship with density. Ratios of homeomorph:heteromorph were
frequently
higher at low population
densities than at high densities – the opposite of the pattern observed for S. berlesei.
An alternative hypothesis that
quality of diet may determine morph ratio is tested and receives little
support. It is
possible that male morph is
determined by density in F. rostratus, but that it is controlled at a finer physical scale
(e.g.,
per feather) than could be
measured in this study. Other possibilities are that morphs are determined
genetically or
by host variables we did not
account for (e.g., moulting status).
Key words: Pigeon, heteromorph,
homeomorph, Astigmata, population size
Peter
Martin
Christian-Albrechts-Universität
zu Kiel, Zoological Institute, Olshausenstr. 40, D-24098
E-mail:
pmartin@zoologie.uni-kiel.de
p. 303
Details of reproduction,
development, and sexual behaviour are known only for a few water mite species,
mostly from
standing water. This study
reports laboratory observations on 20 species from two small streams in
Ovigerous females carried
between 1.4 (Aturus fontinalis)
to 69 eggs (Sperchon setiger).
In most species, eggs were
laid consecutively in distinct
clutches, generally with <50 eggs per clutch. Separately deposited single
eggs were exclusively
found in containers housing
the small species Feltria rouxi,
Ljania
bipapillata,
and A. fontinalis.
Lifetime reproduction
was recorded for Sperchonopsis verrucosa (110 eggs in 3 years) and Sperchon thienemanni (122 eggs in 2
years). Development from egg
until larval hatching took 2-10 weeks, eggs laid late in the year took up to 3
months.
The deutonymphal stage
generally takes several months, depending on food supply. The period between
the immobile
deutonymph and adult emergence
takes 1-4 weeks. In the laboratory, life spans vary from several months (male
F. rouxi, A. fontinalis) up to 3 years (female S. verrucosa, Lebertia glabra). In most cases, spermatophore
deposition
occurs even in the physical
absence of females. For stream-living species in temperate climates, different
patterns of
overwintering are known:
hibernation often occurs as adult. Overwintering exclusively as deutonymph has
never been
observed, but part of the
population often hibernates at this stage. In species with parasitic larvae
late in the year
(Wettina podagrica, L. glabra and Sperchon squamosus), most specimens probably
hibernate at the deutonymphal
stage. Overwintering as a
well-developed larva remaining within the clutch envelope has been observed
only in
Atractides nodipalpis. Hibernation at the egg stage
is known from the literature for Sperchon glandulosus.
Key words: Rheobiontic water mites, behaviour,
development, life cycle strategies, overwintering
50 Nest microflora in the social spider mite, Stigmaeopsis longus (Acari:
Tetranychidae)
Ayumi
Kikuchi & Michiko Tanaka1
Lab. Animal Ecology,
E-mail:
kikuayumm21@yahoo.co.jp; and 1Lab. Applied
Microbiology, Microbial Resources and Ecology, Graduate school of
Agriculture,
p. 313
Group-living has many
benefits, but it also has some costs. The social spider mite Stigmaeopsis longus weaves nests
on the undersurface of dwarf
bamboo leaves and deposits fecal piles at specific sites for nest sanitation. These
nests
are hypothesized to have a
protective function against predators. However, predators are not the only natural
enemies,
pathogens are also important. If
the nest has a protective effect against microbes, and if waste management
plays a role in nest
sanitation, it is expected that the number and diversity of phylloplane fungi
inside the nest should
differ from the outside. As
such, we attempted to compare the fungi inside and outside nests. Our results
show that
fungal populations inside
differed significantly from those outside the nests, and Cladosporium cladosporioides was
the dominant species both
inside and outside, but it was more abundant inside. Furthermore, there was a
significant
difference in the correlation
of C. cladosporioides with other fungi inside vs. outside nests. We conclude that C. cladosporioides
may have a suppressing effect
on other, more harmful, fungi in S. longus nests.
Key words: Stigmaeopsis longus, phylloplane fungi, Cladosporium cladosporioides, nest sanitation
Evolutionary and Ecological Acarology: Demography,
Diapause and Dispersal
51 Seasonal adaptations in the
life cycles of mites and ticks: comparative and evolutionary aspects
Valentin
N. Belozerov
Department of Entomology,
Biological Research Institute,
198504,
p. 319
Data on seasonal adaptations
(in particular on distribution of dormant stages) within the life cycles of the
Acari
(Chelicerata, Arachnida) are
reviewed and compared with similar traits in mandibulate arthropods (insects
and crustaceans).
They all share responses to
photoperiod and temperature, but there are some similarities and essential
peculiarities
with regard to the ontogenetic
distribution of diapausing stages for each of these groups. The main similarity
concerns the species-specifity
of the dormant stage position, whereas differences concern the number and
ontogenetic
distribution of these stages
within life cycles. Plesiotypic traits of seasonality in the Acari are
expressed in the presence
of complex ‘systems of
seasonal control’ (SSC) with various dormant stages enabling the control of
perennial,
semivoltine, and monovoltine
development, whereas apotypic traits are characterized by simple SSC with a
limited
number of dormant stages for
control of mono- and polyvoltine development. The Oribatida, a major part of
the
Prostigmata, and all Ixodida
show evolutionary transformations from plesiotypic to apotypic traits of
seasonality, but
Astigmata, some Prostigmata,
and Mesostigmata show fixed apotypic traits only, which pleads for their
derived state.
Primary adaptations enabling
seasonal control of development in arthropods emerged most likely at the
earliest steps
of the origin of life on
earth, and evolved thereafter from the ancestral devices within various taxa of
animals according
to their organization, manner
of life, geographic distribution, and environmental heterogeneity. The
evolution of
seasonal adaptations in the
Acari occurred through transformation of ancestral systems of seasonal control
with
numerous dormant stages into
systems with a reduced number of dormant stages, or even a single dormant
stage.
Key words: Dormant stages, ontogenetic
distribution, diapause, seasonal adaptations, Acari, insects, crustaceans
52 Embryonic diapause and cold hardiness of Ixodes ricinus eggs (Acari: Ixodidae)
Hans
Dautel* & Wilhelm Knülle
Institute of Applied
Zoology/Animal Ecology, Freie Universität
*Present adress: IS Insect
Services GmbH, Haderslebener Str. 9, 12163
p. 327
Ixodes ricinus is medically the most
important tick species in temperate
assess the effect of
photoperiod and low-temperature exposure on termination of embryonic diapause
and on cold
hardiness in
shortday (L14:D10), or at an
outdoor site providing natural temperatures and daylength. Eggs of defined ages
were
continuously kept under these
conditions or subjected to changes in photoperiod and temperature, and the
effect on
diapause incidence was
observed. At 15 °C, non-diapause and diapause eggs hatched after 70-120 and
140-240 days,
respectively. Interestingly,
most egg masses did not show an all or nothing reaction but a certain
percentage of diapause
eggs. Cold exposure of eggs to
4 °C for 6 weeks completely terminated diapause, whereas the effect of
photoperiod
was negligible. Also exposure
to temperatures between -10 and -20 °C for 24 h terminated diapause. At the
outdoor site, eggs were laid
in winter, from mid October to early April. All eggs hatched between mid June
and early
July. The supercooling point
of these eggs was around -28 °C between November and January and rose to -27 °C
in
April. At constant 15 °C, the
supercooling point rose from -30 °C in young eggs to -24 °C in physiologically
older eggs.
The lower lethal temperature
in diapause and non-diapause eggs was -21.6 and -18.0 °C, respectively, but the
difference
was not significant.
Key words: Ixodes ricinus, diapause, cold hardiness,
egg
A.M.
Camerik
School of Animal, Plant and
Environmental Sciences, University of the Witwatersrand, Wits, 2050,
p. 333
Based on Farish & Axtell’s
(1971) definition of phoresy and using Euzet & Combes (1980) terminology
for the classification
of host-parasite
relationships, Athias-Binche (1994) proposed a classification of eco-physiological
phoretic
behaviour in mites. However,
in the light of recent publications on mite-host relationships and of my own
observations,
Farish & Axtell’s (1971)
definition of phoresy has to be revised and, consequently, Athias-Binche’s
(1994) classification
adapted.
Key words: Phoresy, mite-host
relationships, ecological and eco-physiological categories, evolution
54 Pediculaster–host relationships (Acari:
Siteroptidae)
A.M.
Camerik
School of Animal, Plant and
Environmental Sciences, University of the Witwatersrand, Wits, 2050,
p. 337
Pediculaster species are mites that are
associated mainly with Diptera. They occupy very specific attachment sites on
their host and have a
specialised morph for dispersal. This suggests a long-standing relationship
with their hosts.
Based on a modified version of
Athias-Binche’s (1994) eco-physiological phoretic categories, the Pediculaster species
of this study are obligate
phoretics in their natural habitat. Using a statistically determined host
preference index, I
propose to put P. morelliae, P. gautengensis, and P. gracilis into the eco-ethological
category, and P. norrbomialis into
the stenoxenous category.
Key words: Pediculaster, phoresy, host-preference
index, quantifying eco-physiological categories
Jérôme Niogret1,2, Jean-Pierre Lumaret1 & Michel Bertrand1
1UMR
5175 CEFE, Ecologie des Arthropodes, Laboratoire de Zoogéographie, Université
Montpellier 3, route de Mende, F-
34199
p. 343
Macrochelid mites have
phoretic associations with coprophilous arthropods, thereby promoting dispersal
and colonization
of new substrates. Contrasting
strategies were observed. Opportunistic mites like Macrocheles perglaber
exploit a large range of
carriers, whereas specialists like M. saceri occur only on roller dung beetles (genus
Scarabaeus). The opportunistic species
live inside dung pats, whereas specialists live in the pedotrophic nests of
Scarabaeus beetles. These modes of life
are expected to have consequences for host choice. We performed olfactometer
tests and morphology
comparisons to assess the adaptations of opportunists and specialists to their
carrier
hosts. The opportunist M. perglaber was shown to discriminate
between various qualities of dung. Opportunists are
thought to use this ability
when their carrier buries a new dung pat and they have to decide whether to
leave their
carrier to live in a
good-quality dung pat or to stay until the carrier finds another dung pat of
good quality. The specialist
M. saceri did not discriminate between
qualities of dung; specialists always stay on the body of their host, whatever
the dung quality. These
life-style features are thought to describe essential differences between
generalist and
specialist macrochelids. Also
morphometric parameters differed among three specialist and three generalist
species.
Relative to the generalists,
specialists had a larger body and longer PI legs (= first leg pair); both
characters are hypothesized
to be an advantage in active
searching for carrier hosts. Availability of carrier hosts is more likely
limiting to specialists
than to generalists. Small
size has the advantage of reaching more prey living inside the dense dung
material.
Key words: Macrocheles perglaber, Macrocheles saceri, olfactometer, morphometry,
host selection, phoresy,
Coprophily
Shinya
Nishimura1,†, Norihide Hinomoto2,* & Akio Takafuji1
1Laboratory of Ecological
Information,
address: Agricultural Chemical
Research Laboratory, Sumitomo Chemical Co., Takarazuka, Hyogo 665-0051,
2National Institute of
Agrobiological Sciences, Tsukuba,
p. 349
We developed seven microsatellite
markers for Tetranychus kanzawai (Acari: Tetranychidae) and examined how well
the isolated markers conformed
to Mendelian laws. All microsatellite markers fit the expected 1:1 disomic
segregation
ratio and hence were inherited
in a Mendelian fashion. Using these markers, we investigated spatio-temporal
gene flow among populations of
T. kanzawai on three host plants, Hydrangea macrophylla, Akebia quinata, and
Clerodendrum trichotomum. Temporal genetic variation
showed that population differentiation was slightly reduced
from April to May but greatly
increased from May to October. In the analysis of spatial genetic variation, no
isolation
by distance was detected among
the three host-plant populations. Gene flow between populations on H. macrophylla
and those on other host plants
was relatively restricted, whereas the populations on A. quinata and C. trichotomum
were almost panmictic. Genetic
differentiation among the populations was attributed to the effect of host
plants
rather than to the effect of
geographic distance among populations, suggesting the possibility of sympatric
host race
formation in T. kanzawai.
Key words: Tetranychus kanzawai, microsatellite markers, gene
flow, genetic variation, host race, sympatric speciation
57 Demographic and reproductive parameters of Polyphagotarsonemus latus in Carica
papaya
Martha
de Coss, Gabriel Otero-Colina1, Jorge E. Peña2 &
Ricardo Magallanes
Universidad Autónoma de
Chiapas, Facultad de Ciencias
Montecillo, Km 36.5 Carr.
2University of
p. 357
Cohorts of specimens of Polyphagotarsonemus latus were bred on seedlings of
papaya trees cv. Maradol under controlled
environmental conditions. This
was done to determine the effect of temperature and relative humidity on
population
and reproductive parameters of
P. latus, as well as the suitability
of papaya as a host. Developmental times of
P. latus at 25, 28, and 31 °C and 55,
67, and 97% r.h. were compared. Egg-to-adult developmental time varied between
2.81 and 4.93 days, which is
considered normal when compared to development on other host plants. The
intrinsic
rate of increase (rm) varied from 0.03 to 0.4,
depending on relative humidity and temperature. Papaya is considered a
suitable host, but temperature
and humidity outside the most favorable values considerably reduce the
potential of
the mite to colonize it.
Key words: Carica papaya, life table, fecundity table,
Tarsonemidae
Ibrahim
J. Al-Jboory & Taha M. Al-Suaide1
and 1Ministry of Science and
Technology, Jadrea,
p. 361
Oligonychus afrasiaticus is considered one of the major
pests threatening the production of dates in
between 50-80% yield loss in
years of dry, dusty, stormy weather. The biology of this mite was studied at
four constant
temperatures (20, 25, 30, and
35 °C), 50-60% relative humidity, and L16:D8 photoperiod. No development was
observed at 15 and 40 °C.
Incubation period peaked at 20 °C (7.6 days) and reached a minimum at 35 °C
(2.7 days),
development of larva,
protonymph, and deutonymph took 5.3, 4.3, and 4.5 days at 20 °C, and 1.9, 1.3,
and 1.4 days
at 35 °C, respectively. Number
of eggs/female was 12.5 at 20 °C and 27.2 and 35 °C. Longevity of female and
male was
33.2 and 29.1 days at 20 °C,
and 11.5 and 10.1 days at 35 °C, respectively. The results were used to
establish a life table
of this mite.
Key words: Old world date mite, Oligonychus afrasiaticus,
Ecological Acarology: Associations with Insects
Rostislav
Zemek & Radomír Socha
Biology Centre of Academy of
Sciences of the Czech Republic, Institute of Entomology, Branišovská 31, 370 05
Cveské
p. 367
The firebug Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)
is a polyphage whose European populations mainly feed
on the seeds of trees (Tilia cordata, T. platyphylos, Robinia pseudoacacia) or plants such as mallows
(Malvaceae). It is
frequently found on the ground
near host trees or at the base of their trunks. During summer, however, we
observed
many individuals to climb up
the trees. Movement of the bugs to upper parts of the trees and their
occurrence in
canopies have not been
reported so far and there is also no clear explanation for this behavior. We
formulated the
hypothesis that P. apterus switches habitat to find
optimal abiotic conditions for its development and to avoid the
ectoparasitic mite Hemipteroseius adleri (Otopheidomenidae). To test
this hypothesis we collected samples of adult
males and females of the
firebug from linden tree trunks at >1 m above the ground (tree habitat) and
from the ground
near these trees (ground
habitat). The insects were individually preserved in vials with ethanol and
examined using a
microscope. Eggs, larvae,
nymphs, and adults of H. adleri found
on each specimen were counted. The results revealed
that the bugs dwelling on
linden trees were nearly devoid of parasitic mites (only 5% were parasitized),
whereas 29%
of those collected on the ground
were parasitized. The mean numbers of H. adleri found on the respective groups
were clearly different. We
also tested whether P. apterus is
more likely to be infested by H. adleri during its final larval
ecdysis. Laboratory
experiments showed no differences between the infestation by the mite in adult
bugs and
adults emerged from the last
instars. We conclude that selection of a tree habitat in P. apterus might contribute to
reducing the risk of being
parasitized by H. adleri.
Key words: Hemipteroseius adleri, Pyrrhocoris apterus, insect parasites, avoidance
behavior, Otopheidomenidae
60 Mites associated with concealed and open nests of Apis cerana indica in Kerala,
M.A.
Haq, K. Sumangala1 &
Division of Acarology,
Department of Zoology,
E-mail: haqzas@yahoo.co.in;
and 1School of Engineering and
Applied Sciences,
p. 371
Apis cerana indica, the common Indian honeybee,
constructs nests in dark places, like hollow tree trunks, soil crevices,
shaded roofs, subterranean
holes, etc. In contrast to these concealed nests, also some open nests were
found in the
area of Malabar. Here,
parallel structures of 6-8 combs were observed hanging from branches of Anacardium occidentale
and Bambusa gigantea trees. An open nest may have
advantages to the bees in that they suffer less disturbance
from ectoparasitic and
phoretic mites. Moreover, they are less resticted in nesting space than when
their nests are
concealed in hollow trees,
termitaria, soil cracks, etc. It may also have advantages for apiculture. Beekeepers
and apicultural
researchers can regularly
observe colony organization, mobilization, propagation, parasitic invasion, and
parasite
resistance. Moreover, open
nests, being larger, may produce more honey and facilitate extraction of honey
without
much destruction of bees and
brood cells. A survey of mites was carried out on natural colonies of A. cerana indica,
covering various districts of
Kerala.
Key words: Apis cerana indica, phoretic mites, habitat
switching
Ecological Acarology: Invasive Species
61 Tracking the colonisation history of the invasive
species Varroa destructor
Maria J.
Navajas
Institut National de la
Recherche Agronomique, Centre de Biologie et Gestion des Populations, Campus
Baillarguet, CS
30016, 34988
p. 375
The development of molecular
tools and the theory of invasion genetics have stimulated interest in the study
of the
invasion of new environments
or new hosts by alien species. This approach has recently been applied to
better understand
the colonisation history of Varroa destructor, an invasive parasitic mite
that has dramatically expanded its geographical
distribution area after it
shifted from its original host, the Asian cavity-nesting Apis cerana, to the honey bee
A. mellifera during the last century. Varroa
is currently considered as the major pest of honey bees in most parts of
the world. Initial work found
little evidence of genetic variability in V. destructor. More recent work, taking
advantage
of the sequencing of the
mite’s complete mitochondrial (mt) genome, made it possible to define specific
PCR primers
for amplifying long DNA
fragments covering different mitochondrial genes. Mitochondrial sequences (a
total of 2,700
nucleotides) display
substantial polymorphism. In total 20 haplotypes were identified, representing
nucleotide diversity
of 0.75%. Interestingly, six of
them were detected in mites infesting A. mellifera and represented a nucleotide
diversity of 0.4%. This
contrasts with the remarkable homogeneity of the two haplotypes (known as the
Korean and
have managed to colonise A. mellifera worldwide (presumably carried
by humans), multiple shifts from its natural host
A. cerana to this species have occurred
in
invasion process are reviewed
and discussed, including the threatening possibility that additional genotypes
might
spread into A. mellifera in the future.
Key words: Mitochondrial haplotypes,
mircoratellites, genetic markers, invasion genetics, Varroa destructor
62 The rice mite Steneotarsonemus
spinki, an invasive species in the
Denise
Navia1, Renata Santos de Mendonça1 & Ronald Ochoa2
1Embrapa Recursos Genéticos e
Biotecnologia, Cx. Postal 02372, 70.770-900, Brasília, DF, Brasil.
E-mail:
navia@cenargen.embrapa.br; and 2Systematic Entomology
Laboratory, USDA-ARS, BA, PSI, Building 05, BARC-West,
10.300,
p. 379
The rice mite, Steneotartsonemus spinki Smiley, has been considered a
serious rice pest in several tropical Asian
regions since 1970. However,
it was in the
in
American countries. Damage
caused by S. spinki infestations
can be direct, as a consequence of toxin injection during
feeding, or indirect, through
the spreading of phytopathogens. At first, rice (Oryza sativa L.) was considered its only
host plant, but in
indicating its potential to
adapt to other hosts, especially Oryza species. There are indications that S. spinki can be disseminated
via trade of rice seeds or
naturally by wind, insects or birds. In
rice crops, involves mainly
cultural methods and resistant varieties. The introduction and establishment of
S. spinki in
South and
agrochemical applications for
pest control. Therefore, it is essential to reinforce the use of quarantine
measures in
order to avoid or to delay the
introduction of the mite pest into South and
plan for rice mite management
in the
Key words: Oryza sativa, rice, biosecurity,
63 Importation of a New World tick, Dermacentor albipictus (Acari:
Ixodidae), with a horse from the
Gabriele Liebisch, Arndt
Liebisch & Stephan Paufler
Laboratorium für klinische Diagnostik ZeckLab, Up’n
Kampe 3, D-30938, Germany. E-mail: liebisch@zecklab.de
p. 385
In February 2006 an American
Bashkir Curly horse was imported via air from
arrival at the
days in the stable in
Dermacentor albipictus, which is also called ‘winter
tick’. Hosts for the ticks are large wild and domestic mammals,
such as moose, cows, and
horses. On these animals the tick undergoes a one-host life cycle. Larvae
become active in
summer, nymphs and adults
engorge during November and February on the same host. This
occurs in woodlands of North
America up to 60° N in
environment for establishing a
tick population for D. albipictus.
From
Dermacentor marginatus and D. reticulatus, is known. This underlines
the importance for an exact species diagnosis
of ticks. Ticks of the genus Dermacentor include important vectors of
disease agents, such as viruses, rickettsiae,
Babesia, and Theileria. Unfortunately, there exist
no veterinary regulations by the EU (
prevention of importation of
ticks. The horse was treated with permethrin wipe-on. Additionally, all visible
ticks were
collected by hand dressing and
burned. Engorged female ticks were collected for experimental use. In an
outdoor
experiment female ticks laid
eggs under natural German winter conditions. Larvae emerged 25 weeks after
engorgement
of the females.
Key words: Dermacentor albipictus, importation, horse,
Agricultural Acarology: Biological Control
64 Concepts of classification
of the Phytoseiidae: Relevance to biological control of mites
J. A.
McMurtry
p. 393
Early phytoseiid mites
colonizing the plant habitat probably were generalized types with omnivorous
food habits.
Various life styles and ‘body
plans’ evolved, some adapted to exploiting certain foods, others to cope with
specific
plant characteristics. Marked
specialization for utilizing spider mites, producing copious webbing, as prey
probably
evolved independently in at
least four of the 16 tribes across two of the three subfamilies. Specialization
for other
types of mite prey is less
clear although some trends are evident. Species with generalist feeding habits
seem to be
predominant in nearly all
tribes. Two genera in the tribe Euseiini evolved unique characteristics
presumably for utilizing
pollen as a food source. Some
‘body plans’ seem more closely related to the morphology of the host plant than
to
food source. The tribe
Kampimodromini serves as an example of this feature. The classification system
of Chant &
McMurtry (1994, 2002-2006) is
examined in relation to the main genera containing species showing promise for
biological
control. Challenges at the
species level are discussed.
Key words: Phytoseiidae, phytoseiid
classification, biological control
65 Biological control of mites
in European vineyards and the impact of natural vegetation
Carlo
Duso, Serge Kreiter1, Marie-Stéphane Tixier1, Alberto Pozzebon &
Valeria Malagnini2
Department of Environmental
Agronomy and Crop Science,
(PD),
INRA/IRD/CIRAD/SupAgro, Campus
International de Baillarguet, CS 30 016, 34988 Montferrier sur Lez cedex,
2FEM, via E. Mach, 1 38010 San
Michele all’Adige (TN),
p. 399
In vineyards, generalist
phytoseiids are important in keeping phytophagous mites at economically
acceptable levels.
Among these predators, Typhlodromus pyri and Kampimodromus aberrans have proven to be most
effective, because
they increase in numbers in response
to mite pests and alternative prey/food, they persist under conditions of prey
scarcity, and they can
tolerate several fungicides and insecticides. Natural colonization of
commercial vineyards by phytoseiids
may take several years. Therefore,
strains showing field resistance to certain insecticides (e.g.,
organophosphates)
and fungicides (e.g.,
mancozeb) are of practical interest. Here we report results obtained with
releasing T. pyri
and K. aberrans strains with different
pesticide histories, with emphasis on factors affecting their persistence,
i.e., alternative
food availability (pollen or
downy mildew), leaf morphology, and selective pesticides. Natural vegetation
surrounding
vineyards may impact the
densities of phytoseiids in neighbouring crops. For example, phytoseiid
densities on
plants surrounding vineyards
under IPM in
and K. aberrans density appeared positively
affected by high trichome densities and presence of domatia. Also
pollen density was
significantly correlated with trichome density and domatia (hair tufts). Predatory
mites disperse
mainly by air currents and
hence their dispersion depends on wind intensity and direction. Crop
colonization potential
(speed, intensity, uniformity)
was directly associated with phytoseiid densities and the proximity of natural
vegetation.
A deep, dense, and tall woody
area with suitable host plants constitutes the stablest source of phytoseiids. Natural
colonization
of vineyards by phytoseiid
mites has great potential and it may well be promoted by careful management.
Key words: Phytoseiids, Kampimodromus aberrans, dispersal, colonisation,
woody areas, hedges, leaf morphology,
pollen, fungi, IPM
66 Does agroforestry affect
phytoseiid mite communities in vineyards in the South of France?
Ziad
Barbar, Marie-Stéphane Tixier, Brigitte Cheval & Serge Kreiter
ENSA.M–INRA, Unité d’Ecologie
animale et de Zoologie agricole, Laboratoire d’Acarologie, 2 Place
p. 409
The abundance and diversity of
phytoseiid mites were surveyed from April to September 2003-2005 in several
grape
crops in the South of France,
with Grenache and Syrah cultivars, co-planted with rows of Sorbus domestica or Pinus
pinea and in plots with monocultures
of grapes. Densities of phytoseiid mites differed on the two tree species. Pinus
pinea seemed to be a better host
than S. domestica. Typhlodromus exhilaratus was the dominant species in
the crops
and on co-planted rows of S. domestica and P. pinea, whereas T. phialatus was the most abundant species
in plots
with monocultures of trees.
Agroforestry management does not seem to affect mite diversity in vine plots. The
densities
of phytoseiid mites in vine
crops may well be affected by the co-plantation of trees, especially in 2005. Although
the densities observed during
2003 and 2004 were probably low due to very dry and hot climatic conditions,
the agroforestry
management seems to have had a
significant impact on mite densities in 2005. Further experiments should
be carried out to confirm this
effect.
Key words: Phytoseiidae, Typhlodromus exhilaratus, Typhlodromus phialatus, vineyards, Pinus pinea, Sorbus domestica
67 Manipulating
plant-arthropod conversations to improve conservation biological control of
mites
David G.
James, Sandra
Reyna,
Oscar Garcia & Joe Perez
Department of Entomology,
p. 413
The potential of using
synthetic herbivore-induced plant volatiles (HIPV) (e.g., methyl salicylate,
tool to enhance conservation
biological control of mites is being researched in commercially grown hops in
of synthetic
Coccinellidae), Orius tristicolor (Hemiptera: Anthocoridae), Geocoris pallens (Hemiptera: Geocoridae), Deraeocoris
brevis (Hemiptera: Miridae), Chrysopidae,
Hemerobiidae, Nabidae, Thripidae. The enhanced community of mite predators
controlled spider mite
populations in MeSA-baited hops without miticide intervention. All unbaited
blocks
required at least one miticide
for spider mite control. Direct application of natural
plants contained in canola oil
or rosemary/peppermint oil pesticide formulations, resulted in greater
attraction of two
mite predators (O. tristicolor and Stethorus spp.) to treated than to untreated
plants. MeSA-mediated stimulation of
the plants to produce
predator-attracting volatiles is suggested as the likely mechanism. The use of
synthetic or natural
versions of
HIPV/plant-signaling compounds like
has the potential to provide a
novel yet practical strategy for improving the efficacy and reliability of
conservation biological
control of mites in a variety
of agricultural ecosystems.
Key words: HIPV, HIPPO, methyl
salicilate, synthetic lure, hop, multitrophic interaction, integrated mite
management
68 Status of coconut mite Aceria guerreronis and biological control research in
L.C.P.
Fernando & N.S. Aratchige
Coconut Research Institute,
p. 419
The coconut mite, Aceria guerreronis (Acari: Eriophyidae), invaded
areas infesting 17% of the
total coconut extent by 2005. It is more prevalent in the dry zone than in the
intermediate
and wet zones. Within each
year, populations fluctuated with high peaks in June-August and relatively low
levels in
November-February. Neoseiulus baraki and N. paspalivorus (Phytoseiidae) are the most
common predatory mites
found beneath the bracts of
infested coconuts; N. baraki is
found in higher proportions in drier areas, N. paspalivorus
in wet and intermediate areas,
occasionally in cooler pockets of the dry areas. Populations of N. baraki constantly
increased in the period
2000-2005 and their fluctuating numbers followed a pattern similar to that of
coconut mite.
This strong interrelationship
suggests that N. baraki is
a prospective candidate for control of coconut mites. Its use
involves mass breeding and
field release techniques. It turned out that N. baraki could be mass-reared in
laboratory
arenas on Tyrophagus putrescentiae (Acari: Acaridae). Mass
releases of lab-reared N. baraki increased
its numbers
and reduced coconut mite
numbers in the field, up to a period of 4-6 weeks after release. Also the use
of the entomopathogenic
fungus Hirsutella thompsonii was explored. The most
effective isolate persisted for up to 16 weeks on
the nuts. Over 90% of the nuts
had low numbers of live coconut mites up to 4 weeks after treatment. The trials
indicate
that either biological control
agent lacks the ability to suppress the coconut mite for a longer period. Hence,
frequent
applications of these natural
enemies and/or interventions by use of low toxic chemicals may be required for
sustainable control.
Directions in biological control research of coconut mite are discussed.
Key words: Aceria guerreronis, biological control, coconut,
distribution, population fluctuations,
Eric
Palevsky1, Phyllis G. Weintraub2, Einat Zchori-Fein1,
Shira Gal1, Neta Mozes-Daube1, Yael Argov3,
Marisa Castagnoli4, Marialivia Liguori4, Roberto Nannelli4,
Sauro Simoni4, Franca Tarchi4, Silvia Guidi4,
Donatella Goggioli4, Giuseppino Sabbatini Peverieri4,
Peter Schausberger5, Andreas Walzer5, Monika Enigl5,
Serge Kreiter6, Marie-Stéphane Tixier6, Sabine Guichou6,
Karel Bolckmans7, Yvonne van Houten7, Elmer van Baal7,
Jose Eduardo Belda8, Shimon Steinberg9, Nurit Shapira10,
Dimitrios Charantonis11, George Tsalis11, Raija Holmqvist12,
Sune Gullans12, Michael Gross13, Patrick Peternel13,
Jan van der Blom14, Juan Carlos Perez Mesa14, Gad
Rosenthal15 & Ofra Goldfarb15
1 Dept. of Entomology,
Agricultural Research Organization (ARO), Ministry of Agriculture, PO Box 1021,
Ramat Yishay 30095, Israel. E-mail: palevsky@volcani.agri.gov.il; 2Dept.
of Entomology, ARO, Ministry of Agriculture, Gilat Research Center, D.N. Negev,
85280 Israel; 3Israel Cohen Institute for Biological Control
(ICIBC), Plant Production and Marketing Board, Citrus Division, Derech
Ha'macabim 46, Rishon Le Zion 75359, PO Box 54, Beit Dagan 50250, Israel; 4CRA-Istituto
Sperimentale per la Zoologia Agraria (ISZA), via di Lanciola 12/A, Firenze
50125, Italy; 5Institute of Plant Protection, Department of Applied
Plant Sciences and Plant Biotechnology, University of Natural Resources &
Applied Life Sciences (BOKU), Peter Jordanstrasse 82, A-1190 Vienna, Austria; 6Montpellier
SupAgro, 2 Place Pierre Viala, 34 060 Montpellier cedex 01, France; 7Koppert
Beheer, Veilingweg 17, 2650 AD Berkel en Rodenrijs, The Netherlands; 8Koppert
España, c/Cobre 22, Pol. Ind. Ciudad del Transporte, 04745 La Mojonera
(Almeria), Spain; 9Bio-Bee Biological Systems, Kibbutz Sdeh Eliyahu,
Beit Shean Valley, 10810, Israel; 10ARV Development Company, Sapir
Center, M.P. Arava, 86825, Israel; 11Charantonis Biological Crop
Protection, 35, Safrapoleos Str., 585 00 Skydra, Greece; 12Oy
Schetelig AB, Tiilitie 14, FIN- 01720 Vantaa, Finland; 13Biohelp,
Kapleigasse 16, A-1110 Vienna, Austria; 14Coexphal, Ctra. de Ronda,
11-1º E, Apto. 330, 04004 Almeria, Spain; and 15Kivun, 116 Menachem
Begin Rd., Beit Kalka, PO Box 7201, Tel Aviv, Israel
p. 425
Neoseiulus californicus (McGregor) is a relatively
effective phytoseiid predator against spider mites reported from the
and mass-rear a strain of N. californicus that is more efficacious under
arid conditions than the standard commercial
strain from California (USA). N. californicus strains were collected in arid
areas worldwide. Discriminant analysis
performed with 30
morphological variables allowed for their separation. The performance of these
strains under arid
conditions and on selected
host plants was evaluated in laboratory and semi-field trials. Development and
survival of
eggs and juveniles differed
among strains and humidities. Female performance (survival, oviposition) was
influenced
by strain but not by humidity.
The Californian reference strain was superior to all others, when considering
both adaptation
to dry conditions and power of
population increase at low humidities. Whole potted plant trials (cucumber,
strawberry, and pepper)
confirmed this result. Field trials were conducted to compare this new product
to the standard
commercial strain of Phytoseiulus persimilis Athias-Henriot. To identify
possible influence of symbiotic bacteria
on strains of N. californicus general primers for the 16S
rDNA gene were used in a PCR. Among other bacteria, a
Spiroplasma, closely related to the one
found in various arthropods, was detected in two strains, and it was further
characterized. No influence on
the host's developmental time, fecundity, and sex ratio could be detected. To
provide
this product at an affordable
cost for European growers an economic rearing and delivery system for N. californicus
was developed and its
marketing potential in
Key words: Phytoseiidae, intra-specific
variation, mass-rearing, symbionts
70 Host Range, distribution,
and morphometrics of predatory mites associated with phytophagous mites of
fruit crops in
Meena
Thakur, C.L. Dinabandhoo & Usha Chauhan
Department of Entomology and
Apiculture, Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni,
Solan-173 230
(Himachal Pradesh),
p. 431
A survey on host range and
distribution of mite species associated with fruit crops was carried out during
1999-2001
at different altitudes and
districts of Himachal Pradesh. Eight species of predaceous mites (mostly
Phytoseiidae) were
found in association with 11
species of phytophagous mites (mostly Tetranychidae). Panonychus ulmi was the major
phytophagous species on apple
at Shimla district, other pests included Tetranychus urticae, Bryobia rubrioculus,
Brevipalpus californicus, and Aculus malus, whereas T. urticae was dominant on apple and
other pome and stone
fruits at Kullu district. At
Shimla district the predaceous mite Amblyseius finlandicus was abundant and associated
with
P. ulmi, B. californicus, A. malus, and Tetranychus species on apple, pecan nut,
and walnut. At Solan district Amblyseius
longispinosus was prevalent. Its host range
was restricted to Tetranychus species
on fig, papaya, apple, and beans.
Phytoseius crinitus was abundant on guava and
citrus, infested with Brevipalpus phoenicis at Una district. Phytoseius
intermedius was the dominant predatory
mite associated with litchi leaves having well developed erinia due to Aceria
litchi. Typhlodromus homalii was found in mixed population
of P. intermedius on
litchi leaves infested with A. litchi
from Kangra district. Agistemus sp. was collected from apple
leaves infested with T. urticae at
Shimla, from cherry and
walnut with T. urticae at Kullu, and from guava and
citrus infested with B. phoenicis at
Una. At Mandi district Tydeus
sp. was present along with A. finlandicus (5 mites per 25 leaves) in
mango orchards infested with T. urticae. Biscirus
sp. was collected on grapes
and citrus leaves. Morphometrics and diagnostic features of different species
are presented
in the paper.
Key words: Faunistics, orchard, species
diversity, fruit trees
71 Winter survival and reproduction of Amblyseius longispinosus (Acari:
Phytoseiidae), a potential predator of spider mites on roses in
Usha
Chauhan, Ram Kumar & Meena Thakur
Department of Entomology and
Apiculture, Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni,
Solan-173 230
(Himachal Pradesh),
p. 435
Amblyseius longispinosus is an effective predator for
the control of two-spotted spider mite, Tetranychus urticae, on
roses. It feeds on all stages
of the spider mite but it prefers nymphs and adults to eggs. The predatory
mites were kept
under laboratory conditions on
excised, mite-infested rose leaves. Under winter conditions (T-min 0.5-5.9 °C,
T-max
18.4-22.7 °C, 20-91% relative
humidity), the predatory mite completed egg-to-adult development in 8.8 days. Egg,
larva, protonymph, and
deutonymph stages took 3.8, 1.3, 1.7, and 2.0 days, respectively, and adults
survived for 19.4
days. Within 2 days after
emergence of the adults, mating took place, each copulation lasting only 7-8
min. Mean
fecundity was 11.2 eggs per
female and all eggs hatched successfully. Thus, A. longispinosus, can survive and reproduce
under winter conditions
prevailing mid-hill in Himachal Pradesh. It may therefore be a candidate for
control of
two-spotted spider mites in
areas with a temperate climate in
Key words: Amblyseius longispinosus, biology, winter months,
oviposition, Tetranychus urticae
72 Effect of the entomopathogenic fungus Beauveria bassiana on three acarine
pests
Abd-Allah
M. Afifi, Aiman M. Mabrouk & Amal A. Asran1
Agric. Zoology Dept., Fac.
Agriculture,
Institute,
p. 439
The entomopathogenic fungus Beauveria bassiana (Balsamo) as control agent of
European red mite, Panonychus ulmi
Koch, citrus rust mite Phyllocoptruta oleivora (Ashmed), and two-spotted
spider mite Tetranychus urticae Koch was
investigated. Fungal spore
suspensions at 2×106
and 2×108 spores/ml were applied to P. ulmi and Ph. oleivora. Mite
mortality increased with an
increase in spore concentration and exposure time; 14 days after treatment with
2×106
and 2×108 spores/ml, average mortality
was 62.5 and 83.3% for P. ulmi,
and 82.6 and 91.7% for Ph. oleivora,
respectively.
Spore suspension (2×108) was applied to citrus fruits
and leaves to control citrus rust mite under field conditions.
Seven days after spraying
fruits and leaves, respectively, reduction of the mite population was 74.9 and
72.5%,
and after 14 days 83.8 and
85.8%. Spore suspension (2×106) was also applied to
cotton plants (cultivars
and 83) in the field, to
control T. urticae.
Spider mites on
the other two cultivars; 14
days after treatment, the mite population was reduced by 67.9, 78.4, and 66.5%
on
70, 45, and 83, respectively.
Key words: Entomopathogenic fungi,
biological control, Beauveria bassiana,
Tetranychus
urticae, Phyllocoptruta
oleivora, Panonychus ulmi
73 Hirsutella
thompsonii as a mycoacaricide for Aceria guerreronis on coconut in
P.
Sreerama Kumar
Project Directorate of
Biological Control, HA Farm Post,
E-mail: psreeramakumar@yahoo.co.in
p. 441
Since 1998, the coconut mite, Aceria guerreronis, has been a chronic
constraint to coconut farming in
largest producer of coconuts
in the world. From the beginning, biological control has been perceived as the
most sustainable
method for its management,
despite the availability of several alternatives such as chemical and botanical
pesticides, and
nutrition-based cultural methods. Intensive research resulted in the
identification of the mite-specific
fungal pathogen, Hirsutella thompsonii, as the most important
natural regulator of the coconut mite, and this subsequently
led to the development of
Mycohit, a powder formulation of the fungus. The pathogen has been evaluated
as a short-term as well as a
long-term biocontrol agent since 2000. Spraying of the product on young bunches
resulted
in high fungus-associated
mortality of the mite in many locations. Two liquid variants of the
formulation, viz.
Mycohit-LG20 and -OS, were
also evaluated across four south Indian states. The fungus was found to be
capable of
bringing down the mite
population up to 90%, resulting in considerable reduction in pre-harvest nut
damage. In several
trials, the fungal treatment
was superior to azadirachtin, dicofol, triazophos, and/or wettable sulphur.
Key words: Aceria guerreronis, coconut, eriophyid mite, Hirsutella thompsonii, mycoacaricide
Gunasingham
Mikunthan & M. Manjunatha1
Department of Agricultural
Biology, Faculty of Agriculture,
gmikunthan@gmail.com, and 1Department of Entomology,
Shimoga 577201,
p. 445
Aceria guerreronis (Acari: Eriophyoidea) inflicts
severe damage on the nuts of commercial coconut palms.
Investigations were carried
out in
Mite-infested nuts were collected,
brought to the laboratory, and examined for the presence of fungi associated
with A. guerreronis. Cadavers showing mycelial
growth were surface sterilized and inoculated into potato dextrose
media. Fusarium sp. was isolated from the
cadavers. Biorationals such as Azadirachtin Fusarium semitectum,
Fusarium sp. isolate GM15, Lecanicillium lecanii, Beauveria bassiana, Metarhizium anisopliae, and Trichoderma viride,
plus the regularly used
pesticide Abamectin, were evaluated for their impact on A. guerreronis. The benign control
experiment involved spraying
equal amounts of distilled water. All treatments were applied to the crown area
of
the palms in the field and
mites were counted by detaching nuts from the inflorescence prior to spraying
as well as 7,
15, and 23 days after
spraying. On day 23 after spraying, Fusarium sp. isolate GM 15 and F. semitectum were the most
effective, with 94 and 79%
mite population reduction relative to the water control, respectively. Azadirachtin
(66%)
was the next most effective,
but Abamectin and L. lecanii were
less effective. To establish an eco-friendly management
of A. guerreronis, the two isolates of Fusarium sp. seem the best
biorationals.
Key words: coconut mite, biorational,
pathogenicity, Fusarium,
Aceria
guerroronis
Agricultural Acarology: Pesticides and Biological
Control
75 Biocontrol of phytophagous
mites in
Noubar
J. Bostanian, Gaétan Racette & Jacques Lasnier1
Horticultural and Development
Centre, Agriculture & Agri-Food Canada, 430 Gouin Blvd. St.
Jean-sur-Richelieu, Quebec,
p. 451
During the 1980s biocontrol of
phytophagous mites was based on the mass rearing and inundative releases of
predators
in orchards. This approach was
found to be unreliable and impractical on a large scale. Since 1990 a highly
robust
grower-friendly philosophy for
biocontrol of phytophagous mites in orchards has been initiated, based on the
conservation,
re-colonization, and
augmentation of several naturally occurring predacious mites in the field. The
success of
this approach is based on a
comprehensive understanding of the toxicology of all pesticides used to manage
arthropod
pests and diseases of apple. This
information is relayed by pamphlets to growers who prepare their own pest
management programs, with the
help of extension agents. A simple technique has also been developed to
transfer
pruned winter- and summer-wood
from a donor orchard where biocontrol of mites has been established to a
recipient
orchard where biocontrol is in
the process of being established.
Key words: Biocontrol, phytophagous
mites, predacious mites, orchards, apples
Serge
Kreiter, Philippe Auger & Romain Bonafos1
UMR Centre de Biologie et de
Gestion des Populations, Montpellier SupAgro/Institut National de la Recherche
Agronomique, 2 Place
transfert, Montpellier
SupAgro/Institut National de la Recherche Agronomique,
p. 457
Using the methodology of the
French AFPP/CEB guideline no. 167 for testing side effects of pesticides on
Typhlodromus pyri, we review the results
obtained with laboratory trials for more than 120 pesticides. Most of the
insecticides/acaricides tested
were found to be toxic and most of the fungicides non-toxic or slightly toxic. These
results provided a good
indication of the toxicity assessed in field trials. To put this relation to
the test, we carried out
a more in-depth study on the
fungicide mancozeb and its toxicity to phytoseiids in vineyard and orchard. Side
effects
of this fungicide were studied
on T. pyri in
the laboratory and in 4-year field trials in several grape crops. In vineyards
where mancozeb had commonly
been used over the years, this fungicide is generally slightly toxic. However,
in plots
where it had never been used,
its effect on populations of T. pyri was more pronounced and varied from moderately
toxic to toxic. Despite its
intrinsic toxicity, populations were never eradicated. Laboratory results
confirmed the field
trial results. Even though
toxicity of mancozeb is higher in lab trials, a significant correlation was
established between
field and laboratory results
for all strains of T. pyri.
It is striking to observe that – despite the intrinsic toxicity of not
only mancozeb, but also
pyrethroids and organophosphates – densities of T. pyri and Amblyseius andersoni in grape
crops in the Region
Midi-Pyrénées are commonly high. Our laboratory tests indeed showed that
strains of these two
species are resistant to
deltamethrin, ë-cyhalothrin, and
chlorpyriphos-ethyl, which probably explains their abundance
in grape crops in this area.
Key words: Side effects, resistance,
mancozeb, deltamethrin, ë-cyhalothrin,
chlorpyriphos-ethyl, Typhlodromus pyri,
Amblyseius andersoni
77 Pesticide side-effects on
predatory mites: the role of trophic interactions
Alberto
Pozzebon & Carlo Duso
Department of Environmental
Agronomy and Crop Science,
p. 465
The control of spider mites in
protected crops is often critical due to the development of mite resistance to
acaricides.
Studies of the side-effects of
pesticides on beneficial mites are required in order to improve integrated
spider mite
management. Pesticide
side-effects on predatory mites of the family Phytoseiidae can be studied at
the field or laboratory
level. In the field,
phytoseiid abundance can be related to the presence of prey and/or alternative
foods, which
can affect the response of
predatory mites to pesticides. We investigated whether pesticide side-effects
on phytoseiids
may be mediated by trophic
interactions. In the laboratory we evaluated the effects of two insecticides
(derived
from pyrethrins and Beauveria bassiana) on the predatory mite Phytoseiulus persimilis by testing the same under
various
exposure conditions (leaf
residues, treated prey, topical application). The effects of these insecticides
on P. persimilis
were higher when the predators
were fed with treated prey. Furthermore, we investigated the effects of
pyrethrins on the predatory
mite Amblyseius andersoni on vines with low or high incidence of the plant pathogenic
fungus Plasmopara viticola (grape downy mildew, GDM). GDM
mediated interactions between pyrethrins and A.
andersoni since it is alternative food
for this predatory mite. The implications of these studies for the development
of
toxicological methods and
integrated pest management are discussed.
Key words: Pesticide side-effects,
Phytoseiidae, Tetranychidae, Amblyseius andersoni, Phytoseiulus persimilis,
Tetranychus urticae, pyrethrins, Beauveria bassiana, grape downy mildew,
alternative food, IPM
78 Integrating pesticides and
biocontrol of mites in agricultural systems
Frank G. Zalom & Francisco
Javier Sáenz-de-Cabezón Irigaray
Department of Entomology,
E-mail: fgzalom@ucdavis.edu
p. 471
Integration of a biocontrol
agent into most agricultural systems will not be successful unless the natural
enemy can
survive the pesticides used in
that crop system. Knowledge of pesticide selectivity to beneficial arthropods
is important
to their utility in IPM
programs. Phytoseiid mites are effective as biocontrol agents in
Galendromus occidentalis and Phytoseiulus persimilis are among the most important –
the first species is native
to the western US, the latter
has become established in coastal
pyrethroids, in particular,
affect the abundance of G. occidentalis in almond through both contact and residual activity.
Harmful residues existed for
over a year on bark, and for 5 months on treated leaves. Several new acaricides
have
been registered for use in the
has enjoyed dramatically
increased use as replacement for the older products. Understanding the acute
and side
effects of these new products
is important to their successful integration into conservation and augmentation
programs.
Our recent research was
devoted to characterizing the direct and residual effects of a number of new
acaricides
on survival, fecundity and
fertility of G. occidentalis and
P. persimilis. Total effect on adult female
reproductive
potential was calculated and
categories for persistence were assigned following IOBC guidelines. Of these
acaricides,
etoxizole and fenpyroximate
had the greatest total effects on both species. Abamectin had the least total
effect on G.
occidentalis, and acequinocyl had the least
total effect on P. persimilis.
Key words: Phytoseiidae, Galendromus occidentalis,
Phytoseiulus persimilis, selectivity, side effects, abamectin, acequinocyl,
etoxazole, fenpyroximate
79 The impact of sulfur on
biological control of spider mites in
David G.
James & Deirdre Prischmann*
Department of Entomology,
Agricultural Research Service,
Northern Plains Area, North Central Agricultural Research Laboratory,
p. 477
Data collected from field
studies and experiments conducted in
2001-2005 indicate that the
multiple use of sulfur as a tool to manage powdery mildew, has an adverse
impact on biological
control of spider mites. In
vineyards there appears to be a positive correlation between the frequency of
sulfur
applications and spider mite
population densities. Multiple (>4) applications of sulfur can result in
spider mite population
outbreaks requiring control.
Similarly, in replicated vineyard and hop yard experiments, multiple
applications
of sulfur increased spider
mite populations. Conversely, predatory mite (Phytoseiidae) populations are
smaller in sulfur-
exposed hops and grapes than
in non-exposed plants, and it is likely that suppression of phytoseiid
populations by
multiple applications of
sulfur contributes to spider mite population outbreaks in
Key words: Side effect, Tetranychus macdanieli, powdery mildew
80 Impact of new pesticide
chemistry on acarine communities in apple orchards
Raul T.
Villanueva1 & James F. Walgenbach2
1Department of Plant Pathology,
NC State University, Don Ellis Laboratories, 1320 Varsity Drive, Raleigh, NC
27695, USA.
E-mail:
Raul_Villanueva@ncsu.edu; and 2Mountain Horticultural
Crops Research and
Drive, Fletcher,
p. 483
Changes in the acarine
community of several apple orchards due to adoption of new arthropod pest
control practices
were examined over a 4-year
period in western
pest management (IPM) program
was compared to a conventional IPM plot. In addition to pheromone-based
mating disruption,
reduced-risk plots also included one or more of the following new insecticides:
the nicotinoids imidacloprid,
thiamethoxam, acetamiprid, and
thiacloprid; the oxadiazine indoxacarb; the biological insecticide spinosad;
and the insect growth
regulators methoxyfenozide, novaluron, and pyriproxyfen. Conventional plots
were treated
with broad-spectrum
organophosphate, carbamate, and pyrethroid insecticides. The most common
phytophagous
mite was Panonychus ulmi, and the most prevalent
predators were the phytoseiid Neoseiulus fallacis (>99%) and the
stigmaeid Agistemus fleschneri. Results showed that
phytophagous mite outbreaks did not occur in the reduced-risk
plots, and acaricides were
applied 15 and 7 times in the conventional and reduced risk treatments,
respectively,
throughout the four-year
study. Phytoseiid and stigmaeid predatory mites were more abundant in
reduced-risk vs.
conventional plots. High
numbers of the mite-eating thrips, Scolothrips sexmaculatus, were noticed in one orchard
in
2004 and they were more
abundant in reduced-risk vs. conventional plots. In addition, crop protectant
aluminum silicate
clay (Surround® WP) negatively
affected phytoseiid mites compared to a control involving a water spray.
Key words: Reduced risk insecticides,
Tetranychidae, Phytoseiidae, IPM, Panonychus ulmi, Neoseiulus fallacies,
Agistemus fleschneri, Scolothrips sexmaculatus
Gunasingham
Mikunthan & M. Manjunatha1
Department of Agricultural
Biology, Faculty of Agriculture,
E-mail: gmikunthan@gmail.com;
and 1Department of Entomology,
Agriculture, Shimoga 577201,
p. 489
Chili crops suffer from damage
by the broad mite, Polyphagotarsonemus latus, and they also harbour a predatory
mite, Amblysius ovalis, as a potential control
agent. To understand the change in the population of these mites when
applying the acaricide
monocrotophos and an acaropathogenic fungus, Fusarium semitectum, experiments were conducted
in
(formulated in oil emulsion
and dust water; 108
spores/ml) were
sprayed in the field on the chili variety ‘Byadagi’,
commonly used in Karnataka (
the chili crop. Dry chili
yield was used for comparison of the treatments. Overall mite population
estimation indicated
that F. semitectum was effective to suppress
broad mites, either alone or in combination with monocrotophos.
The combination of F. semitectum with the recommended dose of
monocrotophos (0.05%) best suppressed P. latus,
whereas it did not affect A. ovalis numbers. Dust-water
formulation of F. semitectum in
combination with 0.05%
monocrotophos suppressed broad
mites better than the one mixed with a sub-lethal dose (0.025%) of the
toxicant.
The predatory mite population
was not affected by F. semitectum nor
by monocrotophos. Oil-emulsion formulation
was as effective as the
combination of dust water formulation and monocrotophos in both seasons. Considering
the
chili dry yield of all
treatments, the fungal formulation sprayed in combination with monocrotophos
(1.06 t/ha) gave
the best control followed by
the monocrotophos alone treatment (0.78 t/ha). Oil-emulsion formulation
obtained the
highest benefit-cost ratio
(6:1) which suggests that the application of the oil formulation against the
mites is feasible.
Key words: Monocrotophos, Fusarium semitectum, chili, Polyphagotarsonemus latus, Amblyseius ovalis
82 Compatibility of pesticides with the
acaropathogenic fungus, Fusarium
semitectum
Gunasingham
Mikunthan & M. Manjunatha1
Department of Agricultural
Biology, Faculty of Agriculture,
E-mail: gmikunthan@gmail.com;
and 1Department of Entomology,
Agriculture, Shimoga 577201,
p. 493
Acaropathogenic microbes
should be compatible with other control methods to be able to effectively
utilize them
against crop pests. This study
aimed to assess whether different pesticides used in the chili ecosystem are
compatible
with Fusarium semitectum, a potential mycopathogen
naturally infective to the active stages of the broad mite,
Polyphagotarsonemus latus. A selection of pesticides
easily available to farmers in local stores were prepared at 50,
100, 500 and 1,000 ppm. F. semitectum was inoculated on agar plates
and the inhibitory effect on radial mycelial
growth compared to a water-treated
control was assessed Fungicides and insecticides were moderately inhibitory and
equally toxic (on average, 41
and 37%, respectively) to F. semitectum, but dicofol, the one acaricide tested, was less
toxic (27%). Out of nine
fungicides carbendazim and benomyl were detrimental (54.5 and 53.3%
inhibition).
Conversely, copper oxychloride
and sulphur were comparatively harmless to F. semitectum. Our results underline that
compatibility of pesticides
with the F. semitectum should
be considered when selecting pesticides for use in addition
to F. semitectum to control broad mites and
mite pests in general.
Key words: Compatibility, Fusarium semitectum, pesticides, suppression,
acaropathogenic fungus
N.
Nusartlert, P. Vichitbandha1, G.T. Baker2 & A.
Chandrapatya
Department of Entomology,
Faculty of Agriculture,
E-mail:
chandrapatya@yahoo.com; 1Biology Division, Science
Section, Faculty of Arts and Science,
Kamphaeng Saen Campus,
Pathology,
p. 495
The life history of Neoseiulus longispinosus (Evans), a common predaceous
mite on various plants in central, eastern,
and southern
larvae of Tetranychus kanzawai Kishida, T. truncatus Ehara, T. urticae Koch, Eutetranychus africanus (Tucker),
Oligonychus mangiferus (Rahman et Sapra), or O. simus (Pritchard et Baker) were
provided as prey on excised mung
bean, cassava, strawberry,
tangerine, mango, and sugarcane leaf arenas, respectively. The predator completed its
development on each of these
prey, except for the eggs of O. mangiferus. Larvae were observed to feed after hatching.
To develop from egg to adult,
this predator required minimally 3.2±0.3 days when fed T. truncatus eggs or E.
africanus larvae, and slightly more when
fed eggs of E. africanus.
Females reared on various stages of T. truncatus lived
22.0±2.8 days, during which
47.1±8.8 eggs/female were laid (= 2.6±1.1 eggs/female/day). Ten commonly used
pesticides
were sprayed on N. longispinosus and mortality was assessed
after 24 h for larvae, nymphs, unmated females,
and gravid females. Egg
mortality was checked after 3 days. Almost all pesticides tested were toxic to
all stages of N.
longispinosus. The only exception was
Nissourun®, which caused 12.4 and 56.5% mortality of eggs and gravid females,
respectively.
Key words: Neoseiulus longispinosus, spider mite, life history,
fecundity, pesticide
Agricultural Acarology: Host Plant Effects and Damage
Sangita
Sharma & S.P. Bhardwaj
Regional Horticultural
Research Station, Dr Y.S. Parmar University of Horticulture & Forestry,
Mashobra, Shimla-171 007
(Himachal Pradesh),
p. 501
The European red mite, Panonychus ulmi (Koch), has assumed the status
of major pest in recent years in Himachal
fluctuation in relation to
host plant nutrition. The effect of three levels of N, P, and K, each at the
recommended dose
(N1, P1, K1), 25% above (N2, P2,
(N0P0K0) was studied on the build-up
of P. ulmi populations
on potted apple cultivars ‘Delicious’ at RHRS, Mashobra,
Shimla (2,286 m above sea
level). Among ten combinations of NxPxKx, the lowest mite population
was recorded at
N3P2K2 (i.e., 25% less than
recommended N and 25% more than recommended P and K), with 21.9 adults, 29.2
immatures,
and 103.2 eggs/leaf. In the
control treatment (N0P0K0), 40.0 adults, 44.3
immatures, and 166.3 eggs were
obtained. Treatment
combination N2P3K3 supported the largest
population of 74.8 adults, 91.8 immatures, and 320.9
eggs/leaf, significantly
different from the other treatments. These results suggested that slight
manipulation in the recommended
doses of NPK fertilizers can
contribute substantially to controlling the abundance of P. ulmi population on
apple trees.
Key words: Population development,
Delicious, plant nutrition, mite control, orchard pest
Abd-Allah
M. Afifi, Ahamed Y.M. El-Laithy1, Saied A. Shehata2 &
El-Sayed M.A. El-Saiedy1
Agricultural Zoology
Department, Faculty of Agriculture,
Protection Department,
Agriculture,
p. 505
Strawberry plant resistance to
infestation with the two-spotted spider mite, Tetranychus urticae Koch was investigated,
using two cultivars: Sweet
Charlie (Sw-cv) and Camarosa (Ca-cv). Ca-cv is more susceptible to infestation
with T.
urticae than Sw-cv. Chemical analysis
of leaves revealed that total phenols and amino acids were higher in Sw-cv than
in Ca-cv in, whereas the
opposite was recorded for total sugars. An increase in total phenol content
likely suppressed
mite infestation, whereas
increase of total sugars may have a stimulatory effect on spider mites. Leaf
trichomes of Swcv
have a higher density and are
longer and sharper pointed than those of Ca-cv. Such dense and long-hairy
leaves of
Sw-cv were not conducive to mite
infestation. Also when the two cultivars were fertilized with CaSO4 and K2SO4, mite
infestation was lower than on
unfertilized plants. These treatments lead to an increase in total phenols and
amino
acids in both cultivars.
Increased potassium levels in strawberry plants lead to an increase in plant
resistance to T.
urticae infestation. Moreover,
fertilization with CaSO4
and K2SO4 gave an increased strawberry
yield, of 7-17% for Swcv
and 6-22% for Ca-cv.
Key words: Strawberry, resistance, Tetranychus urticae, fertilization, trichomes
86 Weight loss of copra due to infestation by Aceria guerreronis
M.A. Haq
& T.R. Sobha1
Division of Acarology,
Department of Zoology,
E-mail: haqzas@yahoo.co.in;
and 1School of Biosciences, Safi
Institute of Advanced Study, Vazhayoor,
673633
p. 509
The commonly known coconut
mite, Aceria guerreronis,
inhabits the meristematic tissue of the coconut and has a
high reproductive potential,
hence it is important to assess its impact on coconut yield loss. This article
focuses on
yield loss in terms of copra. Infestation
by A. guerreronis reduced
the weight of copra of highly infested coconuts by
32%. When mite infestation was
low, weight loss was only 7%.
Key words: Aceria guerreronis, weight loss, copra
Veterinary Acarology
Monique F. Mul, Thea G.C.M. van
Niekerk, Berry F.J. Reuvekamp & Rick A. van Emous
E-mail: Monique.Mul@wur.nl
p. 513
In 2005 a questionnaire has
been sent to 1,390 Dutch poultry farmers to investigate the severity of the
poultry red
mite (PRM) as a pest problem
in The Netherlands. The response rate amounted to 31%. As the questions were
not
independent of each other,
four clusters of questions were formed, based on two observed, discrete
variables: (1)
directly visible PRM
infestation, and (2) indirect signs of the presence of PRM. Respondents were
distributed over the
most common housing systems in
The Netherlands and reflected the Dutch situation with regards to housing of
laying
hens quite well. More than 80%
of the poultry farmers reported infestations of PRM. Chicken flocks without PRM
problems were significantly
younger than flocks where (signs of) PRM infestation were observed. Where
poultry was
housed in battery cages, more
farmers reported problems with PRM infestations, they tend to apply the first
control
treatment earlier, and repeat
it more often than farmers with poultry in other housing systems. When PRM or
signs
of PRM were reported, farmers
more often applied a combination of control treatments. The mean costs paid for
control
treatments and the costs
incurred in terms of production losses were estimated to be € 0.43 per hen in
an average
flock. Given that there are
300 million layer hens in Dutch poultry houses and that ca. 85% of the flocks
are PRMinfested,
the overall annual cost to the
national poultry industry is estimated at € 11 million. Since the answers to
the
questionnaire revealed a
significant underuse of several measures that could prevent PRM infestation,
there is room
for improvement by more
stringent management.
Key words: Dermanyssus gallinae, poultry red mite, laying
hens, poultry farms, The Netherlands
88 A bioassay to assess the activity of repellent
substances on Ixodes ricinus nymphs
Francesco
Nazzi, Norberto Milani & Igor Saccon
Dipartimento di Biologia e
Protezione delle Piante, Università di Udine, via delle Scienze 208, 33100
E-mail:
francesco.nazzi@uniud.it
p. 517
A simple laboratory assay was
developed to evaluate substances and extracts for their repellent effect on the
tick
Ixodes ricinus L. The bioassay involved
testing the locomotory activity of
stimulus to be tested was
applied onto the arena outside a circle line (4 cm diameter). One
field-collected
nymph was placed in the centre
of the arena and the time spent before entering the treated area was compared
with
that recorded in suitable
control experiments where no stimulus or the solvent alone was used. Apart from
a DEETbased
product that was used as a
positive control, extracts of basil leaves (Ocimum basilicum L.) and leaves of various
grasses were tested. The
commercial DEET-product proved to be active and so was an acetone extract of
basil leaves;
the hexane extract of basil
leaves and the acetone extract from leaves of mixed grasses had very little or
no activity.
The bioassay appeared to be
suitable to assess the repellent activity of natural products. Basil seems to
contain substances
that are repellent to
Key words: Bioassay, Ixodes ricinus, Ocimum basilicum, repellents, sheep tick,
sweet basil
Claire
Valiente Moro, Philippe Fravalo1, Michel Amelot2, Claude
Chauve, Gilles Salvat1 & Lionel Zenner
UMR 958 ENVL/INRA Protozoaires
Entéricoles et Parasites des Volailles, Ecole Nationale Vétérinaire de Lyon, 1,
Avenue
Bourgelat, 69280 Marcy
l’Etoile,
Porcins, Agence Française pour
la Sécurité Sanitaire des Aliments, Zoopole, BP 53, 22440
d’Elevage et d'Expérimentation
en Pathologie Aviaire, AFSSA, Zoopole, BP 53, 22440
p. 521
Dermanyssus gallinae is the most important and
common ectoparasite of laying hens in
being a vector of pathogens. Salmonellosis
is a major sanitary problem in poultry farms. We performed an in vitro
experiment to evaluate the
role of D. gallinae as
a vector of Salmonella enterica serotype Enteritidis (SE). Two ways
of infection of the mites were
tested: through the blood meal by artificially engorging mites on contaminated
blood,
and after cuticular contact by
leaving mites on a bacterial coating. The results showed that the mites could
be infected
via both infection routes. Bacterial
multiplication within the mites has also been demonstrated, as well as the
transstadial
passage of Salmonella from the protonymph to the
deutonymph stage, and the transovarial passage associated
with a negative effect of SE
on Dermanyssus oviposition.
Mites have been shown to retransmit bacteria through a
blood meal. In order to check
whether the ingestion of previously contaminated mites by chicks led to an
infection
dose sufficient to contaminate
birds, sets of 10 mites were orally administered to 1-day-old chicks. Each bird
was
found to be positive 12 days
post-inoculation. Salmonella colonized
the intestinal tracts and invaded liver, spleen, and
caeca. Therefore, this study
demonstrated experimentally that D. gallinae is a vector of SE. The mite may represent a
suitable environment for the
development of Salmonella and
could be an additional factor for the persistence of
Salmonella infection between two flocks. This
underscores the importance of effective red mite control during the
down time following a batch of
poultry infected by Salmonella.
Key words: Dermanyssus gallinae, Salmonella transmission, vector, chicks,
organ colonization, poultry
D.
Sassera, T. Beninati1, S. Epis, C. Bandi, L. Beati2, M.
Montagna, M. Alba, C. Genchi, L. Sacchi3 & N.
Lo1
DIPAV, Sezione di Patologia
Generale e Parassitologia,
of Biological Sciences,
University,
p. 527
Intracellular bacteria are
widespread in nature and may adopt a wide array of life styles. They can be
found free in the
cytoplasm of their host cells,
within host-derived vacuoles, or even in the nucleus. Here, we review current
knowledge
about ‘Candidatus Midichloria mitochondrii’, an
intracellular bacterium that invades the host mitochondria in the ixodid
tick Ixodes ricinus. This bacterium was first
detected by electron microscopy in two independent studies, published
in, 1979 and, 1992, that
showed it in the cells of the ovary in adult ticks and also in the cells of the
ovarian primordia
in larvae and nymphs. This
symbiont resides not only in the cytoplasm, but also inside the mitochondria of
the ovarian
cells, where it appears to
penetrate the outer mitochondrial membrane and colonize the intermembrane
space.
Molecular studies have
recently been performed, addressing the phylogenetic position, transmission,
and prevalence
of this novel bacterium. The
functional significance of this symbiotic association has yet to be revealed. Even
though
‘Candidatus M. mitochondrii’ seems to
behave as a ‘predator’ towards the host mitochondria, this does not appear
to interfere with egg
development, thus ensuring the vertical transmission of the bacteria to the
progeny. The 100%
prevalence in the ovaries of
females of
localization suggests that ‘Candidatus M. mitochondrii’ might be
exploiting the energy available in the
mitochondrial environment. The
possibility that the bacterium is a reproductive parasite should also be
considered.
Key words: Intracellular bacteria,
vertical transmission, mutualism, reproductive parasite, Rickettsiales
Edward
I. Korenberg, Valentina V. Nefedova, Yurii V. Kovalevskii & Nataliya B.
Gorelova
Gamaleya Research Institute
for Epidemiology and Microbiology,
Street,
p. 533
Four hundred adult unfed taiga
ticks (Ixodes persulcatus)
collected in the Cisural region,
means of PCR with primers
specific for the DNA sequences of disease agents pathogenic for humans: Borrelia afzelii,
B. garinii, Ehrlichia muris, Anaplasma pagocytophilum, Babesia microti, and Rickettsia spp. Only the DNA of B. microti
was never found, DNA of at
least one of the other agents was detected in 326 ticks (81.5%), 166 ticks
(41.5%) contained
DNA of two or more agents (17
variants of mixed infections were revealed), and five ticks (1.3%) proved to
contain
DNA of four or five agents. These
results confirm that, as a rule, antagonistic relationships between disease
agents
do not take place in the tick
body.
Key words: Taiga tick, vector, Borrelia, Ehrlichia, Anaplasma, Babesia
92 Seasonality of Megninia
ginglymura: a one-year study in a hen farm in
M.T.
Quintero, M. Itza*, G. Juarez & A. Eleno
Laboratorio de Entomología,
Departamento de Parasitología, Facultad de Medicina Veterinaria y Zootecnia,
Universidad
Nacional Autónoma de México,
CP 04510, México, DF. E-mail: octq1010@yahoo.com.mx; and *Private farmer in
p. 537
Mites of the genus Megninia are known to occur in
different states. In
from feather loss and skin
lesions in several hen farms. To determine the development of these mites
during the year,
samples were collected each
month, from January until December 2005, in hen farms near
samples were taken from five
hens, taking feathers from various anatomical regions, such as head, dorsum,
legs,
wings, vent, anterior face of
thigh, and pectoral zone. The samples were transported to the laboratory, where
mites
were mounted on slides
employing Hoyer’s liquid. All developmental phases – larvae, protonymph,
tritonymph, and
adult (female and male) – were
identified and counted. A total of 2,461 mites were observed: 58.7% adult
(41.4%
females, 17.3% males), 12.3%
tritonymh, 12.0% protonymph, and 16.7% larva. Two peaks of population
development
of M. ginglymura occurred, one in July and the other in
November. These peaks suggest seasonality, with two biological
cycles per year. Megninia is present all year long,
although at a lower population density in March and October.
Therefore, we propose to
combat M. ginglymura in
June and early November, i.e., 1 month before they become abundant.
Key words: Poultry pest, population
dynamics, feather mites, Analgidae
Acaricides
S.R.
El-Zemity1, H.A. Rezk2, Saher Farok2 & A.A. Zaitoon2
1Pesticide Chemistry
Department, and 2Economic Entomology
Department, Faculty of Agriculture,
p. 541
The acaricidal activity of 14
essential oils and 14 of their major monoterpenoids were tested against the
house dust
mite Dermatophagoides pteronyssinus. Mites were exposed for 24
and 48 h to five concentrations of each constituent,
under laboratory conditions.
In general, the acaricidal effect of both essential oils and monoterpenoids
against the
dust mites was time-dependent:
LC50 values decreased with
increasing exposure time. Essential oils from clove, matrecary,
chenopodium, rosemary,
eucalyptus, and caraway oils had high activity. The monoterpenoids
cinnamaldehyde
and chlorothymol were most
effective, followed by citronellol. This study suggests the use of several essential
oils and
their major constituents as
eco-friendly biodegradable agents for the control of the house dust mite, D. pteronyssinus.
Key words: Natural acaricides,
essential oils, monoterpenoids, house dust mite, Dermatophagoides pteronyssinus
94 A gel formulation of formic acid for control of Varroa destructor
Fidel
Avila-Ramos, Gabriel Otero-Colina*, Hussein Sánchez-Arroyo, María Teresa
Santillán-
Alberto
Tecante1
Colegio de Postgraduados
Campus Montecillo; Km 36.5 Carr.
*E-mail: gotero@colpos.mx; and
1Departamento de Alimentos y
Biotecnología, Facultad de Química ‘E’, UNAM, Cd.
Universitaria, D.F., 04510,
México
p. 545
Two formulations of a
starch-based gel containing 85% formic acid were evaluated to control Varroa destructor in bee
hives. Gels were poured in
polyethylene-wrapped plates provided with release areas from 10 to 300 cm2 to regulate
evaporation. In a laboratory
test, at 32 °C and 40-60% r.h., evaporation rate of the plates, expressed as
weight loss,
was determined over 45 days. A
selected formulation and release areas of 16, 32, and 64 cm2, allowing evaporation
of about 10 g per day, were
used in field tests. In June and July 2004, plates were placed inside honey bee
(Apis mellifera)
hives in Tlalmanalco (State of
measured together with their
effectiveness in V. destructor control
and their possible effects on adult and brood population,
presence and activity of the
queen bee, and quantity of food supplies. Mean daily evaporation of formic acid
ranged from 8 to 12 g in both
locations. None of the treatments had negative effects on bee population and
food supplies,
but three queens were lost,
apparently due to excessive handling. Mean effectiveness in reducing the Varroa
population was about 73%.
Treatment with formic acid in a gel formulation is considered to be
economically sound
and practically feasible.
Key words: Formic acid, methanoic acid,
Apis mellifera, bees, honey
Acarological Tools
95 Effect of eight storage
modes on DNA preservation
Matthew
Corriveau, Kaitlin Uppstrom & Hans Klompen1
Undergraduate Biology Program,
and 1Acarology Collection,
p. 553
Proper storage procedures are
essential for specimens that are to be used for future molecular studies. We
tested the
performance of eight storage
modes for specimens of Balaustium sp.
(Acariformes: Erythraeidae) collected on the
same day and all fixed in 95%
ethanol. In tests after 8 months of storage, all four treatments based on
ethanol generated
good quality DNA, irrespective
of ethanol concentration (75 or 95%) or storage temperature (ambient or -20
°C).
Fixation in ethanol and
continued dry and cold storage performed adequately, but storage in Koenike’s fluid,
clearing
in lactic acid prior to
ethanol storage, and use of a lysis buffer, did not generate adequate DNA.
Key words: Balaustium, Parasitengona, DNA
preservation, PCR
96 Spider Mites Web: A
comprehensive database for the Tetranychidae
Alain
Migeon, Elodie Nouguier & Franck Dorkeld
INRA, UMR CBGP (INRA / IRD /
Cirad / Montpellier SupAgro),
E-mail: migeon@supagro.inra.fr
p. 557
Online databases are becoming
a standard tool to study taxonomy, biodiversity, and ecology. We have developed
a
comprehensive database for the
family Tetranychidae (spider mites). The Tetranychidae is one of the most
important
families of the Acari in terms
of economic impact, because it comprises several agricultural pest species of
major relevance,
such as the cosmopolitan Tetranychus urticae. The aim of the web site is
to gather information on all
described spider mites in the
world. The main goal is to provide a synthetic view of the biodiversity of this
mite family.
1,280 literature references
are included, from 1758 to present. 1,257 species, more than 11,745 host
plants, and
5,380 geographical data are
recorded in 17 tables. The database includes taxonomic data relating the
history of
nomenclature, geographical
distribution, and host plants for all species examined. Three types of query
are available
to retrieve this information:
(1) ‘By Species’ allows to search on species names and synonyms; (2) ‘Advanced’
performs
a cross search including
taxonomical, geographical, and host-plant information; and (3) ‘Bibliography’
allows searching
references combining one, two,
or three authors, and it displays all nomenclatural, host plant, and
geographical
data for the selected
reference.
Key words: Database, geographical
distribution, host-plant, internet, taxonomy