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We studied the distribution of chigger mite species over mammal hosts, attachment sites on the host body, habitats, and seasons in Iran. The study was based on 2155 specimens of 36 chigger species collected from 10 species of Muridae, Cricetidae, and Soricidae across six provinces of northern Iran. A high level of mixed infestation by chiggers was recorded—76% of hosts parasitized by chiggers were infested by more than one (2–8) species. Statistically significant differences in the preference for anterior and posterior parts of the host body were found. Three species—Neotrombicula lubrica, N. delijani, and Cheladonta firdousii—preferred the posterior part of the host body; 12 species were characterized by the occurrence in the anterior part and differed from one another by the frequency of presence in the posterior part. One species, Hirsutiella alpina, was found only in the anterior part of the host body (inside the ears of rodents). The most diverse chigger fauna was on the fringe of Golestan National Park (species richness = 21, Shannon–Wiener index = 2.823). The chigger fauna of the high-mountain localities on the Alborz Range was the least diverse (species richness = 16, Shannon–Wiener index = 2.439). The seasonal aspect of activity was evident for Neotrombicula elegans, which exposed the autumn–winter period of the occurrence on hosts, and N. vernalis, with the winter-spring peak of abundance. [ABSTRACT FROM AUTHOR]

Morphology-based identification of Allothrombium spp., in view of the limited knowledge of intraspecific variation, hinders the recognition of species borders and affects the views on the actual distribution of species. Therefore, identification will benefit from reference to molecular methods. The separate species identity of specimens putatively representing Allothrombium fuliginosum and A. pulvinum, both reported as widely distributed in the Palaearctic region and considered as potential biological control agents, was checked using morphological and molecular analyses. The representatives of various Allothrombium spp. collected in the Palaearctic were included in the analysis in order to ascertain the distance between species. The results of the morphological examination, supported by statistical inference, along with the comparison of COI and/or ITS2 sequences, weaken the hypothesis of synoccurrence of both species in the Palaearctic region. Hence, we hypothesize that A. fuliginosum is widely distributed in the Palaearctic, whereas A. pulvinum should be regarded a Nearctic species. [ABSTRACT FROM AUTHOR]

The ectoparasitic honey bee mite Varroa destructor Anderson & Trueman (Acari: Varroidae) is one of the major concerns for worldwide beekeeping. The use of synthetic pyrethroids for controlling the mite was among the most popular treatments until resistance evolved in the mid 1990’s. In Iran, beekeepers are dealing with the parasite and they also used pyrethroids for controlling the mite for a long time. After the evolution of resistance to pyrethroids, they based mite control mostly on treatments with amitraz, organic acids and several management practices. Here we conducted a comprehensive characterization of V. destructor populations parasitizing Apis mellifera in Iran. We determined the genetic variability of mites collected from 28 localities distributed throughout the country. The haplotype of V. destructor was determined by PCR-RFLP, analyzing a fragment of the mitochondrial cox1 gene. It was found that only the Korean haplotype was present in samples from all localities. DNA fragments from cox1, atp6, cox3 and cytb mitochondrial genes were sequenced and the results showed that all samples were identical to the K1-1 or the K1-2 V. destructor haplotypes. Moreover, as it has been reported that resistance to pyrethroids in V. destructor is associated with mutations at position 925 of the voltage-gated sodium channel, a TaqMan®-based allelic discrimination assay was conducted to genotype the mites collected. The results showed that all the mites tested were homozygous for the wild-type allele and, therefore, susceptible to treatment with pyrethroids. [ABSTRACT FROM AUTHOR]

Determination of attraction and avoidance behavior of predators is important in concomitant use of multiple natural enemies to control a pest. The olfactory response of the predatory mite Phytoseiulus persimilis was studied to odors related to Tetranychus urticae adults infected by Beauveria bassiana DEBI008 in 0, 24, 48 and 72 h intervals, both in absence and in presence of plants. In plant-present experiments, P. persimilis attraction was neither towards adults of T. urticae infected by 0.02 % Tween 80 (as control), nor to the ones infected by B. bassiana for 0 or 24 h, whereas significant attraction towards the control was observed when tested against T. urticae infected by B. bassiana for 48 or 72 h. In absence of plants, P. persimilis displayed significant avoidance of T. urticae infected by B. bassiana for 48 or 72 h, when their alternative option was 0.02 % Tween 80-infected T. urticae adults. These results indicate that P. persimilis can recognize the presence of B. bassiana and that the predator avoids the fungus. This suggests that the two natural enemy species can be used together in biological control programmes. [ABSTRACT FROM AUTHOR]

Allothrombium pulvinum Ewing is a common natural enemy of aphids and some other arthropods. So far, there are no studies that have addressed genetic variation of this predatory mite. We investigated genetic variation of A. pulvinum across its whole known range in Iran. A 410 bp portion of the mitochondrial cytochrome c oxidase subunit I gene (coxI) and 797-802 bp portion of the internal transcribed spacer 2 of rDNA (ITS2) were sequenced for 55 individuals from 11 populations, resulting in 12 and 26 haplotypes, respectively. In the coxI region, haplotype and nucleotide diversities varied among populations from 0.00 to 0.90 and from 0.0000 to 0.0110, respectively. In the ITS2 region they varied from 0.20 to 0.91 and from 0.0006 to 0.0023, respectively. For both gene regions the highest haplotype and nucleotide diversities were detected in population Mahmoud Abad from northern Iran. Statistically significant population differentiation (FST) was detected in most pair-wise population comparisons. The results of population differentiation for both gene regions were generally congruent indicating that A. pulvinum from Iran consists of genetically different populations. This suggests that A. pulvinum comprises at least two geographically distinct populations or even more than one species. This study is an initial step towards understanding genetic variation of A. pulvinum, a taxon for which little molecular information is available. More intensive sampling and analysis of additional DNA regions are necessary for more detailed classification of this taxon. [ABSTRACT FROM AUTHOR]