PERSIAN JOURNAL OF ACAROLOGY
Year:2015 | Volume:4 | Issue:1 |Papers Count:11

A new species, Agistemus manjilicus Khanjani, Hajizadeh & Zarei sp. nov. was collected from olive leaves and litter in olive orchards, Olea europaea L. (Oleaceae) in Manjil vicinity, Guilan province, Iran, is described and illustrated.

In the course of a faunistic survey on oppiid mites in Alborz Province, 29 oppiid mite species (Oribatida: Oppiidae) belonging to 11 genera were identified from soil and litter samples, of which three species and one subspecies are new records for the mite fauna of Iran. For new species records, a brief diagnostic characterization is provided. A key to the subfamilies, genera and subgenera of Alborz Province is given. Moreover, a key to species for genera with more than one species is presented.

Paraphytoseius scleroticus (Gupta & Ray, 1981) known only from the holotype female and having some unique morphological features, was examined and photographed in the Zoological Survey of India, Kolkata, India. Voucher photos included in the present study indicate the presence of setae z2 and z4 on the dorsal shield that are serrated and much longer than in any other known species of the genus Paraphytoseius. Seta S5, unique for representing the cracentis species group Chant & McMurtry, 2003, to which P. scleroticus belongs, is clearly evident lateral to seta Z5. Lyrifissure idm5, not discussed or illustrated by Gupta & Ray (1981), is also present posteromedial to base of seta S5. As type specimens of many mites deteriorate over the years and often no longer show important morphological features, or are not available for study by acarologists, or are lost due to various reasons, taking voucher photos of the important features of type specimens, especially of soft bodied mites, is strongly suggested. These may be placed online for use by the phytoseiid taxonomists. A new genus, Paraphytoevanseius Prasad gen. nov., is described and a key for the identification of different genera of the subtribe Paraphytoseiina, including the new genus, and Paraphytoevanseius arjunae (Sadanandan, 2006)comb. nov. are given.

Adult females of Favognathus orbiculatus (Livshitz) and females, male and protonymph of Neophyllobius astragalusi Khanjani & Ueckermann are redescribed. Also, F. acaciae Dogan & Ayyildiz is reported for the first time from Iran.

A new species of the genus Vittacus, V. veronicae Guo, Sadeghi & Xue sp. nov. is described and illustrated based on females collected from Veronica anagallis-aquatica L. (Plantaginaceae) in Ali Abad-e Katool, Golestan Province of Iran. This is the first report of the genus Vittacus from Iran. A key to the species of Vittacus is provided.

An eriophyoid species from Iran is described and illustrated. It is Acerimina bajgahi sp. nov. that has been found on hybrid of a Rosa species (Rosaceae) from south of Iran, Shiraz. This species is new to science and the genus is new record for Iranian mite fauna. It causes witches' broom of terminal twigs of the host plant. A key to the species of Acerimina of the world is provided. A key to world species of Acerimina is provided.

This study presents the histopathological changes of the skin indicating the hypostome with recurved denticles and the chelae of the chelicerae imbedded in the stratum corneum of the epidermis leading to cavitation in lower layers with extravasation of blood in the area of attachment by the tick mouthparts, shearing of skin tissue, liquifaction of cells, and other cellular changes in the area of the tick bite as indicated by several colored photos. No perivascular, lymphocytic, neutrophilic, eosinophilic, or granulomatous presence was seen in the skin indicating no evidence of acute or chronic inflammatory host reaction due to an early infestation of the host mostly localized to epidermis. No deep dermis or hypodermis was received attached with the tick and, thus, no tissue reaction was observed in these two deeper cutaneous layers. The study is of interest indicating removal of tick carefully from the host as soon as possible to avoid cellular-immunologic complex reaction and formation of granuloma or infection in the skin.

The cave tick, Ornithodoros tholozani is the most important soft tick in central Asia and the Middle East. The populations of this species live in human buildings and animal shelters and are responsible for transmission of relapsing fever in different areas. Residual spraying of pesticides is a common control measure against this species, and vast regions of north west of Iran are sprayed annually with pyrethroids by the local residents. Application of limited range of acaricides and similarity in their mode of actions might contribute to emergenence of resistance, and decline of their efficacy. Thus, this research was conducted to identify the susceptibility level of different populations of this tick to some pesticides in old, well-known foci of relapsing fever. Populations of this tick were collected from animal shelters of Mahneshan, Khodabandeh, Tekab and Bijar districts in north west of Iran during 2012–2013. Adult ticks were exposed to different doses of permethrin, lambdacyhalothrin and carbaryl through topical and residual methods and mortality rate was measured after 24 hours. The bioassay revealed different levels of tolerance to permethrin in various populations of O. tholozani in the study area. The Bijar strain was susceptible and the LD50 and LC50 values for permethrin were 48.38 ng/tick and 96.98 mg/cm2 respectively. Tekab, Khodabandeh and Mahneshan populations were resistant and resistance value in this group was 2. The Bijar strain was also susceptible to lambdacyhalothrin and LD50 value for this compound was 8.37 ng/tick. In spite of the susceptibility to pyrethroids in Bijar strain, there was high resistance level to carbaryl and the LD50 value was 5.45 mg/tick. Since different levels of resistance to permethrin were observed in various populations of O. tholozani, reviewing and refining the control measures against ticks, applying new formulations of acaricide mixtures and monitoring the susceptibility level of acaricides seem necessary in these regions. Moreover, future studies to identify the molecular characteristics of resistance to acaricides and determining the effective acaricide are highly recommended in these areas.

Responses of female predatory mite, Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) with different diet experiences were examined in a Y-tube olfactometer. The odor sources were clean air vs. clean bean leaves, clean air vs. Tetranychus urticae (Koch) (Acari: Tetranychidae) infested bean leaves, and T. urticae infested bean leaves vs. clean bean leaves. Female predatory mites that fed on T. urticae as their previous diet for three generations, preferred clean leaves, spider mite infested leaves and again spider mite infested leaves over the alternative odor sources. When N. californicus was fed on T. urticae plus pollen, a significant movement was recorded towards clean leaves rather than clean air, but no significant preference was observed in two other olfactory experiments. Feeding on pollen alone, thrips first instar alone and thrips first instar plus pollen, the predators did not make a significant preference towards the arms in any of the olfactory experiments. Comparing the mean foraging time and predation rate of N. californicus when their prey (T. urticae) were experienced in a direct contact with Frankliniella occidentalis with predators whose prey had previousely received signals due to thrips (F. occidentalis) presence, we recorded a significantly higher foraging time and consumed prey in the patches where thrips were removed. According to our results, N. californicusis capable of detecting its prey and patches with heterospecific (F.occidentalis) and conspecific predators through its diet-based-understanding of chemical cues. Explanations for the olfactory response and foraging behavior of N. californicusare discussed.

Male competition to fertilize the eggs of females would result in conflicts between the members of one sex and evolution of secondary behavioral and morphological characters. Here, we investigated the effect of previous mating experience, territoriality and age on the male mating combat and precedence in two phytoseiid species; Phytoseiulus persimilis and Neoseiulus californicus. Our results showed that naïve P.persimilismales, which had not experienced mating before the experiment, were mostly the ones who were able to mate with the females first. In N. californicus, previous experience did not have any significant effect on the male behavior. Both naïve and experienced males were able to mate females equally. Territoriality had no significant effect on male mating competition, in eitherP. persimilis, or N. californicus. We suggested that phytoseiid predatory mites might differ in phenotypical mating behaveiors, so that although they actively defended their mating territory, the consequences of their ariation in phenotypical mating strategies led to a non-significant territoriality. The effect of age on male competing behavior was remarkable both in P. persimilis and N. californicus. P. persimilis younger males precede the elders in mating with females while in N. californicus, the older males were the ones who mated with the females first. The effects of female re-mating opportunity, the male phenotypical behavior, and spermatophore storage on male competing behavior are discussed.

The two-spotted spider mite, Tetranychus urticae Koch, is a polyphagous pest that causes considerable damage to field, horticultural and greenhouse crops. Currently, many plant essential oils and their active compounds have received attention because of their lethal effect against arthropod pests such as herbivorous mites. In this study, contact toxicity of three formulated compositions based on synthetic thymol and menthol including menthol 5%, thymol 5%, and a mixture of menthol 5%+thymol 5% tested against eggs and female adults of T. urticae. Adulticidal results showed that menthol 5%+thymol 5% had the lowest LC50 value (656.77 ml/l) 24 hours after the treatment. Likewise, the mixture was highly effective againstT. urticae eggs and had the lowest LC50 value (967.24 ml/l). Although, the LC50 value of menthol 5% and menthol 5%+thymol 5% were not significantly different from each other but both of them had a significant difference with the thymol 5% in manner of adulticide and ovicidal. Results also showed that a combination of thymol and menthol increased lethal effects compared to these two compounds.