A new species of Olopachys Berlese (Acari: Pachylaelapidae) from Iran with a key to the world species

A new species, Olopachys iraniensis n. sp. (Mesostigmata: Pachylaelapidae) is described based on adult females collected from soil in Guilan Province, northern Iran. Two identification keys are provided, one for all known species of Olopachys, and the other for species recorded from Iran. A brief review on pachylaelapid mites of Iran is also provided.


Materials and methods
Mite specimens were collected from soil under poplar and pine trees in Guilan Province, forest areas of the Emamzadeh Hashem in Rasht County and soil under citrus trees in Langrud County. After extraction using Berlese-Tullgren funnels, the mites were removed under a stereomicroscope, preserved in 75% ethanol, cleared in Nesbitt's fluid and then mounted on microscope slides in Hoyer's medium. Morphological observations, measurements, and illustrations were made using a compound microscope equipped with differential interference contrast and phase contrast optical systems, and a drawing tube. Photos were taken using a Canon Camera DS126311, attached to the microscope. Measurements are given in micrometers (μm); each measurement corresponds to the average followed (in parentheses) by the respective ranges. Lengths of dorsal, sternal, and genitiventrianal shields were measured from the anterior to posterior margins along their midlines. Maximum widths of dorsal and genitiventrianal shields were taken at their widest points. Width of sternal shield was measured at the mid-level of coxae II. Lengths of dorsal setae were measured from bases of their insertions to their tips. Terminology for dorsal and ventral idiosomal chaetotaxy used in this paper follows that of Lindquist and Evans (1965). Identification of pore-like structures on the idiosomal integument is based on the morphological observations of Athias-Henriot (1969); notation for these structures such as adenotaxy and poroidotaxy follows Johnston and Moraza (1991) and Moraza and Pena (2005). Leg setal notation and chaetotactic formulae are based on Evans (1963). Holotype and two female paratypes of the new species are deposited in the Acarology Laboratory, Department of Plant Protection, Faculty of Agricultural Sciences, University of Guilan, Iran. One paratype female will be deposited in the Acarological Collection, Jalal Afshar Zoological Museum, Department of Plant Protection, Faculty of Agriculture, University of Tehran, Karaj, Iran. The checklist of Pachylaelapidae of Iran is arranged alphabetically according to genera. For each species, only the first record of the species in the literature, for Iran, is cited; further reports of the same species are not mentioned in the checklist.
Spermathecal apparatus (Fig. 3B) -Sperm access system associated with coxae IV. Tubes of sperm induction system hyaline, well-developed, stout and slightly curved (somehow comma-shaped) with thin ductus inside.

Male. Not found.
Etymology -The specific name of the new species refers to Iran, the country where the type specimens were collected.

Key to world species of the subgenus Olopachys (Olopachys) (females)
The key to the world species of the subgenus Olopachys (Olopachys) presented by Özbek (2016) is modified here to accommodate the new species from Iran. The specimens of Olopachys  iraniensis n. sp., O. compositus Koroleva, 1976 andO caucasicus Koroleva, 1976 were examined, characteristics of other species were obtained from literature.  Koroleva, 1976 Key to species (females) of the genus Olopachys Berlese occurring in Iran 1. Tubes of sperm access system quite long, spiralled apically ( Figure 4A) . . . . . O. compositus Koroleva, 1976 -Tubes of sperm access system short ( Figure 4B) or normal in length, straight or moderately curved apically ( Figure 3B, 4C

Remarks on Pachylaelapidae of Iran
The fauna of Pachylaelapidae in Iran is poorly known. So far, 25 species of pachylaelapid mites from four genera are known from Iran (20 species recorded and five species described). The complete identification of mites of the family Pachylaelapidae in Iran requires additional studies in the future. Tabulated checklist of Iranian pachylaelapid mite species based on their genera is as follow (Table 1).