New data on some Antennoseius Berlese species (Acari: Ascidae) from Russia

This paper reports on four species of the genus Antennoseius Berlese phoretic on ground beetles (Coleoptera: Carabidae) from Russia: Antennoseius (Vitzthumia) bregetovae Chelebiev; Antennoseius (Antennoseius) bullitus Karg; A. (A.) pannonicus Willmann and A. (A.) ponticus Trach and Makarova. Moreover, we provides additional morphological information and new illustrations for two species of Antennoseius Berlese – A. (V.) hyperboreus Nikolsky and A. (V.) koroljevae Chelebiev based on the type series to facilitate species delimitation.


Introduction
A remarkable diversity of phoretic and parasitic mites is found on ground beetles, representing three major groups: the Mesostigmata, Prostigmata, and Astigmatina (Olynyk and Freitag 1979; Hunter and Rosario 1988; Felska et al. 2018. Deutonymphs and adults of many families of Mesostigmata have established close phoretic relationships with ground beetles, and phoresy by adult females is common phenomenon among two genera of family Ascidae -Antennoseius Berlese and Anystipalpus Berlese (Lindquist et al. 2009; Trach 2013. Antennoseius is well known as a group of predatory mites generally found in soil, litter, moss in meadow, and forests, as well as in nests of rodents and birds but many species are also recorded on carabid beetles as phoretic (Ryke 1962; Costa 1969; Bregetova 1977; Karg 1993; Halliday et al. 1998; Eidelberg 2000; Beaulieu et al. 2008; Trach and Makarova 2008; Lindquist and Moraza 2009; Trach 2013; Moraza and Kazemi 2009; Kazemi and Moraza 2013; Faraji et al. 2017; Kazemi 2018. The genus comprises about 58 nominal species that are recorded worldwide (Moraes et al. 2016; Kazemi 2018; Bahrami and Kazemi 2019. Of these species, about 23 species of Antennoseius are phoretic on ground beetles (Faraji et al. 2017). Before this study, only five species regarded to belong to Antennoseius had been reported phoretic on ground beetles from Russia (Bregetova 1977; Faraji et

Material and methods
This study is based on phoretic Antennoseius species on ground beetles that were collected during several biological expeditions in Russia over a period of two years (2020)(2021) and also on examination of type series of some specimens deposited in the collection of the Institute of Systematics and ecology of animals (ISEA, Novosibirsk), and collection of the Zoological Institute of the Russian Academy of Sciences (ZIN, Saint Petersburg). Host beetles were collected from different habitats by individual hand picking and placed individually in vials with 96% ethanol. Alcohol sediments from the vials were inspected for phoretic mites. Mites were removed from the beetles and alcohol sediments, cleared in lactic acid solution and mounted in Hoyer's medium . The line drawings and examinations of the specimens were performed with Zeiss Axio Imager A2 and Leica DM 2500 compound microscopes equipped with drawing tubes and differential interference contrast and phase contrast optical systems, attached to cameras AxioCam ICc 5 and ICC50 HD, respectively. Most images were captured in stacks (with focal depth manually controlled). Selected images were combined using Helicon Focus 7.6.4 Pro (Helicon Soft Ltd., 2000). Digital drawings were prepared using Adobe Photoshop CS2 software based on the original pencil line drawings. Images and morphological measurements were taken via ZEN 2012 software (version 8.0) and Leica Application Suite (LAS) software (version 4.2, Live and Interactive Measurements modules). Photomicrographs were taken with an AxioCam 506 camera (Carl Zeiss, Germany). Measurements of structures are expressed as ranges (minimum-maximum) in micrometres (μm). Podonotal and opisthonotal shields length were taken from anterior to posterior margins as midline and their width, respectively, from lateral margins at the level of dorsal setae r2 and at level of setae S1. Length and width of sternal shield measured at midline and level of st2, respectively. The length of the genital shield was measured along the midline from the anterior margin of the hyaline extension to the posterior margin of the shield, and its width where maximal (at level of setae st5). Anal shield was measured on midline length from anterior to posterior margins including cribrum and its width at the broadest point. Leg length was measured from the base of the coxa to the apex of the tarsus (excluding the pre-tarsus). The nomenclature used for the dorsal idiosomal chaetotaxy follows that of Lindquist and Evans (1965), the notations for leg and palp setae follow those of Evans (1963a, b), and other anatomical structures mostly follow Evans and Till (1979). Notations for idiosomal pore-like structures (gland pores and poroids/lyrifissures) and peritrematal shield follow mostly Athias-Henriot (1971, 1975. The notations for pore-like structures on the sternal shield and for the peritrematal shield region also follow modifications and additions by Johnston and Moraza (1991).
Remarks -Antennoseius (V.) bregetovae was described from Kazakhstan (Chelebiev 1984). It has been found in nest of steppe vole, Lagurus lagurus (Pallas) (Rodentia: Cricetidae). The description of this species is brief and both the description and illustrations lack many important details. Since that time, there has been no other formal occurrence or recording of this species in the world, and is now recorded in Russia for the first time, on ground beetle Harpalus sp. (Coleoptera: Carabidae). Lindquist and Moraza (2009) suspected this species to be a senior synonym of Antennoseius (Vitzthumia) koroljevae Chelebiev due to both smoothmorph (phoretic) and granular-morph (free-living) occurred in the same locality and habitat, were discussed by Lindquist and Walter (1989). But according to Chelebiev (1984) and our observations on labels of type series of both species, these two species have been collected from two different nest of Rodents in two different regions and habitats (see provided information in specimens examined section for both species in the current study). In the meantime, A. (V.) koroljevae was collected about two years after A. (V.) bregetovae. Therefore, we believe these are two distinct species. The diagnosis given above is based primarily on specimens from Russia, but also in comparison with the type material. The species is easily recognized by the podonotal shield with four pairs of spur-like setae (j3-5 and z4), both setae of coxa I and posterior seta of coxa II modified as spines (pointed abruptly at tip), and leg I with setae pd of trochanter and pd2 of femur stout, pointed, spinelike, and with pd3 of genu stout, spinelike, blunt.
Remarks -Antennoseius (V.) hyperboreus was described from tundra in Northern Russia (Nikolsky 1988). It has been found on tundra vole, Microtus oeconomus (Pallas) (Rodentia: Cricetidae). Since that time, there has been no other formal occurrence or recording of A. (V.) hyperboreus in the world. The original description of the species is brief and its illustrations are incomplete, lacking many important details. We herein redescribe A. (V.) hyperboreus on the basis of type series to complement the original description which provided by Nikolsky (1988). The species is easily recognized by the podonotal shield with 20 pairs of setae, none of the setae enlarged (in distinction from others), setae j1 and Z5 sparsely barbed and slightly thicker than other setae, sternal shield with strong anterior medial notch (reaching to level of iv1), lateral soft cuticle with 35-36 pairs of setae (including ventral setae), coxal setae on legs I-IV slender and setiform, four long subapical setae on tarsus I (ratio of subapical setae / tarsus I length ≈ 0.65).
Remarks -Antennoseius (A.) ponticus was originally described from southern Ukraine (Odessa and Mykolaiv Regions) where it was found on carabids (Harpalus serripes (Quensel), Amara sp.) and leaf beetle, Chrysolina gypsophilae (Küster) (Coleoptera: Chrysomelidae) (Trach and Makarova 2008), and afterward has been recorded from Eastern Ukrain (Trach 2013). It is now recorded in Russia for the first time, on Harpalus sp. (Coleoptera: Carabidae). Our specimens agree very well with the description given by Trach and Makarova 2008. The species may be recognized primarily by the podonotal shield with five pairs of spinelike (with a short thin tip) setae (including z4) ( Figure 9A), presternal region with one pair of oblique narrow distinct platelets ( Figure 9B), ventral posterior seta on coxae I and II modified as spines, pointed abruptly at tip ( Figure 9B), fixed digit of chelicera with six teeth and movable digit with two large teeth medially and a minute tooth subapically ( Figure 9D). The illustration and descriptions of the hypostomal groove in Trach and Makarova's (2008) shows six transverse rows of denticles, each row with 6-7 small denticles. Based on the specimens collected in Crimea, we found hypostomal groove with seven transverse rows of denticles, with smooth anterior and posterior transverse lines, rows 1-6 each bearing 2-4 small denticles, 7 th row with only one median denticle ( Figure 9C).