Hypogastruridae, Borner, 1906

Antipova, M. D. & Babenko, A. B., 2022, An annotated checklist of the springtails (Hexapoda: Collembola) recorded from the foothill and mountain parts of the Republic of North Ossetia-Alania, North Caucasus, Russia, Russian Entomological Journal 31 (4), pp. 331-345 : 335-336

Family Hypogastruridae

** Hypogastrura assimilis (Krausbauer, 1898) . This subcosmopolitan species has been recorded from the republic (winter collections in the floodplain of Ardon River in the outskirts of Alagir, O.L. Makarova) for the first time.

H. hohi Babenko, 1994 . The Caucasian endemic, known only from the type locality in North Ossetia: basin of the Ardon River, Rocky Ridge , western spurs of Mt. Karyuhokh at 2800 m a.s.l. The species was described based on material of I.T. Kuchiev.

H. manubrialis (Tullberg, 1869) . Cosmopolitan (?), often occurring in composts. In North Ossetia, it was recorded within the Alaniya National Park (upper reaches of the Karaugom River near the glacier) [Stach, 1949] and in a pasture east of Alagir [ Kremenitsa, 2002, as sp.gr.].

H. socialis (Uzel, 1891) . A species currently considered to be Palaearctic [ Fjellberg, 1998], although its easternmost records are restricted to the southern Urals [ Buinova et al., 1963; Stebaeva, 1976]. In North Ossetia (floodplain of the Ardon River, vicinity of Alagir, winter collections by O.L. Makarova), the species has been found for the first time.

H. tepli Skarżyński et Babenko, 2010 . Endemic to the Caucasus, belonging to the crassaegranulata -group, described based on collections of I.T. Kuchiev from a protected area of the nature reserve (Kurtat Gorge, 3410 m a.s.l.). In the springtail list of the reserve [ Kuchiev, 2006], the species is erroneously listed as H. ossetica Babenko (nomen nudum). No records outside the type locality are known.

H. vernalis (Carl, 1901) . A Palaearctic species distribut- ed almost throughout Russia [ Babenko, 1994]. In the nature reserve, the species is common in low-mountain broad-leaved forests, and in spring it can form large aggregations in damp places [ Kuchiev, 2006]. We have found only one adult individual in a developed birch forest at an altitude of 2244 m above sea level.

Ceratophysella alani ( Babenko, 1994) . A Caucasian endemic, known only from the type locality: Tsey Gorge, moraine of the Skazsky glacier, 2100 m a.s.l. [ Kuchiev, 2006, as species of the genus Hypogastrura ]. Initially, the species was assigned to the subgenus Mitchellania Wray, 1953 , which included a rather clear group of species occurring in eastern Asia and North America. Ceratophysella alani is the only species of this group with such a western distribution. Despite the currently accepted synonymy of Mitchellania and Ceratophysella [see Skarżyński and Christiansen, 2008], the species occupies a quite distinct position among the European congeners.

C. caucasica Martynova, 1964 . This was originally described from Abkhazia. Apparently, it is widespread not only in Transcaucasia, but also in the North Caucasus, in particular at Teberda [Dobrolyubova, 1984, 1984a]. In the territory of the nature reserve, it was recorded by N.A. Kuznetsova et al. [2019] from pine forests near Verkhniy Tsey and Nar. Unfortunately, the species could not be found in the relevant material of these authors. This is also absent from our collections from the higher elevations of Tsey.

C. denticulata (Bagnall, 1941) . A Holarctic or even cosmopolitan species, possibly due to introduction. In our material from the nature reserve, only a single specimen has been found at an altitude of 2295 above sea level.

C. sp. aff. succinea (Gisin, 1949) . Probably a new species differing from C. succinea by the small size and a complete set of labial papillae. In the upper reaches of Tsey River, it inhabits a wide range of biotopes: from bare ground around the glacier to forest ecosystems of different age. In the paper of N.A. Kuznetsova et al. [2019], it was this species, record- ed from the vicinity of Verkhniy Tsey and Nar, that was referred to as Ceratophysella sp. Based on available data, the species also occurs in other regions of the North Caucasus (e.g., in our collections from the vicinity of Mount Elbrus). Possibly some old records of C. succinea from the highlands of the Western Caucasus [ Petrova and Dobrolyubova, 1987; Dobrolyubova, 1988, 1995] also belong to this species. There is only one record of C. succinea from the lowlands of North Ossetia [ Kremenitsa, 2002], but considering all above evidence, the species identity requires verification.

There are also a number of unidentified records of the genus, but it is very difficult to judge about their species identity [ Kuchiev, 1984, Kuchiev, 2006 referred to as C. armata ; Kuznetsova et al. 2019].

Orogastrura parva (Gisin, 1949) . The species was listed as a common inhabitant of the forest belt of the nature reserve [ Kuchiev, 2006, as a member of Hypogastrura ]. From our point of view, the occurrence of this species, previously known only from the Alps, Apennines, Sudetes and Carpathians [ Skarzynski, 2011; Thibaud et al., 2004], in the Caucasus needs to be confirmed.

Choreutinula inermis (Tullberg, 1871) . A widespread species also recorded from the Caucasus [Dobrolyubova, 1984, 1984a; Petrova and Dobrolyubova, 1997]. According to the list of the springtails [ Kuchiev, 2006], this species is rare in the nature reserve and inhabits the litter of pine forests of Tsey Gorge.

** Schoettella ununguiculata (Tullberg, 1869) . A Holarctic species. The only available record from South America is considered doubtful [ Mari Mutt and Bellinger, 1990]. In the Tsey Gorge, it has been collected from the bark of a maple forest located at the confluence of Medik and Tsey rivers, at 1865 m a.s.l. Previously, this species has not been recorded from the republic.

Xenylla osetica Stebaeva et Potapov, 1994 . A Caucasian endemic, known only from the type locality: vicinity of the village of Zintsar (collections of I.T. Kuchiev).

** X. szeptyckii Skarżyński, Piwnik et Porco, 2018 . One of the species of the maritima -group recently revised and reliably known from Poland, Slovakia, Hungary, France and Sweden. Given the rather wide distribution of the preferred habitats (mosses and lichens on rocks, dry sandy soils, forest litter, anthills, bird nests, mountainous and flat areas) and the tendency to synanthropy, it can prove to be much more widespread. The species has been discovered in the nature reserve for the first time (Tseydon Valley, a mature pine forest with a thick moss cover), but most likely this very species was previously recorded from the forest belt of this nature reserve and referred to as X. maritima [ Kuchiev, 2006].

Typhlogastrura preobrazhenskyi Babenko, 1987 . A Caucasian endemic and troglobiont [ Kuchiev, 2006], described from the Shubi-Nykhasskaya Cave in the Alagir Gorge (corpses of Myotis blythii , about 150–200 m from the entrance).

Willemia anophthalma Börner, 1901 . A Holarctic species, common in taiga and southern tundra regions, rarely found beyond. In the nature reserve, the species clearly prefers developed forests [ Kuchiev, 2006; Kuznetsova et al., 2019].

W. denisi Mills, 1932 . One of the most common Holarctic species occurring in coniferous litter in the taiga zone. Only one individual was recorded from the nature reserve [ Kuznetsova et al., 2019]. In the higher part of Tsey Valley, it has not been revealed.

** W. intermedia Mills, 1934 . Holarctic. Previously, the species has not been recorded from North Ossetia. We have found it in the Tsey Gorge at an altitude of 2250 m a.s.l. in a young mixed forest.

W. scandinavica Stach, 1949 . Holarctic. From the nature reserve, it was recorded so far only from pine forests in the vicinity of Verkhniy Tsey [ Kuznetsova et al., 2019].