Schaefferia czernovi (Martynova, 1978)

Figs 3, 9, 11

Ceratophysella czernovi Martynova, 1978: 37

Type-locality: Tareya, Taimyr Peninsula, Russia

Material studied. Northeastern Europe: Kolguev Isl. (two specimens); Dolgii Isl. (14 specimens); Bolvanskaya Guba bay (37 specimens); Pakhancheskaya Guba bay (35 specimens); Khaipudyrskaya Guba bay (two specimens); Waigach Island (two specimens); Komi Republic (four specimens); Southern island of Novaya Zemlya Archipelago (56 specimens). Siberia: Yamal Peninsula (seven specimens); Taimyr Peninsula (69 specimens), Putorana Plateau (13 specimens); Yenisei basin, Mirnoe [60° 20’ N] (two specimens). Deposited in the author’s collection.

Remarks. The absence of labial papilla C (Fig. 3) together with almost complete chaetotaxy of A - type permits to identify this species easily. As in S. bermani sp. nov. most of dorsal chaetae in S. czernovi are rather stout due to hyaline “cover” although this character appears to vary in regional populations. Mainly the species’ chaetotaxy is stable, with only the frequent absence of a 1 on one or both sides of Abd.4 (in other specimens these chaetae are widely separated) and the occasional absence of microchaeta p 3 on the same tergum (asymmetrically as a rule) (Fig. 9) observed. There is only one exception to the morphological homogeneity of S. czernovi; that is in several cave populations in Middle Ural Mountains. Most of the adult specimens collected in this region are characterised by the absence of a 2’ chaetae on Abd.1–3 as well as some of m -chaetae on the same terga, chaetae p 3 on Abd.4 is also usually absent. Formally they could be described as a new species because a 2’ chaetae (= m 2 in Thibaud et al. 2004 & Jordana et al. 2012) are present on Abd. 1–3 in all known congeners with 5+5 ocelli. One slightly more intensively coloured specimen (probably inhabiting upper part of the cave), collected at the same date together with several abnormal specimens, has the same chaetotaxy as true northern S. czernovi. Therefore, I prefer to treat this cave form as a part of the same slightly polymorphic species.

Distribution. Jordana et al. (2004) consider S. czernovi as a Siberian species. Current records show that its distributional range covers northeastern part of Europe and north of West and Middle Siberia (Fig. 11). There is also one published record of the species on Chukotka (Babenko et al. 1994; Babenko & Fjellberg, 2006), which appears to be erroneous or at least in need of confirmation but the specimen is currently unavailable.