Subterranean Fishes of the World

Generic name misspelt Nemachilus by Pereladov (1989).

Country

Types

Holotype: ZISP 46159 49.5mm SL. Paratypes: ZISP 46160 3 specimens 36.7mm, 43.6mm, and 47.6mm SL. ZISP (no reference number) 44.2mm SL. ZMMU P16030 and P16031 56.8mm and 61.0mm SL. This species is the type species by monotypy of the subgenus Troglocobitis.

Distribution

Known only from the type locality: Provull gypsum Cave, 45 km from the railway station at Tcharchanga and 60 km from the town of Gaourdak, in the mountainous area of Kugitangtau, Turkmenistan (c.40^oN, 60^oE). Despite a search of other similar sites in the same area Smirnov (1983) did not find any other locations for this species. Provull Cave is about 5 km SW of the Cupp-Coutunn Cave in a gypsum karst.

Habitat

Collected "in a karst collapse which opened in a region of subterraneous water flow” (Parin 1983), December water temperature 24^oC (Smirnov 1983). The animals live in a lake within a gypsum cave and feed on a bacterial film on the surface of organic silt and/or on insect larvae and small Crustacea. This area is under the roosts of birds and bats. The fishes move about within the lake from depths of 4-5m down to at least 58m (Pereladov 1989). In May the water temperature was 19-20^oC and the females were full of ripe eggs.                                                                                                                                             

Systematics

Sufficiently distinct to merit erection of the subgenus Troglocobitis to contain it. Nalbant and Linares (1987) placed this species in the genus Paracobitis (retaining the subgenus Troglocobitis) but without giving their reasons. This was followed in the review paper of Decu et al. (2019). Eschmeyer's Catalogue of Fishes (Fricke et al. 2019) and the authoritative summary of world Cobitoidei (Kottelat 2012) both retain Troglocobitis and this is followed here.

According to the detailed phylogenetic study of Prokofiev (2010) Troglocobitis is sister genus to Paracobitis and both of these together are sister to Iskandaria Prokofiev 2009. All three genera are inluded in the tribe Nemacheilini within the subfamily Nemacheilinae.

Although the formal description of the species was published by Parin (1983) the name is available from Parin and  Dolzhanskij (1982).

Biological Notes

The food supply in the cave might result from chemoautotrophic production as well as imported from outside.

Museum Holdings

Four other specimens in addition to the type series, probably at IOAS.