Cottus nikolskii Berg, 1900

Sideleva, Valentina G. & Zhidkov, Zakhar V., 2021, An annotated type catalogue of freshwater sculpins (Cottoidei) described by Lev Berg, Zootaxa 5016 (2), pp. 229-242 : 238

Cottus nikolskii Berg, 1900

( Fig. 11 )

Holotype: ZIN 11676, Lake Baikal , delta of Selenga River, depth 220 m, 1898, collector of the East Siberian Department of the Imperial Russian Geographical Society.

Current status: Batrachocottus nikolskii ( Berg, 1900) ( Berg, 1949; Taliev, 1955; Sideleva, 2003).

Counts: D1 6, D2 16, A 12, P 15, V 4, C 23, vert. 36 (abdominal 12, caudal 24), two-pairs of pleural ribs.

Diagnosis: head is rounded in front, length of head is comparable to its width; very large pores of lateral line on head; lateral sensory canal short, has 11 pores; first dorsal fin narrow, its ray length two times shorter than that ray length of second dorsal fin; spines on preoperculum are absent; color of trunk is light pink and creamy.

Proportional measurements as percentages of standard length (193.4 mm): predorsal length 38.3, preanal length 55.7, maximum body depth 13.0, length of caudal peduncle 19.0, depth of caudal peduncle 6.0, length of first dorsal-fin base 12.9, length of second dorsal-fin base 29.3, length of longest anal-fin base 23.6, length of longest first dorsal-fin ray 4.0, length of longest second dorsal-fin ray 13.2, length of longest anal-fin ray 11.4, pectoral-fin length 17.3, pelvic-fin length 10.4, distance between first and second dorsal fins 8.8, head length 31.4, postorbital length 16.5, head depth 16.1, head width 29.3, eye horizontal diameter 5.1, snout length 10.3, interorbital width 8.4, upper jaw length 14.2, interbranchial width 5.2, length of gill slit 18.5.

Figures

FIGURE 11. Cottus nikolskii Berg, 1900 ZIN 11676, holotype, photo (A) and radiograph (B).