Author: (Kessler, 1857)
Neogobius gymnotrachelus (Kessler, 1857)
Status in World Register of Marine Species:
Accepted name: Neogobius gymnotrachelus (Kessler, 1857) (updated 2009-06-25)
Diagnosis: nape naked in midline before level of preopercle; otherwise, scales ctenoid. Head depth at eyes equalling or to 1.25 head width. Inter-orbit about 0.3-0.5 eye diameter. Angle of jaws below anterior quarter of eye. Snout equalling or to 1.2 eye diameter. Upper lip of uniform width, 0.6-0.75 of lateral preorbital area. Pelvic disc 0.9 to equalling abdomen length, anterior membrane without lateral lobes. Caudal peduncle depth between 0.5 and 0.6 own length. Dl VI (V-VII); D2 I + 16 17 (15-18); A I + 13-15 (12-16); P 16-18. Scales in lateral series 56-62 (54-65). Vertebrae 32-33 (32-34). Colour: greyishbrown, with oblique dark bands across sides of body; males darker. Size: to 16 cm.
Habitat: slightly brackish and freshwaters, lower reaches of rivers and coastal lagoons, rarely mesohaline; on sand or mud. Food.:crustacea (especially corophiid amphipods), aquatic insects (mostly chironomid larvae), polychaetes, also small fish and molluscs. Reproduction: April to end of June (Bulgarian waters). Eggs under shells or stones. Sexually mature at 2 years. Hybridization: with N. kessleri (Pinchuk and Strautman, 1977).
Distribution: Black Sea, Sea of Azov, Caspian Sea and tributaries.
Eggs, larvae and young stages. No data.
Otoliths (sagitta). No data.
Subspecies
Neogobius gymnotrachelus gymnotrachelus: Black Sea and Sea of Azov.
Neogobius gymnotrachelus macrophthalmus (Kessler, 1877): scales in lateral series 45-58, D2 I + 15-16, A I + 12-14; Caspian Sea.