Ponticola constructor (Nordmann, 1840)

Ponticola constructor View in CoL

Common name. Caucasian goby.

Diagnosis. Distinguished from other species of Ponticola entering freshwater in West Asia by: ○ lateral part of upper lip distinctively swollen / ○ lower jaw strongly prognathous / ○ predorsal area finely mottled / ○ two suborbital transverse rows below suborbital longitudinal row b / ○ first

dorsal without bold, distal dark-brown band / ○ pelvic disc reaching 40–60 % of distance between its origin and anus / ○ 53–74+2–4 scales in midlateral series / ○ pelvic-disc fraenum with angular lobes whose length is 1 ⁄ 6 – 1 ⁄ 2 of fraenum width at base. Size up to 200 mm SL.

Distribution. Black Sea drainages of southern Caucasus from lower Çoruh ( Türkiye) north to Noworossiysk ( Russia). Also, in western tributaries of Kuban.

Habitat. Cold mountain to warm foothill streams. Not found in brackish water.

Biology. Matures with 1–2 years and spawns in May–June. Nuptial male almost entirely black. Several females may spawn with one male, and female are expected to spawn several times during season. Male guard eggs and larvae in gravel or rocky burrows. Feeds on a wide range of small invertebrates and fish.

Ponticola constructor ; Kuban drainage, Russia; ~ 85 mm SL.

Conservation status. LC.

Remarks. Ponticola rhodioni is treated as a synonym. It has been described based on chromosomal characters only, and morphological or molecular characters do not support P. rhodioni as a valid species. Molecular characters distinguish P. constructor well from P. rizensis and P. turani , and published morphological data places P. constructor intermediate between these two species. However, all characters used to

Ponticola cyrius ; Kura drainage, Türkiye; ~ 80 mm SL. © M. Özuluğ.

distinguish P. constructor , P. rizensis , and P. turani largely overlap in fresh material we examined, and further studies are needed to distinguish at least the two species supported by molecular characters ( P. constructor and P. rizensis ).

Further reading. Berg 1949b (description as N. cephalarges constructor , in part); Vasil’eva & Vasil’ev 1994 (description); Vasil’eva & Vasil’ev 2003b (distribution, description, biology).