Neogobius bathybius ( Kessler, 1877 )

Zarei, Fatah, Esmaeili, Hamid Reza, Abbasi, Keyvan, Kovačić, Marcelo, Schliewen, Ulrich K. & Stepien, Carol A., 2022, Gobies (Teleostei: Gobiidae) of the oldest and deepest Caspian Sea sub-basin: an evidence-based annotated checklist and a key for species identification, Zootaxa 5190 (2), pp. 151-193 : 174

26. Neogobius bathybius ( Kessler, 1877) ( Fig. 21 ), Deepwater Goby

Gobius bathybius, Kessler, 1877: 17 , pl. 1 (fig. 3); type locality: Svinoi Island , south of Baku, Caspian Sea, Azerbaijan, depth 756 feet ; types: type material of Gobius bathybius appears to be missing from the collection of St Petersburg State University .

Etymology: Greek, bathus = deep, refers to capture of the holotype in deep waters.

Distribution and habitat: Present in all three areas of the Caspian Sea ( Fig. 22A ). No records appear to exist from the east coast of the Middle Caspian Sea. A relatively deep water species found under pleio-mesohaline conditions and known from depths to 75 m and may occur deeper (Pinchuk et al. 2004b). Does not enter rivers (Pinchuk et al. 2004b).

Remarks: Formerly in the genus Chasar Vasil’eva, 1996. Neilson & Stepien (2009) included Gobius bathybius in the genus Ponticola because they then lacked access to specimens of bathybius . Molecular data by Zarei et al. (2021) and by Tajbakhsh et al. (2022) have provided support for its reclassification in the genus Neogobius . DNA sequence data analysis by Tajbakhsk et al. (2022) indicated that there is a single population of N. bathybius across the Southern Caspian Sea.

Material examined: ZM-CBSU S063, 3, off Babolsar , & ZM-CBSU S064, 1, off Neka , Mazandaran Province, Iran ; ZM-CBSU A256 - A297 , 36, off Kiashahr , Gilan Province, Iran .

IUCN: LC ( Bogutskaya 2020l).

Figures

FIGURE 21. Neogobius bathybius. ZM-CBSU M2114, off Babolsar, Mazandaran Province, Iran (Zarei et al. 2021).

FIGURE 22. Distribution of (A) Neogobius bathybius, (B) Neogobius caspius, (C) Neogobius melanostomus, and (D) Neogobius pallasi.