Tridentiger trigonocephalus ( Gill, 1859 )

Kovačić, Marcelo, Renoult, Julien P., Pillon, Roberto, Svensen, Rudolf, Bogorodsky, Sergey V., Engin, Semih & Louisy, Patrick, 2022, Identification of Mediterranean marine gobies (Actinopterygii: Gobiidae) of the continental shelf from photographs of in situ individuals, Zootaxa 5144 (1), pp. 1-103 : 87

Tridentiger trigonocephalus ( Gill, 1859) ( Fig. 9 )—Chameleon Goby

Triaenophorus trigonocephalus Gill, 1859: 18 ; type locality: Hong Kong .

Size. Reaches 11 cm total length.

Morphology. D VI + I,11–13; A I,10–12; P 19–20, single uppermost ray free. Body moderately elongate, nearly round anteriorly and laterally compressed posteriorly, depth 5.3–5.8 in standard length. Head large, somewhat depressed, with relatively short blunt snout. Caudal peduncle deep, but lower than body depth. First to fifth spines of first dorsal fin subequal in length, none elongate. Pelvic fins joined to form a disc. Caudal fin rounded, shorter than head ( Boltachev & Karpova 2017). Scales present on body, usually poorly visible on photographs. No scales on head and prepectoral area; predorsal area naked.

Live coloration. Body brown to beige, usually with 2 continuous or interrupted dark brown stripes ( Fig. 9 ), first beginning from just above orbit, continuing along back and ending at upper caudal-fin base, second stripe extending from snout through eye along mid-side of body ending at caudal-fin midbase. Side of head with small pale spots. Another color form with stripes interrupted by pale interspaces, short brown bars on back and the black spot on upper caudal peduncle visible. A third color form is blackish with indistinct stripes.

Similar species. Gobius vittatus .

Habitat. Inhabits sand and stone bottoms in marine and brackish waters at depths of 1–5 m.

Geographic distribution. Native distribution range is confined to Japan, Korea and China. Introduced to eastern Pacific, Australia and Black Sea in the Sevastopol Bay ( Boltachev & Karpova 2017). In the Mediterranean there is a single record from Ashdod, Israel ( Goren et al. 2009).

Figures

FIGURE 9. Live coloration in its natural habitat of Tridentiger trigonocephalus. Photo by Sascha Schulz/iNaturalistAustralasian Fishes Project, Victoria, Australia.