castaneus, Gobius O'Shaughnessy [A. W. E.] 1875:145 [2] [Annals and Magazine of Natural History (Series 4) v. 15 (no. 86) (art. 19); ref. 18481] Nagasaki, Japan. Syntypes: BMNH 1870.12.2.1-2 (2). On p. 2 of separate. •Valid as Chloea castanea (O'Shaughnessy 1975) -- (Berg 1949:1072 [ref. 20662], Lindberg & Krasyukova 1975:384 [ref. 7348]). •Synonym of Chaenogobius annularis Gill 1859 -- (Okada 1961:676 [ref. 6363]). •Valid as Chaenogobius castaneus (O'Shaughnessy 1875) -- (Akihito in Masuda et al. 1984:276 [ref. 6441], Kawanabe & Mizuno 1989:613 [ref. 25598], Takahashi 1996:2 [ref. 24363], Kim 1997:432 [ref. 24032], Reshetnikov et al. 1997:754 [ref. 24702], Vasil'eva 1998:132 [ref. 23591], Sokolovskaya et al. 1998:13 [ref. 24670], Sato et al. 1998:41 [ref. 24972], Matsuura et al. 2000:221 [ref. 26000], Kim & Park 2002:356 [ref. 25913], Choi et al. 2003:398, 658 [ref. 26218], Stevenson 2002:272 [ref. 26489]). •Valid as Gymnogobius castaneus (O'Shaughnessy 1875) -- (Nakabo 2000:1200 [ref. 25182], Pietsch et al. 2001:145 [ref. 25688], Sakai et al. 2001:112 [ref. 25693], Bogutskaya et al. 2001:47 [ref. 26178], Nakabo 2002:1200 [ref. 26193], Yonezawa & Shinomiya 2002:2 [ref. 26563], Vasil'eva 2003:S45 [ref. 28444], Bogutskaya & Naseka 2004:222 [ref. 28183], Zhao et al. 2007:454 [ref. 29515], Shedko & Chereshnev 2005:441 [ref. 30089] in subgenus Chloea, Parin et al. 2014:485 [ref. 33547], Dyldin & Orlov 2017:189 [ref. 35257], Dyldin et al. 2021:35 [ref. 38804], Ito et al. 2021:[9] [ref. 38897], Parenti 2021:297 [ref. 38603]). Current status: Valid as Gymnogobius castaneus (O'Shaughnessy 1875). Oxudercidae: Gobionellinae. Distribution: Northwestern Pacific: Sea of Japan, Yellow Sea and Okhotsk Sea (China, Korea, Japan, Russia). Habitat: freshwater, brackish, marine.