Rhinogobius mizunoi, A New Species of Freshwater Goby (Teleostei: Gobiidae) from Japan

A new freshwater goby, Rhinogobius mizunoi, is described based on six specimens from a freshwater stream in Shizuoka Prefecture, Japan. The species is distinguished from all congeneric species by the following combination of characters: I, 8 second dorsal-fin rays; 18–20 pectoral-fin rays; 13–18 predorsal scales; 33–35 longitudinal scales; 8 or 9 transverse scales; 10+16=26 vertebrae 26; first dorsal fin elongate in male, its distal tip reaching to base of fourth branched ray of second dorsal fin in males when adpressed; when alive or freshly-collected, cheek with several pale sky spots; caudal fin without distinct rows of dark dots; a pair of verticallyarranged dark brown blotches at caudal-fin base in young and females.