Yano?s cheek-hook goby (Ancistrogobius yanoi)

Biology

Dorsal spines (total): 7; Dorsal soft rays (total): 10; Anal spines: 1; Anal soft rays: 9. This species differs from its congeners in having the following set of characters: no scales on head and most of nape (no predorsal scales); third spine of first dorsal fin elongate and filamentous, obviously longer than preceding spine (at least in specimens that are more than 21 mm SL), with alternating pale and dusky pattern in life or when fresh (typically faded and indistinct in preserved specimens, but its distal tip tinged with black); 17-19 (usually 18 or 19) pectoral-fin rays 1; pelvic fins fused medially by well developed connecting membrane and frenum (frenum often rudimentary); fifth segmented ray of pelvic fin 89.9-100.0% of preceding ray in length; faint, dusky blotches below eye (not forming a distinct vertical bar); distal tip of first dorsal fin with a black blotch, relatively wide, extending posteriorly to just behind third spine (but not to middle of third inter

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