Eugnathogobius Smith, 1931

Eugnathogobius Smith, 1931 View in CoL View at ENA

Eugnathogobius Smith 1931 View in CoL ( Eugnathogobius microps Smith, 1931: 37 View in CoL , Fig. 18 View Fig , lower Bangpakong River, central Siam, by original designation and monotypy).

Eugathogobius Koumans, 1931: 69 (error for Eugnathogobius View in CoL ).

Calamiana Herre, 1945 ( Calamiana magnoris Herre, 1945: 80 View in CoL , Calamianes, the Philippines, by original designation and monotypy).

Gnathogobius Smith, 1945 ( Gnathogobius aliceae Smith, 1945: 523 View in CoL , Fig. 104, Bangkok, Thailand, by original designation and monotypy).

Diagnosis. – Distinguished by following combination of characters. Second dorsal fin rays I,6-9; anal fin rays I,5-9; unpaired fin rays modally equal in number; first dorsal spine may be elongate; pectoral fin rays 14-20; 16 or17 segmented caudal fin rays in 9/7 or 9/8 pattern; predorsal scales variable, absent or 2-25; 23-63 scales in lateral series; TRB 7-22; 12-25 circumpeduncular scales; headpores present in three species, absent in five; headpores, if present, reduced (no rear part of oculoscapular canal, no preopercular pores, no nasal pores); preopercular pores absent; sensory papillae in longitudinal pattern; papillae rows a and c consisting of large, widely spaced papillae, as does row p if present (otherwise replaced by headpores), rows b and d always consisting of small close-set papillae, row f of one or two papillae only, two or three s rows on snout of one papilla each; modally two but up to three s papillae rows on snout; papillae rows p, a and c composed of few large widely spaced papillae, other papillae small and close-set; papilla row c broken under eye, rear portion consisting of one papilla, papilla row e curves upward onto the cheek in advance of the preopercular margin (variably developed); gill opening restricted to pectoral fin base or extending past pectoral base to under opercle; smooth bony or fleshy flange or ridge on pectoral girdle, with no fleshy knobs and flaps; jaws terminal with lower jaw tip usually anteriormost, jaws may be enlarged in males (may be greatly enlarged in some species); inner edges of lips smooth, without fimbriae; anterior nostril tubular, placed at or just behind preorbital edge; genital papilla flattened and usually elongate in males, rounded and bulbous in females; gut simple, S-bend shape.

Pterygiophore formula 3-12210; 26 vertebrae, modally 10+16; two epurals; two or three (rarely one) anal fin pterygiophores present before first caudal haemal spine; anterior end of preopercular bone blunt, rounded or slightly pointed; neural spines of first few vertebrae slender, pointed; neural spines on first few vertebrae slender, tips not broadened (except in some specimens of E. kabilia ); metapterygoid short, relatively small, may be broadened dorsally or with short dorsal process, but not contacting or forming bridge to quadrate in three species, metapterygoid forming distinct low bridge to quadrate in six species; palatine and pterygoid slender and nearly equal in length; palatine reaching quadrate; quadrate broad, may be somewhat forked; fifth ceratobranchial stout, triangular, with high flange fifth ceratobranchial narrow and triangular, with distinct flange on back (extra crest on back in one species); four to nine ossified gill-rakers; scapula usually unossified but tip above foramen may be ossified.