Ctenogobius claytonii (Meek) 1902
Head Pores - Cephalic canals paired between the eyes from pore D anteriorly; Pores present A',B,C(2), D,F,H'; preopercle with pores _______
Scales - Scales in lateral series 34(29-39); ctenoid scales posteriorly, becoming reduced ctenoid anteriorly; no scales beneath pectoral fin axil; no scales on opercle
Fins - D1 - VI, third spine long and filamentous; D2 - 12(11-13); pectoral - 16(15-18); anal - 13(12-14); pelvic I,5 fin extending past anus in males, not reaching anus in females
Head - maxilla extending to under anterior 1/3 females, 1/2-2/3 in males; truncate or slightly emarginate; noistril tubular, near or at edge of snout; teeth in upper jaw in several rows, outer row in males enlarged, less in females; 4-6 teeth on each side of symphysis; teeth in lower jaw with strong recurved canines in midlateral jaw, several rows of teeth present.
Color - Generally very lightly pigmented; snout with streak from eye to midlateral jaw; cheek dusky with poorly defined markings; opercle faintly edged; top of head uniformally pigmented to vaguely mottled. Trunk with 5 midlateral blotches, sometimes with intermediate spots - the latter not being as well defined. Caudal fin in males with a dusky region over lower 1.2 which is divided by a clear submarginal strip; upper 1/2 faintly barred and dark elongate spot at upper edge near base. Females with lower margin dusky and remainder of fin with vertical bars. (Pezold 84)
Distribution - Veracruz, Mexico
Habitat - In streams and estuaries