Distinguished by the very blunt teeth, the lack of a distinct median tooth on the tongue and the lack of posterial teeth (Ref. 27547). Anterior dorsal fin lower than the posterior, arising well back on body; caudal fin joined to both dorsal and anal fins; anal fin small, represented in males by a low ridge (Ref. 27547). Females with a pointed 2nd dorsal fin and a conspicuous anal lobe (Ref. 1998). Back and sides dark gray to brown, ventral side of body whitish (Ref. 27547); fins translucent olive-green and the caudal fin with diffuse black pigment (Ref. 1998). Oral disc narrower than head; usually 58-67 trunk myomeres; caudal fin with dark spot (Ref. 86798). Other adult diagnostic features: 8.0-15.4 cm TL. Body proportions, as percentage of TL (based on 45 specimens measuring 10.1-15.4 cm TL): prebranchial length, 10.4-14.0; branchial length, 8.3-10.8; trunk length, 44.7-53.1; tail length, 25.2-30.4; eye length, 2.0-2.7; disc length, 4.1-7.9. Urogenital papilla length, as a percentage of branchial length, in 26 spawning males measuring 12.2-15.1 cm TL, 17.6-30.8. Trunk myomeres, 60-67. Dentition: supraoral lamina, 2 unicuspid teeth; infraoral lamina, 7-10, usually 7 unicuspid teeth; 3 endolaterals on each side; endolateral formula, typically 1-2-1 (15 cases), 2-2-1 (12), or 2-2-2 (10), and rarely 2-3-2 (5) and 2-3-1 (1); 2 rows of anterials; first row of anterials, 4-6 unicuspid teeth; exolaterals absent; posterials usually absent; transverse lingual lamina, 5-11 unicuspid teeth, the median one enlarged or only the median enlarged tooth is present; longitudinal lingual laminae cusps too small to count. Velar tentacles, 5-6, with tubercles. Body coloration (preserved), dorsal and lateral aspects grayish, ventral surface whitish. Lateral line neuromasts unpigmented. Extent of caudal fin pigmentation, 75% or more. Fleshy tissues around the lingual laminae unpigmented. Caudal fin shape, rounded or spade-like. Oral fimbriae, 93 (Ref. 89241).