Head relatively short - < 25% of SL, top profile straight; sensory system on snout with L shaped furrows at front; top jaw extendible, top of front bone relatively straight, doesnt reach under front of eye; first dorsal large, II-V spines, front spine longest, origin ~over anal origin; second dorsal margin straight to concave; anal fin 20-26 (usually 21-22) rays, rear margin concave; pectoral reaches to tip of pelvic; none to 1 row of scales on bases of first 5 rays of anal fin; 35-40 (usually 37-38) lateral line scales, 6 transverse rows of scales.
Lateral stripe width < eye diameter, broadens and becomes diffuse on tail base.
Size: 9.5 cm.
Habitat: estuaries, coastal lagoons and in rivers.
Depth: 0-10 m.
The SE corner of the Gulf of California to Costa Rica