Head Pores -
Scales - midlateral scales 32-38; predorsal scales not reaching eyes, remainder of head scaleless;
Fins - Dorsal rays VI + I, 8-10; anal rays I, 7-9; pectoral rays 18-21, the uppermost 6 rays forming free filaments (ie. not connected with adjoining rays by a membrane), usually the 1st and invariably the remaining five branching more than once; tail with 24-31 rays; pelvic disc rounded, front membrane with large side lobes.
Color - Generally olive green to brown with lighter scale centres; often a row of dark spots along midside and diffuse bars or saddle may be present on back; lower head with small white ocelli; first dorsal fin entirely pigmented, and with a central stripe; caudal and second dorsal fin with wavy brown bands or spots; 1st of 3 dark blotches behind eye is largest.
Size: grows to 11.4 cm.
Depth: 0-2 m.
Distribution - Southern Baja and the Gulf of California to northern Peru, Cocos Island, and the Revillagigedos and Tres Marias Islands of Mexico. According to Miller et al 2001 there are two subspecies - Bathygobius r. longipinnis from the Revillagigedos and Tres Marias, and Bathygobius r. ramosus from the remainder of the range
Habitat - Inhabits the rocky intertidal zone.