Head flattened, with puffy cheeks; 1st dorsal fin with VII spines; tip of tongue notched; pore between middle of eyes but none in front of eyes; no barbels on head; no scales; preopercle with 2 pores & 1 small barbel on its edge; pelvics fused to form disc; no scales.

The genus contains a single species, which is endemic to the tropical eastern Pacific.

histrio (Jordan 1884)  

Aruma Ginsburg 1933a: 16 Type species: Gobiosoma occidentale Ginsburg 1933:16-17, by original designation; erected as a subgenus of Gobiosoma.