Species: Gobiosoma spilotum, Isthmian Goby

Gobiosoma spilotum (Ginsburg, 1939)

Isthmian Goby

Body robust, head rounded, wider than deep; very small barbel near anterior nostril; rear nostril a tube <1/3 height of front tubular nostril; 1 pore between eyes; 2 pores over opercle; preopercle with 3 pores; upper lip separated from snout by a groove along its top edge; upper jaw with 4 rows of teeth, outer row enlarged, inner not enlarged, no canines; lower jaw with 4 rows of teeth, outer row not enlarged, inner row slightly enlarged, no canines present; no teeth on roof of mouth; gill membranes broadly joined to body under throat, with 5 rays; dorsal fin VII (none filamentous) + I, 11 (10-11); length of 2nd dorsal base > distance from 2nd dorsal base to tail fin; anal fin I, 9 (8-9); pectoral fins 18-19 (18-20) rays, oval; pelvic I, 5, a complete disk, oblong to ovate, extending 3/4 distance to anus; tail fin rounded with 16 segmented rays; lateral scale rows 27-28 (26-29); scales extend in a broad band to upper and lower bases of pectoral fin, with narrow anterior bare areas above and below that band; four rough scales on tail fin base; no lateral line.

Dimorphic in color; males uniformly dark grayish brown with a mid-lateral row of seven black dashes between the pectoral base and the tail fin, sometimes an eighth spot on the tail base; belly pale; head mottled; a dark vertical area behind and above the corner of the mouth, a dark vertical line along the preopercular margin, and three dark spots along the sides; lips and chin dark; females are mottled and appear barred, the seven irregular bars passing through the seven black spots which are less distinct; seven dark areas along the base of the dorsal fins; belly pale.

Size: 2.7 cm.

Habitat: coastal rock and algal habitats.

Depth: 0-2 m.

SW Caribbean.