Species: Gambusia xanthosoma, Cayman Gambusia

Gambusia xanthosoma Greenfield, 1983

Cayman Gambusia

Head and body moderately robust, moderately compressed at rear; head depressed; front nostril not tubular; covering of eye not continuous with skin of head; mouth small, opens at front, slightly oblique, lower jaw slightly projecting, top jaw protractile; jaw teeth consist of an outer row of large backward curved teeth, and several rows of small pointed teeth; 13-16 gill rakers; 1 dorsal fin with short base, at rear of body, 9 (8-10) rays; anal fin origin distinctly before dorsal fin origin in both sexes, female with 11 rays; pelvic origin well behind pectoral base, near anal fin, tips of fins of males not swollen; pectorals high on flank, 14-15, modified in male, with 5th ray scalloped near its tip; 3rd anal ray unbranched; anal fin modified in male to form an elongate sex organ, that greatly elongate organ not slender, pointed with tip curved upwards and with 2 small recurved hooks on its top side, without a fleshy palp; tail base relatively narrow; tail fin rounded; scales smooth and relatively large, 29-31 in lateral series

Yellow to orange, most intense on lower part of tail base; abdomen and cheek with blue reflections; iris blue; a black line from upper corner of operculum back along ~3 scales; rear edges of scales with dark pigment spots; upper side with 5 longitudinal rows of black spots; dorsal and tail fins yellow-orange, with grey outer margin, crossed by 2 rows of black spots; pelvic and pectoral fins clear; anal fin of female white at front, orange in center, grey behind, that of male white and orange.

Reaches 4.4 cm.

Brackish water mangroves.

Depth: 0-1 m.

Grand Cayman Island.