Cuban killifish (Cubanichthys cubensis), a fresh water fish endemic to Cuba

Scientific name: Cubanichthys cubensis
Common name (english): Cuban killifish
Common name (spanish): Killi cubano

The Cuban killifish (Cubanichthys cubensis) is an endemic species of Cuba, it is possible to locate mainly in the western region of Cuba, although it has been located in some areas of the central region. The name of the gender, Cubanichthys, comes from the name of the island and from the Greek ichthys that means "fish." Cubensis is a latin term that means "from Cuba".

The Cuban killifish inhabits on small ponds of scarce or null current, generally muddy. Equally in rivers of little depth, great aquatic vegetation or fallen vegetation. This Killifish can also be locate in next areas to the coast, generally in swamps.

The Cuban killifish has the cylindrical body, lightly wider and higher in its previous half. These fish fall into the usual size ranges for killifish: 3 inches for the males, and slightly smaller for the females. Coloration is muted: the body color is a mottled semi-transparent golden tan. A creamy white patch begins behind the gill covers and arches diagonally to the anal fin, encompassing the vital organs.

In both sexes, a series of horizontal light blue lines overlay the base color, beginning at the gill covers and extending through the caudal peduncle. A broken dark line often runs from the lower jaw through the center of the eye, and onto the upper gill cover.

In the males, coloration is brighter, and the more pronounced blue lines continue onto the bases of the anal and dorsal fins. As in many pupfish, the finnage on the males is more extravagant, with extensions to the dorsal and anal fins; the caudal may show a distinct wash of blue. The plainer females may show mottling or splotching along the midline of the body.

During a several day spawning period the females lay up to 10 eggs daily, laid one at a time on water plants. Occasionally a small cluster of eggs will be seen hanging from the female’s urogenital papilla on sticky threads. These are usually soon rubbed off on water plants. The eggs are fairly large, transparent, strongly adhesive, and measure 1.4 mm in size.