Order Cyprinodontiformes
Suborder Cyprinodontoidei
Family Goodeidae
Subfamily ( Goodeinae )
Genus Skiffia.
— Twoline Skiffia — Skiffia bilineata [Bean, 1887]. Synonym: Characodon bilineatus, Goodea, Neotoca bilineata. Central Mexico, Lerma River. Male 4, female 6 cm. Greenish-silver colored fish with a brilliant bluish sheen, featuring a horizontal black line starting at the gill covers, curving downwards, and then running straight to the caudal peduncle.
The second line, located lower, extends from the gill covers to the belly area, where it is enclosed by a wide vertical stripe running from the center of the body to the belly. Fins are smoky with large black spots. Anal fin is transparent, and the dorsal fin is large. Completely peaceful, with no aggression even between males. These are small, slow-moving fish, staying mostly in the middle water column, always scattered throughout the aquarium.
They tolerate temperatures above 26°C poorly; males fade, and life expectancy is significantly reduced. They feed mainly on algae, which is an important part of their diet. However, they accept any aquarium food. After 40-50 days of gestation, about ten large fry (up to 12 mm) are born, growing quite rapidly. Fry behave like adults immediately after birth. dH up to 20°; pH 7.0-8.0; T 21-24°C.
— Golden Skiffia — Skiffia francesae [Kingston, 1978]. Mexico. 5 cm. Body golden-gray, fins gray. Irregular black spots on the flanks. In males, the large dorsal and anal fins are black. Females are much simpler in color. A very beautiful aquarium hybrid “Black Beauty” has been bred by crossing Skiffia francesae and Skiffia multipunctata. It is advisable to keep them in large groups of at least 10 individuals.
Best kept in an aquarium with a minimal number of other species, with hiding places where they can take refuge. Males try to establish a hierarchy by trying to impress each other, spreading their fins, and showing off their beautiful coloration. Regular weekly water changes must be performed. After 8 weeks of gestation, 20-30 fry with a length of 8-11 mm appear. pH 7.0-9.0; dH up to 20°; T 20-25°C.
— Pleket Skiffia — Skiffia multipunctata [Pellegrin, 1901]. Synonym: Goodea multipunctata, Ollentodon multipunctatus, Xenendum multipunctatum. Mexico, Lerma River. Male 5, female 6 cm. Body has a dirty-yellow base color with iridescent scales, covered with dark pigmented spots. In males, black spots grow with age and can cover the entire body. Dorsal fin is irregular in shape with ragged edges. Tail base, dorsal, and caudal fins are yellow. Females are larger and less colorful.
Active, should be kept in as large groups as possible. Generally peaceful, but may be aggressive towards other males and other species. Sandy bottom is preferred. They prefer hard, slightly alkaline water, although some live in soft water habitats. They show high susceptibility to deteriorating water conditions. They accept all types of dry, frozen, and live foods. It is important to add plant matter. The average number of offspring at birth ranges between 10 and 20 fry up to 10 mm in length. T 23-27°C; pH 6.5-8.0.
Identification: Genus Skiffia.
Xenotoca eiseni, Xenotoca melanosoma, Xenotoca variata.
Ilyodon furcidens, Ilyodon whitei, Ilyodon xantusi. 
