Order Cyprinodontiformes ( Cyprinodontiformes )
Suborder Cyprinodontoidei ( Cyprinodontoidei )
Family Poeciliidae ( Poeciliidae )
Subfamily Poeciliinae ( Poeciliinae )
Genus Poeciliopsis — Poeciliopsis.
— Porthole Livebearer — Poeciliopsis gracilis [Heckel, 1848]. Synonym: Gambusia, Xiphophorus heckeli, Priapichthys letonai. (Eng. Porthole Livebearer). Mexico, Guatemala. Male 4, female 7 cm. The delicate pastel coloration of the fish is perfectly complemented by several anthracite spots and rare “electric” sparkles flashing on the sides when moving in reflected light. The brightness of the spots depends on the mood and condition of the fish. Fins are colorless.
The fish are very active and need a spacious aquarium, keep them in a group of 2 males and 5 females. Small fish can be eaten. They can be kept in a general aquarium with fish similar in care and size. Presence of plants, bright light, and warm (25-27°C) water are desirable. They react sensitively to the slightest deterioration in water quality and a change from one food to another. Aeration and filtration should be round-the-clock if possible. Water can be salted up to 3%. Favorite foods: Cyclops, Moina, small aquatic larvae, bloodworms, Corethra. Tubifex is completely unsuitable due to toxicosis and tuberculosis syndromes. Salt additives are very useful for maintaining the health of the fish. Pregnancy of the female takes about three weeks. Life span 3-4 years. T 24-28°C; pH 6.5-7.8; dH 6-20°.
— Upper Grijalva Livebearer — Poeciliopsis hnilickai [Meyer & Vogel, 1981]. (Eng. Upper Grijalva Livebearer). Mexico. Male 3.5 cm, female 5 cm. Back is gray-green, the rest of the body is silvery with a black-blue longitudinal stripe. There is a yellow form with a greenish stripe. Live up to 3 years. T 24-27°C; pH 6.5-7.5; dH 6-18°.
— Blackspotted Livebearer — Poeciliopsis turneri [Miller, 1975]. (Eng. Blackspotted Livebearer). Mexico. 3 cm, female is much larger. Body is beige with reticulated scales and bluish sparkles on the body. There is a black spot at the base of the tail. Short dark brown stripes run along the side of the body. T 24-28°C; pH 7.0-7.8; dH 5-15°.
Priapella compressa, Priapella intermedia.
Phallichthys amates, Phallichthys fairweatheri, Phallichthys tico. 
