Order Cyprinodontiformes
Superfamily Cyprinodontoidae
Family Fundulidae
Genus Adinia
— Adinia xenica [Jordan & Gilbert, 1882] — Diamond Killifish. Code: XEN. Synonym: Adinia multifasciata, Fundulus xenicus. Brackish lagoons of the USA from Texas to Florida. 4-6 cm. It has a curved back profile. Brownish or dark grey with 10-14 uneven transverse silvery lines. Unpaired fins range from dark grey to almost black, with silver spots and stripes. The dorsal fin usually has a white border, and the anal fin may have a yellowish tint. The female is paler in color without stripes, unpaired fins are shorter than in the male, with grey speckles.
Peaceful, active, develops better in groups of 6 to 10 adult fish, compatible with other brackish-water fishes. It is aggressive only in small tanks and when shelters are absent. Shelters made of stones and roots, moderate vegetation of brackish-water plants (Vallisneria) are required. These are brackish water fish; for their well-being, sea salt or table salt should be added to the water (2-3 tablespoons per 10 liters). In natural conditions, salinity can range from 5 to 35%. T 20-23°C.
Genus Leptolucania
— Leptolucania ommata [Jordan, 1884] — Pygmy killifish. Code: OMM. Synonym: Heterandria ommata. Leptolucania lives in the swamps of Georgia and Florida, always securely hiding in dense vegetation. Reaches a length of about 2.5 cm. The body has a pale yellow or amber coloration. The male is smaller than the female, with yellowish-brown flanks, a dark stripe running down the middle of the body, and a black round spot with a golden border at the base of the tail. On the rear half of the body, there are up to eight black vertical stripes, the dorsal fin is yellow with a blue tip, and the caudal fin is the same color but with a red tip.
The female is slightly lighter, lacks vertical side stripes, but has an “eyespot” directly above the pelvic fin, and a large black spot at the base of the caudal fin. Very cautious and timid. Should be kept in a small separate aquarium; otherwise, it simply will not withstand competition with larger aggressive fish. Temperature 20-28°C.
Genus Lucania
— Lucania goodei [Jordan, 1880] — Bluefin killifish. Code: GOO. Synonym: Chriopeops goodei. This fish lives in Georgia and Northern Florida in swamps with soft, acidic water, staying very close to the safe, densely overgrown bottom. 4-6 cm, females are slightly larger than males. The body is elongated, the dorsal fin is set back to the rear half of the body. The caudal fin is rounded and convex. There are populations that differ in coloration and body shape. Almost year-round, this tiny creature remains deceptively dull with an olive-brown back, paler belly, and a black lateral stripe extending from the snout to the tail.
The fish transform only during the breeding season. The dorsal and anal fins of the male are always black at the base, but in spawning colors, he becomes strikingly attractive. During this period, the dorsal and anal fins are flooded with sparkling iridescent blue, and delicate red strokes appear on the tail – a most pleasant color combination. The male’s body is olive-green to grey-brown, covered with a dark reticulated pattern, the belly is pale.
A jagged dark coffee longitudinal stripe runs from the snout through the eye to the caudal fin. The dorsal and anal fins are large, brilliant blue, except for the black bases and margins, quite high and almost always spread out. The caudal fin is pink, the base of the tail is red. The female is brownish-yellow, almost grey, with a longitudinal black zigzag stripe, the base of the tail is whitish. Females have colorless fins.
Can be kept in a community aquarium, but preferably in a species tank in a group. To succeed in keeping and breeding the bluefin killifish, it needs a separate species aquarium with conditions similar to its natural habitat. A pair requires a volume of at least 20 liters. They occupy the middle and lower water layers, prone to panic attacks. A diurnal fish that feels well both in a school and individually. When dividing territory, males become brightly colored and display in front of each other. Fights usually do not occur.
The aquarium should be well planted with fine-leaved plants. Cannot be kept with very active and predatory fish. Slightly alkaline water with pH 7.2 and hardness around 10° is most favorable; they fall ill in soft water. Fed with live foods. Compared to its relatives, Lucania has adapted to slightly cooler conditions; a temperature of about 21°C is sufficient for spawning, while most tropical fish sometimes need 10°C more. Spawns among bushy plants. Lifespan up to 2 years. dH 12-16°; pH 6.5-7.2; T 18-23°C.
— Lucania parva [Baird & Girard, 1855] — Rainwater killifish. Code: PVA. Eastern coast of the USA to Mexico, as well as in the central regions and western coast of the USA — a coastal species inhabiting calm brackish and marine waters. It can migrate to water with lower salinity and returns back after spawning. 5-6 cm. A variable species, with the Florida population being the most brightly colored. Resembles large guppies in appearance. The body is laterally compressed, the mouth is small and upturned, the head is smoothed on top, the snout is blunt. Dorsal and caudal fins are rounded. Unassuming coloration, pale brownish-olive, flanks slightly lighter silvery, belly white.
The main distinguishing feature of the species is the dark brown or black border on each scale, which gives the fish a mail-like pattern, especially noticeable in larger adult specimens. During the breeding season, males develop a black spot in front of the orange dorsal fin. The caudal, anal, and pelvic fins are colored red-orange with a black border. The anal fin has a yellowish tint. Females are larger than males, fins are transparent.
Can be kept with peaceful fish. Aquarium with thickets of live plants, driftwood, hiding places. Water volume per pair of fish is 30 liters. Occupies the upper water layers. When pursued by a predator, it can jump out of the water and lie on its surface (on its side) for up to 10 seconds, then dive back into the water. Feeds on small crustaceans and aquatic insect larvae. It is advisable to add sea salt or table salt to the water (up to 4-5 tablespoons per 10 l). Sexual maturity at 3-6 months, at a size of 25 mm. Lays eggs on plant leaves. Temperature 20-24°C.
Fundulus chrysotus, Fundulus cingulatus.
Cyprinodon bovines, diabolis, elegans, macularius, variegatus. 
Last changes and additions were made on April 2, 2012.
