Herichthys cyanoguttatus

Herichthys cyanoguttatus holds a unique distinction as the only cichlid species native to the United States, occurring naturally in the Rio Grande and its tributaries in Texas. It is also found in northeastern Mexico. Despite being an unusually northerly cichlid, it is no delicate fish — it is a hardy, powerful species that has adapted to a wide range of temperatures, water hardness levels, and turbidity conditions.

Adults are impressive: a pale grey body covered with hundreds of iridescent blue-green to turquoise spots that sparkle under aquarium lighting. In breeding condition, both sexes develop a white or cream anterior body contrasting a dark posterior — a pattern known as a breeding dress that makes them momentarily among the most striking aquarium cichlids. Males develop a prominent nuchal hump.

Care is straightforward given the species' hardiness, but its aggression and digging behavior require robust aquascaping. It is a territorial omnivore that will destroy plant-based decor and challenge similarly sized tankmates during breeding.

Water: 20–28°C, pH 6.5–8.0, GH 5–20, KH 3–12; very tolerant of parameter variation; cold-tolerant. Tank: 350 L minimum; heavy rocks, sand substrate; avoid live plants; powerful filtration. Feeding: Omnivore — cichlid pellets, earthworms, frozen mysis; accepts virtually any food offered. Breeding: Open flat-rock spawner; very aggressive brood defense; 500–800 eggs per clutch. Compatibility: Large robust CA cichlids; its tolerance for cool water allows mixed setups with some temperate species.