Cichliformes

Cichliformes is an order of ray-finned fishes that groups together the cichlids and their close relatives. The most species-rich family within the order is Cichlidae, the cichlids, which includes hundreds of genera and over a thousand described species. Cichliformes fishes are primarily freshwater, with some species tolerating brackish conditions, and are native to Africa, Madagascar, and the Neotropical regions of Central and South America.

Cichlids occupy a wide range of habitats, from rivers and floodplain lakes to large tropical lakes. They exhibit considerable diversity in body form, coloration, and behavior. A hallmark of many cichlids is extensive parental care, including nest guarding and various levels of mouthbrooding, where one or both parents protect and transport eggs and young. Courtship displays and color changes are common, contributing to species recognition and mating.

Evolutionary significance: Cichlids are a classic model for studying adaptive radiation and speciation. In Africa’s Great Lakes—Victoria, Malawi, and Tanganyika—rapid diversification has produced numerous closely related species that occupy specialized niches in feeding, habitat, and behavior. The Neotropical cichlids likewise show substantial diversity, with multiple radiations and ecological roles across rivers and lakes.

Human interactions: Cichlids are central to the aquarium hobby and are important to freshwater fisheries in several regions. They are sensitive to environmental changes, and many species face threats from habitat destruction, pollution, and competition or predation by introduced species. Research on cichlids has contributed to broader understandings of evolution, behavior, and ecology.