Mouthbrooding is so common in cichlids that many aquarists may not realize that it is a rare and specialized form of parental care. Mouthbrooding has evolved at least eight different times in fishes in such diverse groups as arowanas, silurid catfishes, cardinalfishes, jawfishes, and anabantoids (Oppenheimer, 1970), but the habit has reached its zenith in cichlids, where the behavior has developed independently in South American, West African, and African rift lake subgroups.