Mouth brooding

Mouthbrooding, also known as oral incubation and buccal incubation, is the care given by some groups of animals to their offspring by holding them in the mouth of the parent for extended periods of time. Although mouthbrooding is performed by a variety of different animals, most notably Darwin's frog, fishes are by far the most diverse mouthbrooders. Mouthbrooding has evolved independently in several different families of fish.

Paternal mouthbrooders are species where the male looks after the eggs. Paternal mouthbrooders include the arowana, the mouthbrooding betta Betta pugnax, and sea catfish such as Ariopsis felis. Among cichlids, paternal mouthbrooding is relatively rare, but is found among some of the tilapiines, most notably the black-chin tilapia Sarotherodon melanotheron.

In the case of the maternal mouthbrooders, the female takes the eggs. Maternal mouthbrooders are found among both African and South American cichlids. African examples are the haplochromines, such as the mbuna, Astatotilapia burtoni, and the dwarf mouthbrooders Pseudocrenilabrus multicolor, and some of the tilapiines, such as Oreochromis mossambicus and Oreochromis niloticus. The South American maternal mouthbrooders are all members of the Geophaginae subfamily (commonly known as "eartheaters" on account of their substrate-sifting feeding mode) such as Gymnogeophagus balzanii and Geophagus steindachneri.

Biparental mouthbrooding occurs where both parents take some of the eggs. This is relatively rare, but is found among the cichlid genus Xenotilapia, and a single catfish, the spatula-barbled catfish (Phyllonemus typus).

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