The egg-spots of haplochromine cichlids as exemplified in <i>Astatotilapia burtoni</i>.

<p>(A) A male of <i>A. burtoni</i> showing egg-spots on its anal fin. (B) Natural variation of egg-spots in <i>A. burtoni</i>. All these fish were caught and photographed at the south-eastern part of Lake Tanganyika in Zambia. (C) A typical courtship and mating cycle of a haplochromine starts with a lateral display of the male, to which the female responds; she then lays a clutch of eggs and immediately takes them up into her mouth. The male then presents the egg-spots on the anal fin; the female seemingly nuzzles at these egg-spots and the male releases sperm so that the eggs are fertilized within the females' mouth. The eggs and larvae then stay in the buccal cavity of the female for a period of several days to a few weeks. The arrow points to the location of an egg that the female is taking up into her mouth.