Astatoreochromis alluaudi

Astatoreochromis alluaudi is a scientifically famous Lake Victoria cichlid whose pharyngeal jaw morphology changes plastically in response to diet — fish raised on hard-shelled snails develop greatly enlarged, molariform pharyngeal teeth, while those raised on softer prey develop smaller, more generalised tooth morphology. This phenotypic plasticity has made A. alluaudi a key model organism in the study of cichlid jaw evolution and the mechanisms underlying the adaptive radiation of the Victorian cichlid flock.

In the aquarium, A. alluaudi is a moderately large, semi-aggressive cichlid that can be kept in a Victorian community with care. Providing snails as part of the diet is highly recommended to allow the expression of natural jaw development. The species is a maternal mouthbrooder.

For aquarists interested in evolutionary biology, A. alluaudi represents an extraordinary opportunity to observe phenotypic plasticity in action — a single species that can express dramatically different jaw morphology depending on its developmental diet history.