Competition Between Color Morphs of the Midas Cichlid, Cichlasoma citrinellum, in Lake Jiloá, Nicaragua

Authors

Kenneth R. McKaye, University of California - Berkeley
George W. Barlow, University of California - Berkeley

Date of this Version

1976

Comments

Published in INVESTIGATIONS OF THE ICHTHYOFAUNA OF NICARAGUAN LAKES, ed. Thomas B. Thorson (University of Nebraska-Lincoln, 1976). Copyright © 1976 School of Life Sciences, University of Nebraska-Lincoln.

Abstract

Color polymorphism, or polychromatism, is a recurring phenomenon throughout the animal kingdom. In fishes one form, the goldfish, is particularly notable because of its conspicuousness and its occurrence in nature in such a large number of widely unrelated species; yet it is seldom common in anyone species (Webber et al., 1973). The Midas cichlid, Cichlasoma citrinellum, is unusual in this respect because in many of the lakes where it occurs in Nicaragua brilliantly colored morphs are relatively common. These morphs lack the species-typical dark markings, and individuals vary smoothly from white through yellow, orange, red, and mixtures of these. The most abundant morph, however, is golden orange, which we term gold and use collectively here for all the brilliantly colored fish; the cryptically patterned common gray morphs are called normals.