Intraspecific colour preference in mate choice by female Apistogramma cacatuoides HOEDEMAN, 1951 (Teleostei: Perciformes: Cichlidae)

In mate-choice experiments females of the Neotropical cichlid Apistogramma cacatuoides unerringly differentiate between males of different populations and a red aquarium strain. Females use male colour traits to choose their mates. The preference of wild females for red-coloured males varies from 3 % to 69 % dependent on geographical origin, whereas aquarium-strain females prefer their own bright-coloured males in about 90 % of cases. The preferences of wild females show significant differences depending on their origin and following a geographical gradient. The high degree of stability in assortative mating behaviour in female A. cacatuoides may indicate incipient speciation processes.