Range and prominent phenotypic differences of members of the Midas cichlid species complex. (A) Map of the Pacific coast of Nicaragua in Central America. Besides the large Nicaraguan lakes (Managua and Nicaragua), multiple crater lakes (Asososca Leon, Apoyeque, Xiloá, Asosoca Managua, Masaya and Apoyo) have appeared in the course of the last 25,000 years. These crater lakes have been colonized by Midas cichlids from the large lakes, resulting in new species. (B) Midas cichlids from Lake Xiloá, Amphilophus xiloaensis, the focal species of this study. (C) Three selected traits that are interesting from an evolutionary-developmental angle. In the large lakes and in many crater lakes, cichlid species and morphs show differences in coloration, body shape and lip shape.