First record of melanism in Cheilodactylus variegatus Valenciennes, 1833

• Published in: Latin american journal of aquatic research Vol. 43; no. 3; p. 588
• Main Authors: Flores, Hector, Poblete, Hugo
• Format: Journal Article
• Language: Spanish
• Published: Pontificia Universidad Catolica de Valparaiso, Escuela de Ciencias del Mar 01.07.2015
• Subjects: Costa Rica
• ISSN: 0718-560X; 0718-560X
• DOI: 10.3856/vol43-issue3-fulltext-21

Melanism in fish is rare; it is expressed in a greater number of limnetic species rather than marine. The capture of a Cheilodactylus variegatus female specimen with full melanosis is reported. The individual was captured with harpoon by apnea diving, in the Caleta Piedra Azul, northern Chile. Its standard length was 33.6 cm and a total weight of 960 g. There is no morphological difference if compared with normal color specimens. The general coloration of the body is dark gray, with slightly lighter vertical stripes on the flank. No fins show the orange hue characteristic of the species. The validity of trematode infection effect as a causal agent of melanosis is discussed, because it is a mutation in the melanocortin receptor (MC1R). The melanosis condition in Ch. variegatus, is very rare. It is the first time that this phenomenon is reported for this species, where the expression of a dark color, would be beneficial to specimens who reside on bottoms with little vegetation and among crevices.