Karyotypical Studies on Dormitator maculatus Bloch and Gobiomorus dormitor Lacépède (Gobiidae: Perciformes)

Abstract

The cytogenetic study of Dormitator maculatus and Gobiomorus dormitor, fish species belonging to the family Gobiidae, was made. The studied specimens were collected in the Papaloapan river mouth and Alvarado Lagoon in the coast of the Gulf of Mexico. The methodology employed to obtain the karyotype is described. The diploid number found for D. maculatus is 46 and its fundamental number is 90. G. dormitor has 48 chromosomes and its fundamental number is 54. No evidence of heterochromosomes was found in either species. The numerous differences between their karyotypes do not denote close phylogenetic relationship between them.