The caudal skeleton of mojarras from genus Eucinostomus (Perciformes: Gerreidae) and related species

Description and interspecific comparisons of the caudal complex in mojarras from the genus Eucinostomus and related species are presented for the first time. The caudal skeleton of Gerreidae species corresponds to the typical structure of the Percoidei suborder. This bony structure consists of five hypurals, three epurals, two uroneural pairs, autogenous hemal spines in the preural centra 3 and 4, and hypurals I+II and III+IV fused in pairs. Other elements and their characteristics are: parhypural with well-developed parhypurapophysis, urostyle formed by fusion of the preural centrum 1 and the ural centra I and II (UcI+UcII), preural centrum 2 with a specialized neural arch not very elevated and fused to the centrum, 17 principal caudal fin rays, a variable number of procurrent or secondary caudal fin rays (Cs), and the presence of a neural spine (Ns) in Pc3 and Pc4. Among gerreids there is an intergeneric and interspecific variation of osteological elements of the caudal skeleton that allows the taxonomic separation of studied taxa, and that can be, potentially useful to establish hypotheses of phylogenetic relationships in the family.