Preliminary morphological characterization of dermal structures from three batoids species (Chondrichthyes: Batoidea) on Peruvian littoral

Some species of batoids have dermal coverage with morphological variations used for taxonomical research. This study characterizes the morphology of dermal structures of batoids landed on the Peruvian coast, according to the species, regions of the body, life stage and sex. Three species were analyzed: Pseudobatos planiceps, Rostroraja velezi and Sympterygia brevicaudata acquired from artisanal fisheries from the north to the south of the country. Three types of structures were identified: Dermal denticles, cutaneous tubercles and thorns. Diverse dermal structures are present since the birth of batoids. In Rajiformes, differences between sexes were the existence of malar and alar thorns in males. The presence of pores on the ventral side of tubercles and spines from Rhinopristiformes, differs from Rajiformes, which have a cavity where the skin will be attached and will extend to the pulp cavity of the spine. Differences on the morphology of dermal structures were related to the regions of the body evaluated and with the dermal covering pattern of the species. Furthermore, these results indicate that the methodology used in this study allows determination at the species level.