Redescrição de Schroederichthys saurisqualus Soto, 2001 (Chondrichthyes, Carcharhiniformes, Scyliorhinidae) da costa sul e sudeste do Brasil

Abstract

Schroederichthys saurisqualus Soto, 2001 are represented by small oviparous sharks (reaching up to 692 mm in total length), usually associated with consolidated substrates such as corals, tube sponges and gorgonians, and can be found at depths up to 250 m. In this study the geographical distribution of the species was extended to São Paulo. It shows a color pattern with black and white spots and saddles arranged throughout the body, which allowed to purpose a new nomenclature for this pattern, which could be used for other species of the family, described only on the basis of color. Large liver occupying almost the entire visceral cavity showed to be important taxonomically. A new approach on the counting of lateral theeth cusplets was proposed indicating the presence of three to five in males and females from three to nine. A new tooth series was found, which varied from alternated type to alternated independent type, showing to have a major relevance for taxonomy and sexual dimorphism. The neurocranial morphology proved to be extremely important when compared to other species of the genus. The clásper revealed anatomical structures unknown to the species, such as the accessory dorsal marginal 4, which is linked to the accessory dorsal marginal 2 and below the accessory dorsal marginal 3. Regarding the branchial arches, a fusion between the fourth and fifth pharingobranchials was observed. The data obtained here are potentially useful in future taxonomic and phylogenetic studies of the genus