Taxonomy of Ophiuroidea (Echinonermata) from the continental shelf and slope of the southern and southeastern Brazilian coast

Abstract

This study focuses on the ophiuroids collected during the Programme of Evaluation of the Living Resources of the Exclusive Economic Zone for the Brazilian coast (REVIZEE), South Score/Benthos, in the states of Rio de Janeiro (Ilha Grande Bay), São Paulo, Paraná, Santa Catarina and Rio Grande do Sul (Tramandaí) (24° 07,113' S and 29° 48,500' S; and 43° 46,759' W and 49° 06,800' W). Samples were collected on the continental shelf and slope (60-810 m) using the following equipment: van Veen, box corer and a rectangular dredge. Individuals were identified, measured and photo-graphed under a stereomicroscope and a scanning electron microscope. Growth series of the species that contributed with more than 10 individuals were analysed. A total of 5044 individuals were collected and were represented by 29 species, which belonged to seven families. The most abundant species were Ophiura ljungmani and Ophiomisidium pulchellum, which represented 79.7% of the total number of individuals. The analyses and description of species as well as the organization of the growth series allowed the verification that some characteristics of morphological structures used for the identification of the group remain unaltered throughout the life of the organism, whilst others undergo alterations. We recorded two new occurrences for the Brazilian coast: Ophiostriatus striatus and Amphilimna mirabilis. The ophiuroid fauna is composed of species with wide distribution along the Brazilian coast, such as Ophiothrix angulata and Amphipholis squamata, species with occurrence restricted to certain areas, such as Ophioleptoplax brasiliana and Nudamphiura carvalhoi. Most species were collected within the bathymetry limits previously described for them.