Redescription and designation of a neotype for Ophiothrix angulata (Say, 1825 (Echinodermata: Ophiuroidea: Ophiotrichidae)

Abstract

Ophiotrichidae Ljungman, 1867 comprises brittle stars diagnosed by the absence of oral papillae and presence of a cluster of dental papillae covering at least half the height of the dental plate. Ophiothrix Müller & Troschel, 1840 is the largest genus in the family and is composed of many species with a highly variable morphology. Ophiothrix angulata is one species with descriptions showing morphological variation in many of the diagnostic characters stated by Say (1825) in the original description. Say's (1825) type material and specimens studied by him could be located. Thus, in order to elucidate the taxonomic identity of O. angulata and following Article 75 of the International Code for Zoological Nomenclature, here we propose the neotype designation of O. angulata based on topotype specimens from South Carolina, United States. A discussion of the records of O. angulata from the Atlantic Ocean is included. Taxonomic comments on the genus Ophiothrix are also provided.

Guia ilustrado dos Echinodermata da porção sul do Embaiamento Sul Brasileiro

“…De cinco a oito espinhos braquiais longos, translúcidos e com as margens denteadas. A partir do quarto ou quinto segmento braquial, espinho mais ventral menor e modificado em gancho, com dentes hialinos voltados para o disco (Borges & Amaral 2005;Santana et al 2017;Alitto et al 2018).…”

Atlantic West Ophiothrix spp. in the scope of integrative taxonomy: Confirming the existence of Ophiothrix trindadensis Tommasi, 1970

“…Main morphological characters of all CSs with Ophiothrix angulata –original description [24], redescription [29] and specimens from type locality (USMN); O . trindadensis –original description [10].…”

“…Group 2 included all the O . angulata from original description [24], the redescription [29], samples from type locality (USNM) and CS3. Their main characteristics are the absence of longer hyaline spines scattered on the disc, absence of denticulate spines on the disc, absence of the carena on dorsal arm plate, and five to nine arm spines.…”

“…Description. Original description in Say [24], neotype description in Santana et al [29], microstructures description in Alitto et al [30].…”

“…In relation to O . angulata , the CSs were compared to its original description [24], redescription [29] and samples from type locality (South Carolina, United States) available from USNM (vouchers E24138–9 spms, E28587–5 spms, 33710–4 spms). They were also compared with the original description of O .…”