Redescription of Hemieuryale pustulata von Martens, 1867 (Echinodermata, Ophiuroidea) based on Brazilian specimens, with notes on systematics and habitat association

Abstract

We redescribe Hemieuryale pustulata on the basis of 325 specimens obtained from the continental shelf off northeastern and southeastern Brazil. This is the first record of the species for Brazil. We illustrate for the first time details of the dental plate, oral plate, and vertebrae. Few morphological variations were observed in our extensive material. All specimens were associated with the gorgonian Nicella guadalupensis, suggesting an obligatory association in the Brazilian littoral. H. pustulata did not reveal a particular pattern of distribution on its host gorgonian, but larger gorgonians tend to support a larger number of ophiuroids. In addition to expanding the knowledge on morphology and ecology, we extend the known bathymetric distribution of the species, which is now known from 18 to 330 m.Key words: Brittle-stars, Hemieuryalidae, morphology, taxonomy, ecology ResumoEste estudo apresenta uma redescrição para Hemieuryale pustulata a partir de 325 espécimes obtidos na plataforma continental do nordeste e sudeste brasileiro, sendo este o primeiro registro da espécie para o Brasil. São descritos e ilustrados pela primeira vez alguns caracteres internos para esta espécie, tais como placa dental, placa oral e vértebras. Poucas variações morfológicas foram observadas nos exemplares estudados. Todos os espécimes analisados estavam associados à gorgônia Nicella guadalupensis, sugerindo uma associação simbiótica obrigatória no litoral brasileiro. H. pustulata não apresentou um padrão claro de distribuição na gorgônia-habitat, porém, pode-se constatar que gorgônias maiores abrigam maior abundância de indivíduos. Além dos dados morfológicos e ecológicos apresentados, este estudo amplia o intervalo de faixa batimétrica desta espécie, agora conhecida de 18 a 330 m de profundidade.

Non-destructive morphological observations of the fleshy brittle star, Asteronyx loveni using micro-computed tomography (Echinodermata, Ophiuroidea, Euryalida)

“…Recently, the micromorphology of the ossicle surface (e.g., articulation forms of lateral arm plates) have become heavily used as taxonomic characters of ophiuroids (e.g., Stöhr et al 2008; Stöhr and Muths 2010; Okanishi and Fujita 2009, 2011, 2013; Martynov 2010; Thuy and Stöhr 2011; Gondim et al 2015; Thuy and Stöhr 2016). On the other hand, internal structures of ossicles, such as radial water canals and radial nerve canals in vertebrae, have scarcely been observed and their taxonomic significance has never been discussed.…”

A New Morphological Phylogeny of the Ophiuroidea (Echinodermata) Accords with Molecular Evidence and Renders Microfossils Accessible for Cladistics

“…Dissociated skeletal parts of fossil ophiuroids were extracted from the sieving residues of the sediments yielding the articulated specimens (see [ 24 ] or [ 18 ] for technical details). The majority of the specimens were thus prepared by ourselves, except Ophiochondrus stelliger , Hemieuryale pustulata and Sigsbeia murrhina for which sets of SEM and digital light images were graciously provided by A. Gondim (see also [ 25 ]), and Ophiolepis superba for which T. Piñeda kindly donated a complete set of images. Our own observations of Ophiosparte gigas were complemented with published images from Martynov [ 17 ].…”

Taxonomic analysis of the genital plates and associated structures in Ophiuroidea (Echinodermata)

“…The type species of Hemieuryalidae, Hemieuryale pustulata von Martens, 1867, has a short abradial GP with a wider distal half and proximal thinner stalk (Gondim et al 2015), more or less comma-shaped. The articular structures consist of a shallow stereom depression and a curved distal groove, matching similar structures on the radial shield; the abradial GP was not found and may be absent (Gondim et al 2015). The radial shield has similar articular structures as in O. longispina.…”