@article {6507, title = {DNA barcoding echinoderms from the East Coast of South Africa. The challenge to maintain DNA data connected with taxonomy}, journal = {PLoS ONE}, volume = {17}, year = {2022}, month = {Oct-10-2022}, pages = {e0270321}, abstract = {

Echinoderms are marine water invertebrates that are represented by more than 7000 extant species, grouped in five classes and showing diverse morphologies (starfish, sea lilies, feather stars, sea urchins, sea cucumbers, brittle and basket stars). In an effort to further study their diversity, DNA barcodes (DNA fragments of the 5\’ end of the cytochrome c oxidase subunit I gene, COI) have been used to complement morphological examination in identifying evolutionary lineages. Although divergent clusters of COI sequences were reported to generally match morphological species delineations, they also revealed some discrepancies, suggesting overlooked species, ecophenotypic variation or multiple COI lineages within one species. Here, we sequenced COI fragments of 312 shallow-water echinoderms of the East Coast of South Africa (KwaZulu-Natal Province) and compared morphological identifications with species delimitations obtained with four methods that are exclusively based on COI sequences. We identified a total of 103 morphospecies including 18 that did not exactly match described species. We also report 46 COI sequences that showed large divergences (\>5\% p-distances) with those available to date and publish the first COI sequences for 30 species. Our analyses also identified discordances between morphological identifications and COI-based species delimitations for a considerable proportion of the morphospecies studied here (49/103). For most of them, further investigation is necessary to keep a sound connection between taxonomy and the growing importance of DNA-based research.

}, issn = {1932-6203}, doi = {10.1371/journal.pone.0270321}, url = {http://dx.doi.org/10.1371/journal.pone.0270321}, author = {Sonet, Gontran and Smitz, Nathalie and Vangestel, Carl and Samyn, Yves}, editor = {Chiang, Tzen-Yuh} } @article {6492, title = {Exploring the use of micro-computed tomography (micro-CT) in the taxonomy of sea cucumbers: a case-study on the gravel sea cucumber Neopentadactyla mixta ({\"O}stergren, 1898) (Echinodermata, Holothuroidea, Phyllophoridae)}, journal = {Zookeys}, volume = {1054}, year = {2021}, month = {Aug-04-2021}, pages = {173-184}, abstract = {

Sea cucumber taxonomy and systematics has in the past heavily relied on gross external and internal anatomy, ossicle assemblage in different tissues, and molecular characterisation, with coloration, habitat, and geographical and bathymethric distribution also considered important parameters. In the present paper, we made these observations and techniques in detail and complemented them with the novel technique of micro-computed tomography of the calcareous ring. We investigated a single European species, the so-called gravel sea cucumber, Neopentadactyla mixta (\Östergren, 1898), using recently collected material from the Chausey Islands, Normandy, France. We redescribed the species, illustrated its ossicle assemblage through scanning electron microscopy, and visualised the calcareous ring through stacking photography and through micro-CT scanning. Additionally, a DNA fragment of 955 base pairs of the 18S ribosomal RNA gene was sequenced from one specimen, which showed a high similarity with the only sequence of N. mixta publicly available. We completed this integrative study by providing a detailed distribution of the occurrence of N. mixta based on published, verifiable accounts.

}, issn = {1313-2970, 1313-2989}, doi = {10.3897/zookeys.1054.67088}, url = {http://dx.doi.org/10.3897/zookeys.1054.67088}, author = {Samyn, Yves and Sonet, Gontran and d{\textquoteright}Acoz, Cedric d{\textquoteright}Udekem} }