Modern alongside traditional taxonomy-Integrative systematics of the genera Gymnangium Hincks, 1874 and Taxella Allman, 1874 (Hydrozoa, Aglaopheniidae)

Marta Ronowicz (1) , Emilie Boissin (2, 3) , Bautisse Postaire (4, 3, 5) , Chloé A.-F. Annie-France Bourmaud (3, 4) , Nicole Gravier-Bonnet (3, 4) , P. Schuchert (6)

1 Department of Marine Ecology
2 CRIOBE - Centre de recherches insulaires et observatoire de l'environnement
3 LabEX CORAIL - Laboratoire d'Excellence CORAIL
4 ENTROPIE [Réunion] - Ecologie marine tropicale dans les Océans Pacifique et Indien
5 IMBE - Institut méditerranéen de biodiversité et d'écologie marine et continentale
6 Natural History Museum [Geneva]

We studied the diversity within the former genus Gymnangium in the South West Indian Ocean by using an integrative approach of both traditional (morphology-based) and modern molecular taxonomy. Nine species were recorded in the material collected. A total of 97 16S mitochondrial DNA sequences and 54 Calmodulin nuclear sequences from eight Gymnangium/Taxella species were analyzed. We found both morphological and molecular differences in the studied Gymnangium species that make it necessary to split the genus. It is proposed to revalidate the genus Taxella which is currently regarded as a synonym of Gymnangium. Two species of the genus Taxella (T. eximia and T. gracilicaulis), until now regarded as distinct species based on morphological characteristics, cluster together in one phylogenetic clade. Possible explanations are discussed. Two species from Madagascar new to science are herein described and rare species from the Indian Ocean islands are re-described.

Keywords: Phylogenetic analysis; Teeth; Phylogenetics; Taxonomy; Indian Ocean; Internodes; Principal component analysis; New species reports

Domains: Invertebrate Zoology; Systematics, Phylogenetics and taxonomy; Genomics [q-bio.GN]

Marta Ronowicz, Emilie Boissin, Bautisse Postaire, Chloé A.-F. Annie-France Bourmaud, Nicole Gravier-Bonnet, et al.. Modern alongside traditional taxonomy-Integrative systematics of the genera Gymnangium Hincks, 1874 and Taxella Allman, 1874 (Hydrozoa, Aglaopheniidae). PLoS ONE, 2017, 12 (4), pp.e0174244. ⟨10.1371/journal.pone.0174244⟩. ⟨hal-01564043⟩