Molecular phylogenies challenge the classification of Polymastiidae (Porifera, Demospongiae) based on morphology

• Published in: Organisms Diversity & Evolution
• Main Authors: Plotkin, Alexander, Voigt, Oliver, Willassen, Endre, Rapp, Hans Tore
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 2016
• Subjects: Phylogeny; Homoplasy; Polymastiidae; CO1; 28S rDNA; European Union; Horizon 2020; Grant Agreement No 679849; Deep-sea Sponge Grounds Ecosystems of the North Atlantic an integrated approach towards their preservation and sustainable exploitation; SponGES; Norway; North Atlantic
• Online Access: https://zenodo.org/record/198316; https://doi.org/10.1007/s13127-016-0301-7

Polymastiidae Gray, 1867 is a worldwide distributed sponge family, which has a great significance for understanding of the demosponge deep phylogeny since the former order Hadromerida Topsent, 1894 has been recently split based on the molecular evidence and a new separate order has been established for the polymastiids. However, molecular data obtained from Polymastiidae so far are scarce, while the phylogenetic reconstruction based on morphology has faced a deficit of characters along with the vagueness of their states. The present study is a phylogenetic reconstruction of Polymastiidae based on novel data on two molecular markers, cytochrome oxidase subunit I and large subunit ribosomal DNA, obtained from a broad set of species. Monophyly of the family and nonmonophyly of four polymastiid genera are revealed, suggesting a high level of homoplasy of morphological characters, which are therefore not an appropriate base for the natural classification of Polymastiidae. Although the presented phylogenies cannot yet provide an alternative classification scheme, several strongly supported clades, which may be used as reference points in future classification, are recovered and three taxonomic actions are proposed: transfer of one species from Radiella to Polymastia Bowerbank, 1862; transfer of three species from Radiella Schmidt, 1870 to Spinularia Gray, 1867; and the consequent abandonment of Radiella. This record in Zenodo includes three Supplementary Material files, available to authorized users also on the Journal's article page. This study was supported by the Norwegian Biodiversity Information Centre (grant to HTR, project number 70184219), the Norwegian Academy of Science and Letters (grant to HTR), the Research Council of Norway (through contract number 179560), and the SponGES project through Horizon 2020, the European Union Framework Program for Research and Innovation (grant agreement No 679849). © The Authors 2016. This article is published with open access at Springerlink.com. This article is ...