Phylogenomic analyses of mud dragons (Kinorhyncha)

• DOI: 10.1016/j.ympev.2021.107375
• Publication Date: 2021-12-21T07:23:46Z
• Authors: Maria Herranz; Josefin Stiller; Katrine Worsaae; Martin V. Sørensen
• Keywords: Kinorhynchs; 0106 biological sciences; Nematoda; Evolution; Meiofauna; 01 natural sciences; Segmentation; Animals; 14. Life underwater; Transcriptome; Arthropods; Phylogeny

Mud dragons (Kinorhyncha) are microscopic invertebrates, inhabiting marine sediments across the globe from intertidal to hadal depths. They segmented, moulting animals like arthropods, but grouping with unsegmented priapulans and loriciferans within Ecdysozoa. There more than 300 species of kinorhynchs described 31 genera 11 families, however, their evolutionary relationships have so far only been investigated using morphology a few molecular markers. Here we aim resolve classification major clades Kinorhyncha transcriptomic data. In addition, wish revisit position three indistinctly aberrant in order reconstruct evolution distinct segmentation group. We conducted phylogenomic analysis including 21 kinorhynch transcriptomes (of which 18 new) representing 15 genera, seven outgroups priapulan, loriciferan, nematode nematomorph transcriptomes. Results show congruent robust tree that supports division into two clades: Cyclorhagida Allomalorhagida. is composed subclades: Xenosomata, Kentrorhagata comb. nov. (including Zelinkaderes) Echinorhagata. Allomalorhagida Pycnophyidae Anomoirhaga nom. accommodates Cateria (previously nested Cyclorhagida) Franciscideres together five additional genera. The distant derived positions Zelinkaderes, suggest less trunk evolved convergently, among stem groups.