TY - JOUR
T1 - Taxonomy, genetic diversity, and phylogeny of the Antarctic mud dragon, Polacanthoderes (Kinorhyncha: Echinorhagata: Echinoderidae)
AU - Yamasaki, Hiroshi
AU - Fujimoto, Shinta
AU - Tanaka, Hayato
AU - Shimada, Daisuke
AU - Ito, Masato
AU - Tokuda, Yuki
AU - Tsujimoto, Megumu
N1 - Funding Information:
Specimens for scanning electron microscopy (SEM) were transferred to dehydrate ethanol, immersed in 100% t-butyl alcohol, freeze-dried, mounted on aluminium stubs, sputter-coated with gold-palladium, and observed with a Hitachi SU3500 scanning electron microscope at Center for Advanced Instrumental and Educational Supports, Faculty of Agriculture, Kyushu University (Fukuoka, Japan).The BI and ML analyses produced trees of very similar topology, hence we show the ML tree with nodal support (ML bootstrap values (BS) and BI posterior probability (PP)) in Fig. 10. The resulted topology is mostly congruent with those of the previous phylogenetic and phylogenomic studies of kinorhynchs (Dal Zotto et al., 2013; Herranz et al., 2022; Sørensen et al., 2015; Yamasaki et al., 2013). The only remarkable difference among the new and previous results is the position of the clade Paracentrophyes + Franciscideridae (Franciscideres and Gracilideres): it is represented as the sister clade of Pycnophyidae in the analyses based on the 18S and 28S gene sequences (Yamasaki et al., 2013; Sørensen et al., 2015; this study), whereas it composes the Anomoirhaga clade together with Dracoderes and Cateria in the phylogenomic analyses (Herranz et al., 2022). Aside from the difference between this and previous analyses found in the Allomalorhagida clade, the relationships of cyclorhagids (Echinorhagata, Kentrorhagata, and Xenosomata) are consistent throughout all analyses.We thank Dr Satoshi Imura and Dr Takeshi Tamura (National Institute of Polar Research, Research Organization of Information and Systems) and Dr Kay I Ohshima (Institute of Low Temperature Science, Hokkaido University) for their sincere support throughout this study; the officer, crew, and scientists on board the icebreaker Shirase for their assistance in the field operations and sample collections; Mr Koga Nakada (Kyushu University) and Mr Kaoru Kurosawa (Kyushu University) for their help in extracting meiofauna from the sediment samples; Dr Birger Neuhaus (Museum für Naturkunde Berlin, Germany) for his help in observing the type material of Polacanthoderes martinezi; Center for Advanced Instrumental and Educational Supports, Faculty of Agriculture (Kyushu University) for making facilities for SEM observation available. Sample collections during the JARE expeditions were supported by several KAKENHI Grants (17H01157, 17H01615, 17H04710, 17H06318, 17H06321, 18H01329, 18K13649, 19H00728, and 21H01201) from the Japan Society for the Promotion of Science, the Science Program of JARE as Prioritized Research Project (ROBOTICA), National Institute of Polar Research (NIPR) through Project Research KP-303 and KP-309, the Center for the Promotion of Integrated Sciences of SOKENDAI, and the Joint Research Program of the Institute of Low Temperature Science, Hokkaido University. After the sample collections, meiofaunal extraction, observation, and molecular work were carried out with a KAKENHI Grant (20H04974) to MT and another KAKENHI Grant (20K22670) to HY from the Japan Society for the Promotion of Science.
Funding Information:
We thank Dr Satoshi Imura and Dr Takeshi Tamura ( National Institute of Polar Research , Research Organization of Information and Systems ) and Dr Kay I Ohshima (Institute of Low Temperature Science, Hokkaido University ) for their sincere support throughout this study; the officer, crew, and scientists on board the icebreaker Shirase for their assistance in the field operations and sample collections; Mr Koga Nakada ( Kyushu University ) and Mr Kaoru Kurosawa ( Kyushu University ) for their help in extracting meiofauna from the sediment samples; Dr Birger Neuhaus (Museum für Naturkunde Berlin, Germany) for his help in observing the type material of Polacanthoderes martinezi; Center for Advanced Instrumental and Educational Supports, Faculty of Agriculture ( Kyushu University ) for making facilities for SEM observation available. Sample collections during the JARE expeditions were supported by several KAKENHI Grants (17H01157, 17H01615, 17H04710, 17H06318, 17H06321, 18H01329, 18K13649, 19H00728, and 21H01201) from the Japan Society for the Promotion of Science , the Science Program of JARE as Prioritized Research Project (ROBOTICA), National Institute of Polar Research ( NIPR ) through Project Research KP-303 and KP-309, the Center for the Promotion of Integrated Sciences of SOKENDAI, and the Joint Research Program of the Institute of Low Temperature Science, Hokkaido University . After the sample collections, meiofaunal extraction, observation, and molecular work were carried out with a KAKENHI Grant (20H04974) to MT and another KAKENHI Grant (20K22670) to HY from the Japan Society for the Promotion of Science .
Publisher Copyright:
© 2022 Elsevier GmbH
PY - 2022/11
Y1 - 2022/11
N2 - A new species Polacanthoderes shiraseae sp. nov. from three Antarctic regions (off Cape Darnley, off Totten Glacier, and in Lützow-Holm Bay) is described. In addition, type species of Polacanthoderes, Polacanthoderes martinezi, is redescribed. The new species is distinguished from P. martinezi by the presence of conspicuously thick lateroventral acicular spines on segments 8 and 9 and the presence of sublateral small acicular spines on segment 7. Both P. martinezi and P. shiraseae sp. nov. occasionally show intraspecific morphological variations in the position of some small acicular spines. The K2P genetic distances based on the mitochondrial cytochrome c oxidase subunit 1 gene sequences in P. shiraseae sp. nov. are 0–1.5%, equivalent to those in other echinoderid species. Phylogenetic analyses of Polacanthoderes based on the nuclear 18S rRNA and 28S rRNA gene sequences support the inclusion of the genus in Echinorhagata/Echinoderidae and suggest that the genus represents the most basal group of this order/family.
AB - A new species Polacanthoderes shiraseae sp. nov. from three Antarctic regions (off Cape Darnley, off Totten Glacier, and in Lützow-Holm Bay) is described. In addition, type species of Polacanthoderes, Polacanthoderes martinezi, is redescribed. The new species is distinguished from P. martinezi by the presence of conspicuously thick lateroventral acicular spines on segments 8 and 9 and the presence of sublateral small acicular spines on segment 7. Both P. martinezi and P. shiraseae sp. nov. occasionally show intraspecific morphological variations in the position of some small acicular spines. The K2P genetic distances based on the mitochondrial cytochrome c oxidase subunit 1 gene sequences in P. shiraseae sp. nov. are 0–1.5%, equivalent to those in other echinoderid species. Phylogenetic analyses of Polacanthoderes based on the nuclear 18S rRNA and 28S rRNA gene sequences support the inclusion of the genus in Echinorhagata/Echinoderidae and suggest that the genus represents the most basal group of this order/family.
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U2 - 10.1016/j.jcz.2022.09.003
DO - 10.1016/j.jcz.2022.09.003
M3 - Article
AN - SCOPUS:85138656207
SN - 0044-5231
VL - 301
SP - 42
EP - 58
JO - Zoologischer Anzeiger
JF - Zoologischer Anzeiger
ER -