- 著者
- Teruaki Nishikawa Hiroshi Namikawa
- 出版者
- The Japanese Society of Systematic Zoology
- 雑誌
- Species Diversity (ISSN:13421670)
- 巻号頁・発行日
- vol.26, no.1, pp.1-5, 2021-01-01 (Released:2021-01-01)
- 参考文献数
- 13
Overlooked since its establishment, Ascidia sydneiensis protecta Van Name, 1945, originally described as having mantle musculature comprising short parallel fibers restricted to the dorsal margin, compared with musculature along the entire margin (except for a central muscle-free area) found in the so-called “A. sydneiensis group”, is treated as a full species, Ascidia protecta. A detailed examination of the type and non-type specimens of the latter, all collected from the Gulf of California, confirmed the mantle musculature arrangement in the species, as well as revealing several new features (particularly in the alimentary tract), although not supporting a protective function of the anterior tunic to retracted siphons, as suggested in the original description. A comparison of A. protecta was made with congeneric species with similar musculature.
- 著者
- Teruaki Nishikawa Hironori Komatsu Yuichi Kameda Kenichiro Tani
- 出版者
- 日本動物分類学会
- 雑誌
- Species Diversity (ISSN:13421670)
- 巻号頁・発行日
- vol.22, no.1, pp.69-72, 2017-05-25 (Released:2017-05-25)
- 参考文献数
- 19
Two mature specimens of the whale-fall lancelet Asymmetron inferum Nishikawa, 2004, were collected in 2016 from reducing gravel bottom near a hydrothermal vent, 196 m deep, at Oomuro Hole of Oomuro-dashi submarine volcano in the Izu Islands, Pacific coast of Japan by using the ROV Hyper-Dolphin during the RV Shinsei-maru KS-16-6 cruise of JAMSTEC. This species has so far been known exclusively from whale-fall communities off Cape Nomamisaki, SW Kyushu, Japan, 219–254 m deep. The new find suggests the dispersal stepping-stone hypothesis of whale-fall communities for the origin of vent and/or seep fauna.