- 著者
- Kakui Keiichi Fujiwara Yoshihiro
- 出版者
- Zoological Society of Japan
- 雑誌
- Zoological Science (ISSN:02890003)
- 巻号頁・発行日
- vol.37, no.4, pp.303-306, 2020-08
- 被引用文献数
- 3
We report on the behavior of a deep-sea tanaidacean, Gigantapseudes sp. (Apseudomorpha: Gigantapseudidae), recorded at the depths of 6446–6447 m by the manned submersible Shinkai 6500. From recordings of at least three individuals walking on the sea floor, we confirm that Gigantapseudes sp. is epibenthic, as previously inferred from leg shape. One individual was recorded entering a hole. All individuals in the videos kept pereopods 4 raised from the seafloor while walking, implying that those legs have a function other than for walking, such as mechano- or chemoreception, or posture control. Our in situ observations of behavior are the first for any deepsea tanaidacean and illustrate the importance of recording high-resolution videos in the deep sea and archiving them for future use. Our identification of Gigantapseudes sp. from video footage provides the first record of this genus from Japanese waters and extends the northern limit of the known generic distribution.
- 著者
- Kakui Keiichi Nomaki Hidetaka Komatsu Hironori Fujiwara Yoshihiro
- 出版者
- Oxford University Press
- 雑誌
- Biological Journal of the Linnean Society (ISSN:00244066)
- 巻号頁・発行日
- vol.131, no.3, pp.566-574, 2020
- 被引用文献数
- 5
Information on the extent, diversity and connectivity of populations is lacking for most deep-sea invertebrates. Species of the order Tanaidacea (Crustacea), one of the most diverse and abundant macrofaunal groups in the deep sea, are benthic, lack a planktonic larval stage, and thus would be expected to have narrow distributional ranges. However, with molecular evidence from the COI gene, we show here that the deep-sea tanaidacean Carpoapseudes spinigena has a distributional range spanning at least 3700 km, from off northern Japan to the south-eastern Bering Sea. Living individuals found in a sediment core indicated that the species is a sedentary burrower. COI analyses revealed a low level of genetic diversity overall, and low differentiation (p-distance, 0.2–0.8%) between the Japan and Bering Sea populations. One hypothesis to explain the low genetic diversity over a broad region is that the Japan population was founded by individuals transported by ocean currents from the Bering Sea. However, due to limited data, other explanations cannot be ruled out. Our results indicate that continued sampling is of fundamental importance to understanding how genetic and taxonomic diversity originate and are maintained in the deep sea.
- 著者
- Fujikura Katsunori Fujiwara Yoshihiro Kawato Masaru
- 出版者
- 社団法人日本動物学会
- 雑誌
- Zoological science (ISSN:02890003)
- 巻号頁・発行日
- vol.23, no.8, pp.733-740, 2006-08-25
- 被引用文献数
- 66
A new whale-bone-eating polychaete species of the genus Osedax was found on sperm whale carcasses submerged off Cape Nomamisaki, Kyushu, Japan, at a depth of approximately 200m. The new species, Osedax japonicus, is the fourth known species of the genus Osedax and the first species from the western Pacific. Female O. japonicus specimens (1) form dense clusters on whale carcasses; (2) have a body composed of crown, trunk, and root structure; (3) lack a digestive tract; and (4) have bacterium-like particles in the tissue of the root structure. Osedax japonicus shares all these characteristics with O. rubiplumus and O. frankpressi, and items (1) to (3) with O. mucofloris. Osedax japonicus is easily distinguished from the other three known species by oviduct morphology, body length, and palp coloration in females. No males of O. japonicus have yet been found.