2025-06-20 京都大学
お尻からキュビエ管を放出するニセクロナマコとその体内・体表に寄生するセトモノガイ類(イラスト:中野真里)
<関連情報>
- https://www.kyoto-u.ac.jp/ja/research-news/2025-06-20-0
- https://www.kyoto-u.ac.jp/sites/default/files/2025-06/web_2506_Nakano-4df54f5d9570456cc7ab73008f814c32.pdf
- https://bioone.org/journals/zoological-science/volume-42/issue-4/zs250003/Co-Occurrence-of-Gastropods-of-the-Genus-Melanella-Mollusca/10.2108/zs250003.short
中部日本におけるクロナマコHolothuria leucospilotaに寄生するMelanella属(軟体動物門:ウミキュウ科)腹足類の共存:地理的分布と寄生生態への影響 Co-Occurrence of Gastropods of the Genus Melanella (Mollusca: Eulimidae) Parasitizing the Black Sea Cucumber Holothuria leucospilota in Central Japan: Implications for Their Geographic Distribution and Parasitic Ecology
Tomoyuki Nakano, Erina Nishiyama, Tsuyoshi Takano
Zoological Science Published:18 June 2025
DOI:https://doi.org/10.2108/zs250003
Abstract
Snails of the family Eulimidae are parasites of echinoderms in all five extant classes. Despite long years of taxonomic research on Eulimidae in Japan, their local species richness remains to be investigated, and few studies have focused on a eulimid fauna of a certain echinoderm taxon, even if it is a common species. Here, we conducted a comprehensive sampling of Melanella species parasitizing the black sea cucumber Holothuria leucospilota in Shirahama, Wakayama, central Japan. The data used in this study were partly obtained during a summer education program of the Seto Marine Biological Laboratory, Kyoto University. Melanella kuronamako and M. spina parasitized the external surface, and two unidentified species were found inside the host’s body cavity. This study represents the first record of M. spina in Japanese waters and eulimids exploiting the internal habitat of H. leucospilota. Morphological and molecular comparisons between the present four species and other Japanese Melanella specimens suggested that they generally exhibit wide geographic distributions and low host specificity. Additionally, the two species from the body cavity were probably seldom observed in central Japan, as inferred from the accumulated results of the dissection of H. leucospilota through a long-running, annual education program at Shirahama.
