著者

岡野 元哉 和田 年史

出版者

日本貝類学会

雑誌

Venus (Journal of the Malacological Society of Japan) (ISSN:13482955)

巻号頁・発行日

vol.70, no.1, pp.58-62, 2012

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We investigated size structure and reproduction of violet shell <i>Janthina prolongata</i> stranded on the coast of Iwami-cho in eastern part of Tottori Prefecture, southwestern Sea of Japan, on 27 September, 2010. Shell length (SL) exhibited a bimodal size distribution with a range of 6.08–40.36 mm. Our results also indicated that individuals of more than 27.4 mm SL laid egg capsules under their bubble raft. Moreover, there was a significant positive correlation between the length of egg capsules and SL. Larger individuals had shrunken and differently colored egg capsules on the forefront of bubble raft, suggesting that <i>J. prolongata</i> might lay egg capsules intermittently.