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''Ifremeria nautilei'' is a species of large, deepwater hydrothermal vent sea snail, a marine gastropod mollusk in the family Provannidae, and the only species in the genus ''Ifremeria''. This species lives in the South Pacific Ocean Other species in the family Provannidae live in similar deepwater hydrothermal vent habitats. As is the case in species in the genus ''Alviniconcha'', the tissues of ''Ifremeria nautilei'' contain symbiotic bacteria which live on the sulfur from the vents, and the snails derive their nutrition from this symbiosis. This species is particularly notable because the female snails have a brood pouch on the foot, and because they release a gastropod larval form which had never been observed and described before until 2008. ==Description== ''Ifremeria nautilei'' attains a maximum dimension of 85 mm, which is larger than other abyssochroids (length usually under 20 mm). This species hosts symbiotic chemoautotrophic bacteria that oxidize sulfur from hydrothermal vents. This arrangement enables it to satisfy most of its metabolic requirements. This species is unique among the others in this superfamily in two respects. Firstly females of the species possess a brood pouch (a metapodial pedal gland) in the foot. Secondly the species releases unusual, previously unknown, uniformly ciliated lecithotrophic larvae, which are now known as Warén's larvae. These are free swimming larvae which swim with their posterior end forwards. They metamorphose after 15 days into shelled veliger larvae, the more usual form. Warén's larva (named after Anders Warén of the Swedish Museum of Natural History), is the first new gastropod larval form to have been described in more than 100 years.〔Kaim, A., R.G. Jenkins, and A. Warén. 2008, ''Provannid and provannid-like gastropods from the late Cretaceous cold seeps of Hokkaido (Japan) and the fossil record of the Provannidae (Gastropoda, Abyssochrysoidea).'' Zool. J. Linn. Soc. 154: 421-436〕〔KYLE C. REYNOLDS, HIROMI WATANABE, ELLEN E. STRONG, TAKENORI SASAKI, KATSUYUKI UEMATSU, HIROSHI MIYAKE, SHIGEAKI KOJIMA, YOHEY SUZUKI, KATSUNORI FUJIKURA, STACY KIM and CRAIG M. YOUNG, ''New Molluscan Larval Form: Brooding and Development in a Hydrothermal Vent Gastropod, ''Ifremeria nautilei'' (Provannidae)''; Biological Bulletin, Vol. 219, No. 1 (August 2010), pp. 7-11〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ifremeria nautilei」の詳細全文を読む スポンサード リンク
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