''Ifremeria nautilei'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of large, deepwater

hydrothermal vent A hydrothermal vent is a fissure on the seabed from which geothermally heated water discharges. They are commonly found near volcanically active places, areas where tectonic plates are moving apart at mid-ocean ridges, ocean basins, and hotspot ...

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

, a marine

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Provannidae Provannidae is a family of deep water sea snails, marine gastropod mollusks in the superfmaily Abyssochrysoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005 and updated in 2008 by Kaim et al.). MolluscaBase eds. (2021) ...

, 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 Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...

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 A Chemotroph is an organism that obtains energy by the oxidation of electron donors in their environments. These molecules can be organic ( chemoorganotrophs) or inorganic (chemolithotrophs). The chemotroph designation is in contrast to phototro ...

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 Metapodials are long bones of the hand (metacarpals) and feet (metatarsal The metatarsal bones, or metatarsus, are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. ...

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 The Swedish Museum of Natural History ( sv, Naturhistoriska riksmuseet, literally, the National Museum of Natural History), in Stockholm, is one of two major museums of natural history in Sweden, the other one being located in Gothenburg. The ...

), is the first new gastropod larval form to have been described in more than 100 years.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

Distribution

This species occurs at depths between 1,700 m and 2,900 m, in hydrothermal vents and

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ex ...

cold seeps in the Valufa Ridge, which is southeast of

Fiji Fiji ( , ,; fj, Viti, ; Fiji Hindi: फ़िजी, ''Fijī''), officially the Republic of Fiji, is an island country in Melanesia, part of Oceania in the South Pacific Ocean. It lies about north-northeast of New Zealand. Fiji consists ...

, in the South Pacific Ocean.

References

External links

* * Desbruyères D., Segonzac M. & Bright M. (eds) (2006). ''Handbook of Deep-sea Hydrothermal Vent Fauna''. Second Edition Denisia 18: 1–544. (Copepods 316–355), (Polychaeta 183–296). * Osca D., Templado J. & Zardoya R. (2014). "The mitochondrial genome of ''Ifremeria nautilei'' and the phylogenetic position of the enigmatic deep-sea Abyssochrysoidea (Mollusca: Gastropoda)". ''Gene'' 547: 257–266. * Suzuki Y., Kojima S., Watanabe H., Suzuki M., Tsuchida S., et al. (2006). "Single host and symbiont lineages of hydrothermal vent gastropods, ''Ifremeria nautilei'' (Provannidae): biogeography and evolution". ''Marine Ecology Progress Series'' 315: 167–175. . * Windoffer & Giere (1997). "Symbiosis of the Hydrothermal Vent Gastropod ''Ifremeria nautilei'' (Provannidae) with Endobacteria – Structural analyses and ecological considerations". ''The Biological Bulletin'' 193
381
��392. {{DEFAULTSORT:Ifremeria Nautilei Provannidae Gastropods described in 1991