Julia is a genus of minute sea snails, marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

s or

micromollusk A micromollusc is a shelled mollusc which is extremely small, even at full adult size. The word is usually, but not exclusively, applied to marine molluscs, although in addition, numerous species of land snails and freshwater molluscs also ...

s in the superfamily Oxynooidea. ''Julia'' is the

type genus In biological taxonomy, the type genus (''genus typica'') is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearin ...

of the family Juliidae.

Description

As Tryon (1884) Tryon G. W. Jr. (1884)
''Structural and systematic conchology: an introduction to the study of the Mollusca. Volume III''
Philadelphia, published by the author
p. 267
wrote in his description of the genus ''Julia'': the shell is oblong, thick, and cordiform. The valves are closed, the margins entire and the valves are inequilateral. The lunule is deep circular, projecting into the interior of the right

valve A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or Slurry, slurries) by opening, closing, or partially obstructing various passageways. Valves are technically Pip ...

, the left valve is in the same place furnished with dentiform tubercles. The hinge line is simple and arched. The

ligament A ligament is a type of fibrous connective tissue in the body that connects bones to other bones. It also connects flight feathers to bones, in dinosaurs and birds. All 30,000 species of amniotes (land animals with internal bones) have liga ...

is external and narrow. There are two muscle scars which are unequal and subcentral. These animals have two valves, and the soft parts can be completely withdrawn inside the shell. de Bruyne R. H. (2004). ''Encyklopedie ulit a lastur''. Rebo Productions, 336 pp., , p. 223. The two valves are usually thin and translucent. The empty valves of the shells of these animals are in some cases green, in other cases brownish-green or yellow, and in yet others, colorless. The species '' Julia zebra'' has shells that are finely striped with brown and blotched with white.

Species

* (recent) '' Julia burni'' Sarma, 1975 * (invalidJensen K. R. (1996). "Phylogenetic systematics and classification of the Sacoglossa (Mollusca, Gastropoda, Opisthobranchia)". ''Philosophical Transactions of the Royal Society London B Biological Sciences'' 351(1335): 91-122. . recent species) '' Julia cornuta'' (De Folin, 1867) * (invalid recent species) '' Julia equatorialis'' Pilsbry & Olsson, 1944 * (recent) '' Julia exquisita'' Gould, 1862 - this species was mentioned in report by the

Challenger expedition The ''Challenger'' expedition of 1872–1876 was a scientific programme that made many discoveries to lay the foundation of oceanography. The expedition was named after the naval vessel that undertook the trip, . The expedition, initiated by W ...

* (recent) '' Julia japonica'' Kuroda & Habe, 1951 * (recent) '' Julia mishimaensis'' Kawaguti & Yamasu, 1982Bolland R. F. (2001)
"Okinawan Opisthobranch of the Week ''Julia exquisita''"
Last change of the page 12 March 2001. * (recent) '' Julia thecaphora'' (Carpenter, 1857) - a probable synonym is '' Julia zebra'' Kawaguti, 1981Kawaguti S. (1981). "A new bivalved gastropod ''Julia zebra''". ''Bulletin of the Kawasaki Paramedical College'' 1: 9-13. * (recent) '' Julia zebra'' Kawaguti 1981

References

External links

{{DEFAULTSORT:Julia (Gastropod) Juliidae