''Crosseola inverta'' is a species of small

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 ...

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

, a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

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 ...

mollusc 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 esti ...

in the family

Conradiidae Conradiidae is a taxonomic family (created in 1987 by Golikov & Starobogatov) of very small sea snails, marine gastropod molluscs or micromolluscs. These genera were previously included in the polyphyletic family Skeneidae. They belong with ...

.MolluscaBase (2019). MolluscaBase. Crosseola inverta (Hedley, 1907). Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=1381388 on 2020-01-27

Description

(Original description by Charles Hedley) The height of the shell measures 2.45 mm, its diameter 2.65 mm. The very solid, milk-white shell has a biconical shape. The base of the shell is produced, much exceeding the spire, which is low and gradated. The shell contains four

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral ...

s, the first minute, unsculptured, the others rapidly increasing in size, parted by channelled sutures. Sculpture : the upper whorls carry three thick, elevated, spiral ribs, divided by broad, deep grooves. These vanish on the

body whorl The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the b ...

, which is entirely covered by dense, microscopic spirals so crossed by radials as to give the effect of fine punctures over the whole surface. The basal funicle is massive, coiled on the body whorl like a subsidiary whorl, far extended anteriorly, its truncate extremity excavate. A small perforation occurs below the subcircular aperture in the base of the funicle. The simple outer lip simple is inner reflected over the umbilicus. The umbilicus has superiorly a narrow spiral perforation, inferiorly a trough hollowed between the columella and the funicle. Charles Hedley, The Mollusca of Mast Head Reef, Capricorn Group, Queensland. Part II; Proceedings of the Linnean Society of New South Wales v. 32 (1907)
/ref>

Distribution

This marine species is endemic to Australia. It occurs off Queensland.

References

* Cotton, B.C. 1959. ''South Australian Mollusca. Archaeogastropoda''. Handbook of the Flora and Fauna of South Australia. Adelaide : South Australian Government Printer 449 pp. * Rubio F. & Rolán E. (2019). New species of Conradiidae Golikov & Starobogatov, 1987 (= Crosseolidae Hickman, 2013) (Gastropoda: Trochoidea) from the Tropical Indo-Pacific II. The genus Crosseola and the description of Crossolida n. gen. Novapex. 20(3): 49-91

External links

World Register of Marine Species

Hedley, C. 1907. ''Mollusca of Mast Head Reef, Queensland. Part 2''. Proceedings of the Linnean Society of New South Wales 32: 476-513, pls 16-21
{{Taxonbar, from=Q5188544 inverta Gastropods described in 1907