''Filodrillia lacteola'' is a species of

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 in the family

Borsoniidae Borsoniidae is a monophyletic family of small to medium-sized sea snails, marine gastropod mollusks in the superfamily Conoidea.Bouchet, P. (2011). Borsoniidae. Accessed through: World Register of Marine Species at http://www.marinespecies.o ...

.WoRMS (2015). Filodrillia crebrespirata (Verco, 1909). In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=435268 on 2016-03-07

Description

The length of the shell attains 4.8 mm, its width 2.1 mm. (Original description) The thin shell is translucent-white. It contains 6

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, including the

protoconch A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called ...

of 2 smooth convex whorls. The whorls on the spire are convex. The suture is simple, narrowly margined. 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 ...

is roundly contracted at the base. The aperture is elongate-oval, opening widely into a short

siphonal canal The siphonal canal is an anatomical feature of the shells of certain groups of sea snails within the clade Neogastropoda. Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is ...

. The outer lip is simple, thin, crenulated outside; with a deep rounded posterior sinus near the suture, having a thickened and slightly erect edge, with a shallow excavation anteriorly where it is pinched to form the canal. The inner lip is complete, applied, glazed, thin, thickened at the back to meet the margin of the sinus. The columella is nearly straight. The thin spirals number seven in the penultimate whorl and twenty in the body whorl. Faint accremental striae minutely roughen the sculpture.Verco, J.C. 1909. ''Notes on South Australian marine Mollusca with descriptions of new species. Part XII.'' Transactions of the Royal Society of South Australia 33: 293-342
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Distribution

This marine species is endemic to Australia and occurs off South Australia, Tasmania and Victoria.

References

Hedley, C. 1922. A revision of the Australian Turridae. Records of the Australian Museum 13(6): 213-359, pls 42-56
* May, W.L. 1923. ''An Illustrated Index of Tasmanian Shells: with 47 plates and 1052 species.'' Hobart : Government Printer 100 pp. {{Taxonbar, from=Q10282344 lacteola Gastropods of Australia Gastropods described in 1909