''Filodrillia mucronata'' 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 mucronata Hedley, 1922. In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=433811 on 2016-03-06

Description

The length of the shell attains 9.5 mm, its width 3.5 mm. (Original description) The elongate shell has a fusiform shape. Its colour is uniform ivory-yellow. It contains seven

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, of which two compose 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 ...

. Sculpture:—The radial sculpture is absent. On the shoulder a sharp angle is defined by a prominent cord, above which six fine and closely packed threads occupy the fasciole area. Below this the cords as they descend become smaller and closer, those in the hollow of the base being the most crowded. There are twenty-two such cords 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 ...

, and three or four on the upper whorls. The right insertion of the aperture :mounts slightly above the plane of the suture. The sinus shows a large U-shaped spout, below which is an incipient varix. Beyond the latter the free limb of the outer lip bends inwards. Within this lip are sometimes a few entering plications. The inner lip shows a sheet of callus, thin above, but with a thickened margin below. The

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 ...

is short, expanding, and open. Hedley, Charles (1920), A revision of the Australian Turridae; Records of the Australian Museum, vol. XIII nr. 6, Sydney
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Distribution

This marine species is endemic to Australia and occurs off New South Wales.

References

* Laseron, C. 1954. ''Revision of the New South Wales Turridae (Mollusca).'' Australian Zoological Handbook. Sydney : Royal Zoological Society of New South Wales 1-56, pls 1-12. {{DEFAULTSORT:Filodrillia Mucronata mucronata Gastropods of Australia Gastropods described in 1922