''Microdrillia fastosa'' is a species of

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

, a 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 ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

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.org/ ...

.Bouchet, P. (2015). Microdrillia fastosa (Hedley, 1907). In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=848229 on 2016-03-15

Description

The height of the shell attains 5 mm, its width 1.9 mm. (Original description) The shell is small, rather solid, slender and has a fusiform shape. It contains 8½

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). In nature File:Photograph and axial plane floral diagra ...

s of which six form 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 " ...

. The colour of adult whorls is straw yellow, the protoconch cinnamon brown.

Sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

: running below the suture the adult whorls have a spiral thread which ascends into the protoconch for two whorls. This is followed by a broad concave fasciole, margined in turn by a sharp projecting keel which determines an angle in the contour of the shell. Halfway between the major keel and the suture runs a smaller keel. On the

body whorl The body whorl is part of the morphology (biology), morphology of the gastropod shell, 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 ...

there are about fourteen spirals, gradually diminishing anteriorly, below the major keel. The fasciole is ornamented by spaced, delicate, concave riblets. Fine arcuate growth lines appear in the interstices of the spiral keels. In the protoconch, the first wliorl and a half are small, rounded, and spirally striate. The rest protrude medially, and are crossed by fine sharp radial riblets, which on the last whorl number twenty-two. Their interstices are latticed by spiral threads.

Distribution

This marine species is endemic to

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

and occurs off

New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...

References

* Hedley, C. 1907. ''The results of deep sea investigation in the Tasman Sea. Mollusca from eighty fathoms off Narrabeen''. Records of the Australian Museum 6: 283-304 * Hedley, C. 1922. ''A revision of the Australian Turridae''. Records of the Australian Museum 13(6): 213–359, pls 42-56 * Powell A. W. B. (1966). ''The molluscan families Speightiidae and Turridae. An evaluation of the valid taxa both Recent and fossil, with lists of characteristic species''. Bulletin of the Auckland Institute and Museum 5: 1-184 * 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.

External links

Bouchet P., Kantor Yu.I., Sysoev A. & Puillandre N. (2011) A new operational classification of the Conoidea. Journal of Molluscan Studies 77: 273-308
* {{DEFAULTSORT:Microdrillia Fastosa fastosa Gastropods of Australia Gastropods described in 1907 Endemic fauna of Australia Fauna of New South Wales