''Microdrillia fastosa'' 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 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 e ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

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 ...

.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). Whorls in nature File:Photograph and axial plane floral ...

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 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 ...

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 Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

and occurs off

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

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