''Pleurotomella aculeata'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

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 ...

Raphitomidae Raphitomidae is a family of small to medium-sized sea snails, marine gastropod mollusks in the superfamily Conoidea.Bouchet P. & Rocroi J.-P. (Ed.) (2005). "Classification and nomenclator of gastropod families". ''Malacologia'' 47(1-2). . 39 ...

.MolluscaBase (2019). Pleurotomella aculeata (Webster, 1906). Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=599025 on 2019-02-03

Description

The length of the shell attains 6 mm, its diameter 3.3 mm. (Original description) The shell is buff-coloured, lighter towards the apex and

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 ...

. It contains five

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 a reticulated

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 1¼ whorl. The

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 ...

: Longitudinally and slightly diagonally ribbed, the ribs crossed by two strong spiral keels. The ribs and keels are about equal in strength, the intersections forming sharp points. 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 ...

has upon the base four additional keels, the space between the two peripheral keels and the four on the base being greater than that between any other two. A fine thread is visible in this wide space, there is also a duplication of the posterior keel. The body whorl has about twelve ribs. The sutures of the early whorls are sharp, those of the latter are concavely round. The columella descends vertically from the body whorl. The siphonal canal, which is straight, has about eight faint striations. The space between the suture and the first spiral keel contains the anal fasciole. Under magnification one can see faint radial striations between the keels, also the reticulation of the protoconch. The sinus of the type is so little damaged that to draw it perfect can scarcely be called reconstruction. Webster, W.H. (1906) ''Results of dredging on the continental shelf of New Zealand''. Transactions and Proceedings of the New Zealand Institute, 38, 305–316, pl. 38
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Distribution

This marine species is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to New Zealand and occurs off Northland

References

* Powell, A.W.B. 1979 ''New Zealand Mollusca: Marine, Land and Freshwater Shells'', Collins, Auckland

External links

Spencer H.G., Willan R.C., Marshall B.A. & Murray T.J. (2011). Checklist of the Recent Mollusca Recorded from the New Zealand Exclusive Economic Zone
*
Beu, A.G. 2011 ''Marine Molluscs of oxygen isotope stages of the last 2 million years in New Zealand. Part 4. Gastropoda (Ptenoglossa, Neogastropoda, Heterobranchia)''. Journal of the Royal Society of New Zealand 41, 1–153
{{DEFAULTSORT:Pleurotomella Aculeata

aculeata Aculeata is a subclade of Hymenoptera containing ants, bees, and stinging wasps. The name is a reference to the defining feature of the group, which is the modification of the ovipositor into a stinger. However, many members of the group cannot ...

Gastropods described in 1906 Gastropods of New Zealand