Spiraxis Cingalensis
   HOME

TheInfoList



OR:

''Spiraxis cingalensis'' is a
species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of air-breathing
land snail A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial molluscs, terrestrial gastropod mollusks that have gastropod shell, shel ...
s, a
terrestrial Terrestrial refers to things related to land or the planet Earth, as opposed to extraterrestrial. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on o ...
pulmonate Pulmonata or pulmonates is an informal group (previously an order, and before that, a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group inclu ...
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 ...
in the family
Spiraxidae Spiraxidae is a family (biology), family of predatory air-breathing land snails, terrestrial molluscs, terrestrial pulmonate gastropods in the superfamily Testacelloidea (according to the Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), taxon ...
. This is a
taxon inquirendum In biological classification, a ''species inquirenda'' is a species of doubtful identity requiring further investigation. The use of the term in English-language biological literature dates back to at least the early nineteenth century. The ter ...
.


Description

The length of the shell attains 14 mm, its diameter 3 mm. (Original description in Latin) The shell is narrowly perforate, subulate-turrite, slender, solid, polished, and finely striated, with numerous minute, closely spaced, wavy spiral striae crossing the surface. The
spire A spire is a tall, slender, pointed structure on top of a roof of a building or tower, especially at the summit of church steeples. A spire may have a square, circular, or polygonal plan, with a roughly conical or pyramidal shape. Spire ...
is elongated, gradually tapering above, with an undetermined
apex The apex is the highest point of something. The word may also refer to: Arts and media Fictional entities * Apex (comics) A-Bomb Abomination Absorbing Man Abraxas Abyss Abyss is the name of two characters appearing in Ameri ...
. The suture is barely impressed and irregular. There are 11 remaining
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 (the apical ones are missing), which are flattened, with 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 ...
rounded at the base. The
aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...
is slightly oblique and elliptical with a notch. The
peristome Peristome (from the Greek language, Greek ''peri'', meaning 'around' or 'about', and ''stoma'', 'mouth') is an anatomical feature that surrounds an opening to an organ or structure. Some plants, fungi, and shelled gastropods have peristomes. In mo ...
is straight and calloused internally at the upper angle. The right margin is arched above, the basal margin thickened, and the columellar margin calloused, slightly expanded, and somewhat reflexed. At its upper end, it is reinforced by a solid, oblique, spiral fold. They were first described in 1863 by British
malacologist Malacology, from Ancient Greek μαλακός (''malakós''), meaning "soft", and λόγος (''lógos''), meaning "study", is the branch of invertebrate zoology that deals with the study of the Mollusca (molluscs or mollusks), the second-largest ...
William Henry Benson.


Distribution

This species is endemic to
Sri Lanka Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...
.


References

{{Taxonbar, from=Q106271909 Spiraxidae Gastropods described in 1863 Gastropods of Sri Lanka Taxa named by William Henry Benson