''Anadema macandrewii'' is a

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

of sea snail, a marine gastropod

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 es ...

in the

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

Colloniidae Colloniidae is a family of small sea snails with calcareous opercula, marine gastropod mollusks in the clade Vetigastropoda.MolluscaBase eds. (2020). MolluscaBase. Colloniidae Cossmann, 1917. Accessed through: World Register of Marine Specie ...

Description

The umbilicate, reddish yellow shell has an ovate-conoid, trochiform shape. It is thick, slightly elevated, and below subdepressed. 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. Spires are ...

is obtuse. It contains 5-6 slightly convex

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 flo ...

s that are longitudinally and obliquely striate, spirally granose-lirate. The suture is impressed. The body whorl is obtusely angular at the middle. It shows 16-18 spiral granose lirae. The small granules are close. The

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An ...

is transversely ovate, and silvery within. The operculum is calcareous. The

lip The lips are the visible body part at the mouth of many animals, including humans. Lips are soft, movable, and serve as the opening for food intake and in the articulation of sound and speech. Human lips are a tactile sensory organ, and can be ...

is simple. The narrow

columella Lucius Junius Moderatus Columella (; Arabic: , 4 – ) was a prominent writer on agriculture in the Roman Empire. His ' in twelve volumes has been completely preserved and forms an important source on Roman agriculture, together with the ...

is arcuate and thickened at the base. The deep

umbilicus Umbilicus may refer to: *The navel or belly button *Umbilicus (mollusc), a feature of gastropod, Nautilus and Ammonite shell anatomy * ''Umbilicus'' (plant), a genus of over ninety species of perennial flowering plants *Umbilicus urbis Romae The ...

has a spiral funicle inside. ; co-lor reddish yellow. Its altitude is 11 mm, its diameter 16 mm. The species is characterized by the spiral funicle within the umbilicus.G.W. Tryon (1888), Manual of Conchology X; Academy of Natural Sciences, Philadelphia
(described as ''Leptothyra coelata'')

Distribution

This species occurs in the Indian Ocean off

East Africa East Africa, Eastern Africa, or East of Africa, is the eastern subregion of the African continent. In the United Nations Statistics Division scheme of geographic regions, 10-11-(16*) territories make up Eastern Africa: Due to the histori ...

References

External links

* {{DEFAULTSORT:Anadema Macandrewii Colloniidae Gastropods described in 1868