''Comitas rotundata'' 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
Marine is an adjective meaning of or pertaining to the sea or ocean.
Marine or marines may refer to:
Ocean
* Maritime (disambiguation)
* Marine art
* Marine biology
* Marine debris
* Marine habitats
* Marine life
* Marine pollution
Military
* ...
gastropod mollusc 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 ...
Pseudomelatomidae
Pseudomelatomidae is a family of predatory sea snails, marine gastropods included in the superfamily Conoidea (previously Conacea) and part of the Neogastropoda ( Bouchet & Rocroi, 2005).
In 1995 Kantor elevated the subfamily Pseudomelatominae ...
, the turrids and allies.
[MolluscaBase (2018). Comitas arcana (E. A. Smith, 1899). Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=433330 on 2018-06-06]
Description
The length of the shell attains 25 mm, its diameter 9 mm.
The dark white shell has a fusiform shape, and an acuminate, turreted
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 ...
. It contains about 10
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. The upper portion of the whorl is declining and concave. Below the whorls are angulated and tuberculated at the angles. These rather sharp tubercles number 12 on the
body whorl. The transverse striae upon the upper concave portion of the whorls are finer and less conspicuous than those below the row of tubercles. 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 narrowed in front and measures about ½ the total length. The
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 a little oblique and is callous. The outer
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 tenuous, widely sinuate and prominently arcuate in the middle.
[Melvill J.C. 1899. Notes on the Mollusca of the Arabian Sea, Persian Gulf and Gulf of Oman, mostly dredged by Mr F. W. Townsend, with descriptions of twenty-seven species. ; The Annals and Magazine of Natural History, vol. 4 , s. 7; London, 1899]
Distribution
This marine species occurs off Southwest
India
India, officially the Republic of India ( Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the ...
and the
Andamans
The Andaman Islands () are an archipelago in the northeastern Indian Ocean about southwest off the coasts of Myanmar's Ayeyarwady Region. Together with the Nicobar Islands to their south, the Andamans serve as a maritime boundary between the ...
.
References
E.A. Smith, Illustrations of the Zoology of H.M. Indian Marine Surveying Steamer Investigator. Part I: Mollusca (1897-1908)
External links
*
{{Taxonbar, from=Q3717741
arcana
Arcana may refer to: Music
* Arcana (American band), an American jazz band
* Arcana (Swedish band), a Swedish dark wave band
* Arcana (record label), a French classical record label
* Arcana (album), ''Arcana'' (album), a 2001 album by Edenbridge ...
Gastropods described in 1899