''Admetula gittenbergeri'' 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 ...
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 ...
mollusc
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 esti ...
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 ...
Cancellariidae
Cancellariidae, common name the nutmeg snails or nutmeg shells, are a family of small to medium-large sea snails, marine gastropod mollusks in the clade Neogastropoda. Some of the shells of the species in this family resemble a nutmeg seed.
Di ...
, the nutmeg snails.
[Verhecken A. (2007). ''Revision of the Cancellariidae (Mollusca, Neogastropoda, Cancellarioidea) of the eastern Atlantic (40°N-40°S) and the Mediterranean''. Zoosystema : 29(2): 281–364 p. 286–289](_blank)
Description
The size of the whitish, solid shell varies between 11 mm and 14 mm. 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 ...
is paucispiral with a slightly less than one whorl and shows fine spiral
stria
Stretch marks, also known as striae () or striae distensae, are a form of scarring on the skin with an off-color hue. Over time they may diminish, but will not disappear completely. Striae are caused by tearing of the dermis during periods of r ...
e (stretch marks). The
teleoconch
The gastropod shell is part of the body of a gastropod or snail, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. Some ...
consists of 3.5 whorls with the second and the third whorl showing five spiral bands and 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 ...
with twelve spiral bands. The whorls are axially crossed by twelve and thirteen rounded ribs on the second and third whorls and by ten ribs on the body whorl. The white semicircular
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 opt ...
has a nacreous gloss. The thick outer lip has no inner
lirae. 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 wo ...
shows two folds with a conspicuous tooth close to the
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 ...
. The
umbilicus is closed by a callus. The
periostracum
The periostracum ( ) is a thin, organic coating (or "skin") that is the outermost layer of the shell of many shelled animals, including molluscs and brachiopods. Among molluscs, it is primarily seen in snails and clams, i.e. in gastropods and ...
is covered with thin, short hairs between the spiral cords.
Distribution
This species is found in the Atlantic Ocean off
Mauritania
Mauritania (; ar, موريتانيا, ', french: Mauritanie; Berber: ''Agawej'' or ''Cengit''; Pulaar: ''Moritani''; Wolof: ''Gànnaar''; Soninke:), officially the Islamic Republic of Mauritania ( ar, الجمهورية الإسلامية ...
.
References
* Verhecken A. 2002. ''Atlantic bathyal Cancellariidae (Neogastropoda: Cancellarioidea): additional data, and description of a new species''. Journal of Conchology 37(5): 505–514
* Hemmen J. (2007). ''Recent Cancellariidae''. Wiesbaden, 428pp
* Bouchet, P.; Fontaine, B. (2009). ''List of new marine species described between 2002 and 2006''. Census of Marine Life.
External links
*
Cancellariidae
Gastropods described in 2002
{{cancellariidae-stub