''Calliotropis ottoi'', common name Otto's spiny margarite, 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 ...

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 ...

Eucyclidae Eucyclidae is a family of gastropods in the superfamily Seguenzioidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). This family has no subfamilies. Genera Genera within the family Eucyclidae include: * '' Amberley ...

Description

The size of the shell varies between 6 mm and 18 mm (1/4 to 3/4-inch). The thin and delicate shell is rather large for the genus; it is whitish, brilliantly iridescent or pearly, externally and internally. It has a broad, conical shape. It is turreted, wider than it is high, with a convex base, and deep umbilicus. The seven

whorls 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 d ...

are much flattened, with the suture scarcely impressed. The upper whorls are coronated by two, and the bodywhorl by three, revolving, strongly nodulous ribs, along which the conical, often acute nodules are very regularly arranged. The first of these rows of nodules is just below the suture. The second is separated from the first by a wide, flat, or slightly concave interspace. The third is not far from the second, and surrounds the periphery, usually corresponding with the line of the suture. The second and third are usually the most elevated. On the base of the shell there are five or six strong, rounded, revolving ribs, part of them usually somewhat nodulous, separated by deep, concave interspaces, rather wider than he rib; one or two additional ones often appear in the umbilical opening, which is funnel-shaped and moderately large, but often partially obstructed by the reflected (turned outwards) edge of the inner

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 ...

. The interspaces between all the ribs are covered with close, slightly raised lines of growth, and usually with traces of a thin

epidermis The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and hypodermis. The epidermis layer provides a barrier to infection from environmental pathogens and regulates the amount of water rele ...

. The large

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 ...

is somewhat quadrangular. The lip is thin. The animal has long tentacles and large black eyes. There are four large lateral

cirri Giovanni Battista Cirri (1 October 1724 – 11 June 1808) was an Italian cellist and composer in the 18th century. Biography Cirri was born in Forlì in the Emilia-Romagna Region of Italy. He had his first musical training with his brother ...

on each side, with a group of four or five small intermediate ones. The snout has a broad, bilobed, crescent-shaped expansion in front. The

odontophore The odontophore is part of the feeding mechanism in molluscs. It is the cartilage which underlies and supports the radula, a ribbon of teeth. The radula is found in every class of molluscs except for the bivalves. The feeding apparatus can be exte ...

has no large lateral tooth between the inner and outer series.Tryon (1889), Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
(described as ''Solariella ottoi'')

Distribution

This species occurs in European waters and in the Northwest Atlantic Ocean.

References

* Pollock, L.W. (1998). ''A practical guide to the marine animals of northeastern North America''. Rutgers University Press. New Brunswick, New Jersey & London. 367 pp. * Vilvens C. (2007) ''New records and new species of Calliotropis from Indo-Pacific''. Novapex 8 (Hors Série 5): 1–72

External links

* {{Taxonbar, from=Q3729924 ottoi Gastropods described in 1844 Taxa named by Rodolfo Amando Philippi