''Margarites costalis'',

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...

the boreal rosy margarite or the northern ridged margarite, 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), ...

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

, a marine

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 ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Margaritidae Margaritidae is a family of small sea snails, marine gastropod mollusks in the superfamily Trochoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).Bouchet, P. (2012). Margaritidae. Accessed through: World Register o ...

. ;Subspecies: * ''Margarites costalis baxteri'' J. H. McLean, 1995 * ''Margarites costalis costalis'' (Gould, 1841)

Description

The size of the shell varies between 5 mm and 25 mm. It is a conical, grayish (sometimes with rose or creamy tint), deeply umbilicate shell with five evenly rounded

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 sculpture shows strong, distant, spiral ridges, crossed by 10 to 12 fine, raised axial threads. The thin, finely crenulate outer

lip The lips are a horizontal pair of soft appendages attached to the jaws and are the most visible part of the mouth of many animals, including humans. Mammal lips are soft, movable and serve to facilitate the ingestion of food (e.g. sucklin ...

is sharp. The pearly rose

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 round. (Original description by

W.H. Dall William Healey Dall (August 21, 1845 – March 27, 1927) was an American naturalist, a prominent malacologist, and one of the earliest scientific explorers of interior Alaska. He described many mollusks of the Pacific Northwest of North America, ...

of the synonym ''Margarites (Pupillaria) rudis'') The shell is of moderate size. It is white with a pale olivaceous periostracum. The smooth nucleus consists of about one

and five subsequent whorls. The spiral

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

consists of two strong cords with wider interspaces and a thud on which the suture is laid and which forms the margin of the base. There is also a small thread between the suture and the posterior cord and on 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 ...

a similar thread in the interspaces. On the base there are six or seven smaller closer cords separated by obscurely channeled interspaces between the verge of a narrow umbilicus and the basal margin. The axial sculpture consists of (on the penultimate whorl about 20) retractive riblets extending from suture to periphery, with wider interspaces, slightly nodulous at the intersections with the spiral cords. There are also close obvious incremental regular lines over the whole surface. The simple, rounded aperture is quadrate. There is a glaze on the body. The inner

is slightly thickened. The operculum is multispiral.Dall (1919) Descriptions of new species of Mollusca from the North Pacific Ocean; Proceedings of the U.S. National Museum, vol. 56 (1920)
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Distribution

This marine species occurs in circum-arctic waters; from

Labrador Labrador () is a geographic and cultural region within the Canadian province of Newfoundland and Labrador. It is the primarily continental portion of the province and constitutes 71% of the province's area but is home to only 6% of its populatio ...

, Canada and

Greenland Greenland is an autonomous territory in the Danish Realm, Kingdom of Denmark. It is by far the largest geographically of three constituent parts of the kingdom; the other two are metropolitan Denmark and the Faroe Islands. Citizens of Greenlan ...

Cape Cod Cape Cod is a peninsula extending into the Atlantic Ocean from the southeastern corner of Massachusetts, in the northeastern United States. Its historic, maritime character and ample beaches attract heavy tourism during the summer months. The ...

, USA; from the

Bering Strait The Bering Strait ( , ; ) is a strait between the Pacific and Arctic oceans, separating the Chukchi Peninsula of the Russian Far East from the Seward Peninsula of Alaska. The present Russia–United States maritime boundary is at 168° 58' ...

to Southern

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

References

* Broderip, W. J. and G. B. Sowerby. 1829. ''Observations on new or interesting Mollusca contained, for the most part, in the museum of the Zoological Society.'' Zoological Journal 4: 359–379, pl. 9 * Couthouy, J. P. 1838. ''Descriptions of new species of Mollusca and shells, and remarks on several polypi found in Massachusetts Bay''. Boston Journal of Natural History 2: 53–111, pls. 1–3. * Möller, H. P. C. 1842. ''Index molluscorum Groenlandiae''. Naturhistorisk Tidsskrift 4: 76–97. * Kiener, L. C. 1848. ''Genre Turbo. (Turbo, Lin.). Spécies Général et Iconographie des Coquilles Vivantes'' 10: pls. 1–16, 16 is36 * Middendorff, A. T. von. 1849. ''Beiträge zu einer Malacozoologia Rossica. II. Aufzählung und Beschreibung der zur Meeresfauna Russlands gehörigen einschaler.'' Mémoires de l'Académie Impériale des Sciences de Saint-Pétersbourg, Sciences Naturelles (6)6: 329–516, pls. 1–11. * Mörch, O. A. L. 1857. ''Fortegnelse over Gro/nlands Blo/ddyr. Gro/nland Geographisk og Statistisk Beskrevet 2: 75–100'' Commission hos Universitetsboghandler: Kjo/benhavn. *Dautzenberg, P. and H. Fischer. 1912. ''Mollusques provenant des campagnes de l'Hirondelle et de la Princess-Alice dans les Mers du Nord''. Résultats des Campagnes Scientifiques du Prince de Monaco 37: 631 pp., 2 maps, 11 plates * Abbott, R.T. (1974). ''American Seashells''. 2nd ed. Van Nostrand Reinhold: New York, NY (USA). 663 pp * Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Mollusca, in: Costello, M.J. et al. (Ed.) (2001). ''European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification''. Collection Patrimoines Naturels, 50: pp. 180–213 * Kantor Yu.I. & Sysoev A.V. (2006) ''Marine and brackish water Gastropoda of Russia and adjacent countries: an illustrated catalogue''. Moscow: KMK Scientific Press. 372 pp. + 140 pls. page(s): 32 * Gulbin V.V. & Chaban E.M. (2012) ''Annotated list of shell-bearing gastropods of Commander Islands. Part I.'' The Bulletin of the Russian Far East Malacological Society 15–16: 5–30.

External links

* {{DEFAULTSORT:Margarites Costalis costalis Gastropods described in 1841