''Pareuthria atrata'' 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 ...

Cominellidae The Cominellidae are taxonomic family of large sea snails in the superfamily Buccinoidea.MolluscaBase eds. (2021). MolluscaBase. Cominellidae Gray, 1857. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.ph ...

.MolluscaBase eds. (2020). MolluscaBase. Pareuthria atrata (E. A. Smith, 1881). Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=889613 on 2020-11-17

Description

Shell medium sized, up to 22 mm in height, fusiform, of six convex whorls; protoconch of 2 ½ convex whorls, translucent, smooth, transition to teleoconch well defined; suture impressed, aperture oval, labrum expanded, sharp, with a small, curved subsutural slit; siphonal canal short; parietal callus very thin; axial ornamentation of about 10 to 12 varices, complete in all whorls but the last, where they vanish below middle whorl; some specimens, only with weak varices on the early whorls; spiral ornamentation of about 15 characteristic, regularly spaced striae per whorl, 30 on the last; periostracum absent (?); color typically pinkish, reddish or dark purple, inside creamy white; operculum brown, ovate, nucleus subterminal. Radula rachiglossate, very similar to ''P. fuscata'', but the cusps of the lateral teeth are more closely spaced in ''P. atrata'', particularly in the juvenile specimens. Penis large, long, subrectangular, flat, generally similar to that of '' Pareuthria fuscata''. Some minor differences are likely due to the reproductive stage and the reaction to critical point drying method.

Distribution

Off Buenos Aires province to Ushuaia, Tierra del Fuego, Malvinas and Staten Island, Argentina in the Atlantic; Southern Chile, Punta Arenas, to Calbuco (41°S) in the Pacific Ocean.

References

* Hombron, J.B. & Jacquinot, C.H. (1842-1854). Atlas d'histoire Naturelle zoologie par MM. Hombron et Jacquinot, chirurgiens de l'expédition. Voyage au Pole Sud et dans l'Océanie sur les corvettes l'Astrolabe et la Zélée éxecuté par ordre du roi pendant les années 1837–1838–1839–1840 sous le commandement de M. Dumont-d'Urville, capitaine de vaisseau, publié sous les auspices du département de la marine et sous la direction supérieure de M. Jacquinot, capitaine de vaisseau, commandant de la Zélée. Zoologie. Gide & Cie, Paris.

External links

Rochebrune A.-T. de & Mabille, J. (1889). Mollusques. in: Mission Scientifique du Cap Horn 1882-1883. Tome 6 (Zoologie 2, part 8). Paris, Gauthiers-Villars. H.1-H.129, pls. 1-8.

Pastorino G. (2016). Revision of the genera Pareuthria Strebel, 1905, Glypteuthria Strebel, 1905 and Meteuthria Thiele, 1912 (Gastropoda: Buccinulidae) with the description of three new genera and two new species from Southwestern Atlantic waters. Zootaxa. 4179(3): 301-344
{{DEFAULTSORT:Pareuthria Atrata Cominellidae Gastropods described in 1881