''Pareuthria atrata'' 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 ...

mollusk 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 e ...

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 ...

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 ''Pareuthria fuscata'' is a species of sea snail, a marine gastropod mollusk in the family Cominellidae. Description The size of the shell varies between 25 mm and 45 mm. The ovate, conical shell is smooth and reddish brown. The spi ...

''. 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