''Gymnobela abyssorum'' is a species of

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 ...

Raphitomidae Raphitomidae is a Family (biology), family of small to medium-sized sea snails, marine (ocean), marine gastropod mollusks in the superfamily Conoidea.Bouchet P. & Rocroi J.-P. (Ed.) (2005). "Classification and nomenclator of gastropod families" ...

Description

A biconical shell up to 23mm high with 6–7 shouldered whorls. Its diameter is 10 mm. Buff in colour with brownish marks. Description. – Shell of medium size, of a slightly ovoid elongated curve, a little more developed above than below. The obtuse

spire A spire is a tall, slender, pointed structure on top of a roof of a building or tower, especially at the summit of church steeples. A spire may have a square, circular, or polygonal plan, with a roughly conical or pyramidal shape. Spire ...

is of mediocre length. It is composed of 8 to 9

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 growing slowly in diameter and in height. They show a slightly concave-oblique profile on almost half of the height (more than half in the upper whorls, and less than half on the penultimate whorl). Then they become almost upright or slightly convex, with a keel sensitive to the change of direction of the whorls. The body whorl measures almost two-thirds of the total length. It is a slightly concave at the top. In lateral profile, on the opposite side to the 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 ...

, it becomes convex, then suddenly attenuated at the base. It ends in an open wide, short and almost straight

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 i ...

. The linear sutures are impressed. The small, mamillate

apex The apex is the highest point of something. The word may also refer to: Arts and media Fictional entities * Apex (comics) A-Bomb Abomination Absorbing Man Abraxas Abyss Abyss is the name of two characters appearing in Ameri ...

is followed by 3 to 4 embryonic, well rounded and very finely decussate whorls. The aperture measures half the total length. It is subrectangular-oblique, a little more narrowed at the base, inscribed in an almost vertical plane. The

peristome Peristome (from the Greek language, Greek ''peri'', meaning 'around' or 'about', and ''stoma'', 'mouth') is an anatomical feature that surrounds an opening to an organ or structure. Some plants, fungi, and shelled gastropods have peristomes. In mo ...

shows almost continuous edges. The thin and sharp outer edge is weakly projected forward, with a pleurotomoid notch at the top, perceptible though not very pronounced. Its lateral profile is as angular upwards, at the end of the keel, and then broadly convex-sloping towards the base. The columellar edge is a little arched at the top, upright towards the base where it ends pointedly. It shows in the upper part an accused callus. The solid shell is quite thick, subopaque, adorned with longitudinal ribs, decurrent cords and growth lines. It contains 18 to 19 longitudinal ribs on the penultimate whorl. These are large, rounded, spread out only on the base of whorls, mamillate at the keel, obsolete above, sometimes bifid below, slightly obliquely, very short on the body whorl, where they merge with growth lines. The decurrent striae are somewhat thin, regular, spaced, continuous, very attenuated at the top of the whorls, scarcely more marked at the base of the body whorl along the siphonal canal. The striations are strong, irregular, very wavy-flexuous. They form in the concave region of the whorls small corrugated folds, very close together. They blend in the body whorl, with the prolongation of the nodules of the keel. The color of the shell is a very light, non-glossy yellowish red, whiter on the inside.Locard A. (1897–1898). Expéditions scientifiques du Travailleur et du Talisman pendant les années 1880, 1881, 1882 et 1883. Mollusques testacés. Paris, Masson. vol. 1 [1897], p. 1–516 pl. 1-22; vol. 2 [1898], p. 1–515, pl. 1-18
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Distribution

This bathyal species (200 m to 1500 m) occurs in the Eastern

Atlantic Ocean The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the ...

; also off the

Azores The Azores ( , , ; , ), officially the Autonomous Region of the Azores (), is one of the two autonomous regions of Portugal (along with Madeira). It is an archipelago composed of nine volcanic islands in the Macaronesia region of the North Atl ...

in the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

References

* Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Mollusca. in: Costello, M.J. et al. (eds), European Register of Marine Species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Patrimoines Naturels. 50: 180–213
Bouchet & Warren, Revision of the North-East Atlantic bathyal and abyssal Turridae (Mollusca, Gastropoda); The Journal of Molluscan Studies, supplement 8, December 1980
* Sysoev A.V. (2014). Deep-sea fauna of European seas: An annotated species check-list of benthic invertebrates living deeper than 2000 m in the seas bordering Europe. Gastropoda. Invertebrate Zoology. Vol.11. No.1: 134–155 * Manousis, C. et al., 2018. The family Raphitomidae (Mollusca: Gastropoda: Conoidea) in the Greek Seas with the description of two new species.

External links

Serge GOFAS, Ángel A. LUQUE, Joan Daniel OLIVER, José TEMPLADO & Alberto SERRA (2021) - The Mollusca of Galicia Bank (NE Atlantic Ocean); European Journal of Taxonomy 785: 1–114

MNHN, Paris: ''Gymnobela abyssorum''

Tucker, J.K. 2004 ''Catalog of recent and fossil turrids (Mollusca: Gastropoda)''. Zootaxa 682:1–1295
{{DEFAULTSORT:Gymnobela Abyssorum abyssorum Gastropods described in 1897