Coracuta obliquata

Coracuta obliquata
Coracuta obliquata
Systematics
Superordinate : Imparidentia Order : Superfamily : Galeommatoidea Family : Lentil mussels (Montacutidae) Genre : Coracuta Type : Coracuta obliquata
Scientific name of the  genus
Coracuta
Holmes , Gallichan & Wood , 2006
Scientific name of the  species
Coracuta obliquata
( Chaster , 1897)

Coracuta obliquata is a type of mussel from the lentil mussel family(Montacutidae). It is the type and only species of the genus Coracuta Holmes, Gallichan & Wood, 2006.

features

The even-folded, very small, moderately distended cases are oblique-egg-shaped to teardrop-shaped and are up to three millimeters long. They are unequal, the vertebrae shifted towards the rear end; they sit about two-thirds of the length of the case from the front end. The posterior dorsal margin is short, almost straight to very slightly convex, and slopes steeply towards the posterior end. The transition to the slightly curved rear end is slightly angled, as is the transition from the rear end to the ventral edge. The anterior dorsal edge is also straight at first and merges with the wide, curved anterior edge at a flat angle. The front edge then merges into the broadly rounded ventral edge without any noticeable interruption of the curve. The Prodissoconch is smooth; the Prodissoconch I measures 79 µm, the Prodissoconch II 344 µm.

The lunula , defined by a small bulge, is narrow and elongated. The externally located ligament is comparatively large and sits on a flat ligament support, below and slightly behind the vertebrae. In the right valve there is an anterior and a posterior lateral tooth; the back one is about three times as long as the front one. The edge of the lunula and the lateral teeth enclose longitudinal pits between them. The posterior lateral tooth forms a V-shaped pit at the rear end.

In the left valve there is a small cusp below and slightly in front of the vertebra, but no lateral teeth. Instead, the dorsal edges of the housing are elongated into flanges; they fit into the pits in the right flap. The surface line is complete.

The cream-colored to light brown, shiny skin is thin and fragile. The ornamentation consists of fine, parallel to the edge, sharp ribs that undulate irregularly and occasionally split or merge. The inner edge of the case is smooth. The periostracum is brown.

Geographical distribution and habitat

The distribution area extends from the British Isles , including the southern North Sea to the Mediterranean . It lives in sandy silt or silty sand in 22 to 62 meters water depth.

Taxonomy

George W. Chaster established the taxon in 1897 as Neolepton obliquatum . It was later placed in the genus Mysella . For this species Anna Holmes, Jennifer Gallichan and Harriet Wood suggested the genus Coracuta . Species and genus are accepted by MolluscaBase as valid taxa.

supporting documents

literature

• Anna Holmes, Jennifer Gallichan, Harriet Wood: Coracuta obliquata n. Gen. (Chaster, 1897) (Bivalvia: Montacutidae) - First British record for 100 years. Journal of Conchology 39 (2): 151-158, 2006.

On-line

• Marine Bivalve Shells of the British Isles: Coracuta obliquatum (Chaster, 1897) (site of the National Museum Wales, Department of Natural Sciences, Cardiff)

Individual evidence

1. ↑ Carmen Salas: Marine bivalves from off the Southern Iberian Peninsula collected by the Balgim and Fauna 1 expeditions. Haliotis, 25: 33-100, 1996 PDF (ResearchGate) (p. 62)
2. ↑ George W. Chaster: Notes on the marine Mollusca of Rathlin Island. The Irish Naturalist, 6: 184-187, 1897 Online at www.biodiversitylibrary.org (p. 186).
3. ↑ MolluscaBase: Coracuta obliquata (Chaster, 1897)

Web links

Commons : Coracuta obliquata  - collection of images, videos and audio files