Oval cockle
| Oval cockle | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Parvicardium pinnulatum | ||||||||||||
| ( Conrad , 1831) |
The oval cockle ( Parvicardium pinnulatum , syn .: Parvicardium ovale ) is a type of mussel from the family of cockles (Cardiidae) in the order Cardiida .
features
The equally flared, clearly inflated housing is up to 1.2 cm (1.5 cm) long and is slightly oblique-elliptical in outline. It is unequal-sided, especially juvenile housing, the vertebrae are clearly in front of the center, based on the length of the housing. In adult cases, the vertebrae are closer to the center. The anterior dorsal margin is short and merges into the anterior margin without a distinct kink. The posterior dorsal margin is also quite short; here the transition to the rear edge is more pronounced. The transition from the front edge to the ventral edge is more rounded than the transition from the rear edge to the ventral edge. The ventral margin is comparatively strongly curved. The ligament is distinct, but sunk. It sits on short nymphs. There is no lunula . The castle is poorly developed. In the right valve there are two anterior lateral teeth and one posterior lateral tooth and two cardinal teeth. The left valve has an anterior and posterior lateral tooth and two cardinal teeth. The surface line is not indented.
The shell is comparatively thin, but still firm. It is whitish with brownish tinted spots. The ornamentation consists of 24 to 26 (24 to 28) radial ribs. The ribs are low in profile and mostly flattened. The spaces between the ribs are narrow and significantly narrower than the ribs. The ribs on the front have small scales at wide intervals. The ribs on the middle part of the housing are mostly smooth, occasionally there are knotty spikes. The back ribs (about seven to eight) have small spines. The periostracum is thin but persistent. The inner edge of the housing is notched to match the ribs on the surface. The ribs are marked on the inside by furrows that can extend into the vertebral cavity.
Geographical distribution and habitat
The distribution area extends from Iceland over Northern Norway to the North Sea and the western Baltic Sea . In the south the distribution area extends to the Canary Islands and the coasts of the Mediterranean . In the western Atlantic, the distribution area extends into the coastal waters of the New England states in the USA .
The species lives shallowly buried in muddy-sandy to muddy-gravelly soils from shallow subtidal to about 100 meters water depth, in the North and Baltic Seas from about six to 30 meters water depth.
Taxonomy
The species was established in 1831 by Timothy Abbott Conrad as Cardium pinnulatum . In Europe, George Montagu first described the species in 1803 under the name Cardium elongatum . This name is preoccupied by Cardium elongatum Bruguière, 1789. George Brettingham Sowerby II therefore renamed the species Cardium ovale . The identity of the two taxa was recognized late, so that the species can often be found in European literature under Parvicardium ovale . MolluscaBase follows this synonymization .
supporting documents
literature
- Fritz Nordsieck : The European sea shells (Bivalvia). From the Arctic Ocean to Cape Verde, the Mediterranean Sea and the Black Sea. 256 pages, Gustav Fischer Verlag, Stuttgart 1969
- Guido Poppe, Yoshihiro Goto: European Seashells Volume 2 (Scaphopoda, Bivalvia, Cephalopoda) . 221 pp., Verlag Christa Hemmen, Wiesbaden 1993 (2000 unaltered reprint), ISBN 3925919104 (p. 99)
- Fritz Gosselck, Alexander Darr, Jürgen HJ Jungbluth, Michael Zettler: common names for mollusks of the sea and brackish water in Germany. Mollusca, 27 (1): 3-32, 2009 PDF
On-line
Individual evidence
- ↑ a b Rainer Willmann: Mussels and snails of the North and Baltic Seas. 310 p., Neumann-Neudamm, Melsungen 1989, ISBN 3-7888-0555-2 (p. 131 as Parvicardium ovale )
- ↑ Timothy Abbott Conrad: Description of fifteen new species of recent, and three of fossil shells, chiefly from the coast of the United States. Journal of the Academy of Natural Sciences of Philadelphia, 6 (2): 256-268, 1831 Online at www.biodiversitylibrary.org (p. 260)
- ↑ George Montagu: Testacea Britannica, or natural history of British shells, marine, land, and fresh-water, including the most minute: systematically arranged and embellished with figures. White, London 1803 Online at www.biodiversitylibrary.org (p. 82)
- ↑ George Brettingham Sowerby I, George Brettingham Sowerby II .: The conchological illustrations or, Colored figures of all the hitherto unfigured recent shells. London, privately published. 1832-1841 Online at Google Books (text)
- ↑ MolluscaBase: Parvicardium pinnulatum (Conrad, 1831)
