Little pepper clam
| Little pepper clam | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Little pepper clam ( Abra alba ) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Abra alba | ||||||||||||
| ( W. Wood , 1802) |
The Abra alba ( Abra alba ), also white pepper mussel is a bivalve mollusc of the family of pepper shells (Semelidae). It is also found in the North and Baltic Seas.
features
The almost equally-flattened, flattened housing of the white pepper clam is rounded and triangular with a length of up to 25 millimeters. It's twisted very slightly to the right. The outline is somewhat variable. In the northern part of the distribution area, the housings are also somewhat larger than in the Mediterranean. The case is almost equilateral, the vertebrae are only slightly shifted behind the center line (based on the length of the case). The posterior dorsal margin is almost straight and slopes down to the tightly rounded posterior end. The anterior dorsal margin is very flat, slightly longer than the posterior dorsal margin, and slopes more flatly towards the broader, rounded front end. The ligament is external and internal. The external ligament is a small, dark brown band behind the vertebrae. The internal ligament sits in a small triangular, rearward-facing chondrophore . The lock has a small cardinal tooth and a weak anterior and posterior lateral tooth in the left valve in front of the ligament pit. In the right valve there are two cardinal teeth and two very weak lateral teeth, one anterior and one posterior. The surface line is deeply indented. The soft body is whitish with a bluish tinge and pure white spots. The siphons are about as long as the housing.
The shell is very thin and fragile. The surface shows very fine concentric growth strips. The color of the shell is dirty white, the periostracum is light brown. The inner edge of the case is smooth.
Geographical distribution, habitat and way of life
The small pepper clam occurs on the coasts of the North and Baltic Seas, in the eastern Atlantic from Norway to northwest Africa, and in the Mediterranean and Black Sea from the low water line to depths of around 65 meters. It lives buried in muddy, sandy-muddy and fine sandy soils.
Food is mainly consumed through the long siphons, which quasi pipette off the sediment surface for organic matter. The siphons are moved in a circle around the animal. The food can also be obtained by filtering. The little pepper clam is separate sexes. The sex products are released into the open water. The animals are only one to three years old.
Taxonomy
The taxon was proposed in 1802 by William Wood in the combination Mactra alba . The species is now generally recognized as belonging to the genus Abra Lamarck, 1818.
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 and Yoshihiro Goto: European Seashells Volume 2 (Scaphopoda, Bivalvia, Cephalopoda) . 221 pp., Verlag Christa Hemmen, Wiesbaden 1993 (2000 unc. Reprint), ISBN 3925919104 (p. 116)
- Rainer Willmann: Mussels and snails of the North and Baltic Seas. 310 p., Neumann-Neudamm, Melsungen 1989, ISBN 3-7888-0555-2 (p. 155)
On-line
Individual evidence
- ^ SF Rainer: Population dynamics and production of the bivalve Abra alba and implications for fisheries production. Marine Biology, 85: 253-262, 1985.
- ^ William Wood: Observations on the Hinges of British Bivalve Shells. Transactions of the Linnean Society of London, 6: 154-176, London 1802 Online at www.biodiversitylibrary.org (p. 165)
- ↑ MolluscaBase: Abra alba (W. Wood, 1802)
