Lime flat mussel
| Lime flat mussel | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Lime flat mussel ( Macoma calcarea ) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Macoma calcarea | ||||||||||||
| ( Gmelin , 1791) |
The calcareous flat mussel ( Macoma calcarea ) is a type of mussel from the Tell mussel family (Tellinidae). It is also found in the North and Baltic Seas .
features
The unevenly hinged, non-inflated case reaches a length of 50 millimeters (and a height of 34 mm and a thickness of 14 mm). The right door is slightly larger than the left door. It's also unequal, the small, protruding vertebrae sitting behind the center (at about 40% from the posterior end). The housing is broadly ovoid in outline, with a wedge-shaped rear end. The length to height ratio is about 1.4. The rear part of the case is bent slightly to the right. The posterior dorsal margin is almost straight and slopes steeply to the tightly rounded posterior end. The anterior dorsal margin is arched flat convex and slopes down to the wide rounded anterior end. The ventral margin is well rounded. The case gapes at both the front and rear ends. There is a small dent in the back of the ventral margin.
The brown ligament extends behind the vertebrae for half the length of the posterior dorsal margin. There are two cardinal teeth in each valve, but no lateral teeth. In the left valve, the anterior cardinal tooth is furrowed and bilobed, while the posterior cardinal is small. In the right valve, the posterior cardinal tooth is furrowed and bilobed, and the anterior cardinal tooth is small. The coat is deeply indented, but the indentation has a slightly different shape in the right and left flaps. In the left valve, the bay is more tongue-shaped and very long, reaching almost to the anterior sphincter muscle. In the right flap, the bay is much shorter. There are two sphincters, the front one of which is slightly longer.
The cream-colored skin is thick-walled but a little brittle. The surface shows fine ribs and depressions parallel to the edge at irregular intervals. The edge of the housing is smooth without notches or the like. The brown periostracum flakes off easily and is mostly only preserved at the edge of the housing.
Similar species
The lime flat mussel is more elongated, has a larger length to width ratio and is less flattened than the Baltic flat mussel ( Macoma balthica ). The latter is also significantly smaller, only about half the size.
Geographical distribution and habitat
The calcareous flat mussel occurs circumpolarly in the northern North Atlantic, northern Pacific and the Arctic Ocean. On the eastern side of the Atlantic, the species penetrates into the North Sea and Baltic Sea. In the western Atlantic it occurs up to the height of New York. In the western North Pacific, the southern limit of distribution is approximately at the level of Oregon, in the eastern North Atlantic in northern Japan.
Adult specimens are often buried up to 20 cm deep in fine sand or silt soils. They occur from the tidal range to a depth of 1,600 meters. The limestone flat mussel is a cold water species, in the North and Baltic Seas it occurs only in areas where the water temperature does not exceed 11 ° C.
The species is one of the most important food organisms for the threatened plush head duck Somateria fischeri in the Bering Sea.
Taxonomy
The species was founded by Johann Friedrich Gmelin as Tellina calcarea . It is de facto the type species of the genus Macoma Leach, 1819. The formal type species Macoma tenera Leach, 1819, is a more recent synonym of Macoma calcarea .
supporting documents
literature
- 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 (p. 26)
- Fritz Nordsieck: The European sea shells (Bivalvia). From the Arctic Ocean to Cape Verde, the Mediterranean Sea and the Black Sea. 256 p., Gustav Fischer Verlag, Stuttgart 1969 (p. 129)
- Guido Poppe. Yoshihiro Goto: European Seashells Volume 2 (Scaphopoda, Bivalvia, Cephalopoda) . 221 pp., Verlag Christa Hemmen, Wiesbaden 1993 (2000 unc. Reprint), ISBN 3925919104 (p. 109)
- Rainer Willmann: Mussels of the North and Baltic Seas. 310 p., Neumann-Neudamm, Melsungen 1989 ISBN 3-7888-0555-2 (p. 168)
On-line
- Marine Bivalve Shells of the British Isles: Macoma calcarea (Gmelin, 1791) (site of the National Museum Wales, Department of Natural Sciences, Cardiff)
- Marine Species Identification Portal: Macoma calcarea (Gmelin, 1791)
Individual evidence
- ↑ Samantha E. Richman, James R. Lovvorn (2003): Effects of clam species dominance on nutrient and energy acquisition by spectacled eiders in the Bering Sea. Marine Ecology Progress Series 261: 283-297.
- ^ Johann Friedrich Gmelin: Caroli a Linné, systema naturae. Tom. I. Pars VI. Pp. 3021–3910, Lipsia / Leipzig, Beer, 1791 Online at www.biodiversitylibrary.org (p. 3236)
- ↑ MolluscaBase: Macoma calcarea (Gmelin, 1791)
