Date mussel
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Pholas dactylus (Linnaeus, 1758) |
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| Scientific name | ||||||||||||
| Pholas dactylus | ||||||||||||
| Linnaeus , 1758 |
The Dattelmuschel ( Pholas dactylus ) or Large piddock is a drilling in hard substrate shell -Art from the family of lithophagous molluscs (Pholadidae) in order of Myida .
features
The puffed up, almost equally hinged housing is elongated-elliptical in outline. It becomes up to 150 millimeters long. It is very unequal, the vertebrae sit well in front of the midline. The front end tapers like a finger or beak, the rear end is evenly rounded. The housing gapes permanently at both ends. The ventral margin from the rear end to about level with the vertebra is almost straight. The upper edge is turned over in two layers to the outside and the top. While the envelope of the lower layer lies directly on the flap, the second layer protrudes freely. The space is divided by 9 to 14 vertical septa. Additional shell plates form between the two valves with protoplax, mesoplax and metaplax.
The ligament sits on the inside on a protruding chondrophore. The inner edge is smooth. The wide jacket bay extends to the center line of the housing. The anterior sphincter muscle attaches to the shell envelope. The foot muscles sit on a small process in each valve.
The whitish skin is brittle and moderately firm. The ornamentation consists of concentric ribs and an additional 40 radial ribs at the front. The intersection of concentric and radial ribs are drawn out to form strong thorns. The edge around the foot opening is therefore strongly serrated. The periostracum is yellowish to light brown.
Geographical distribution, habitat and way of life
The distribution area extends from Norway , over the British Isles , the North Sea , the east Atlantic coasts of Western Europe to Morocco as well as into the Mediterranean and the Black Sea . It is also found in the Canary Islands .
The date mussel prefers to drill in solid sediments and hard rock, but also in wood and lives deep in these boreholes. The long siphons are brought up to the opening of the borehole. When disturbed, the jacket and siphons secrete a fluorescent mucus. It occurs from the tidal range to about ten meters water depth.
Taxonomy
The taxon was introduced into scientific literature in 1758 by Carl von Linné in its current form Pholas dactylus . It is the type species of the genus Pholas Linnaeus, 1758.
supporting documents
literature
- S. Peter Dance, Rudo von Cosel (arrangement of the German edition): The great book of sea shells. 304 p., Verlag Eugen Ulmer, Stuttgart, 1977 ISBN 3-8001-7000-0 (p. 272/73)
- Rudolf Kilias: Lexicon marine mussels and snails. 2nd edition, 340 p., Verlag Eugen Ulmer, Stuttgart 1997 ISBN 3-8001-7332-8 (p. 249/51)
- 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. 153)
- Guido Poppe. Yoshihiro Goto: European Seashells Volume 2 (Scaphopoda, Bivalvia, Cephalopoda) . 221 p., Verlag Christa Hemmen, Wiesbaden 1993 (2000 unc. Reprint), ISBN 3925919104 (p. 132)
- Rainer Willmann: Mussels of the North and Baltic Seas. 310 p., Neumann-Neudamm, Melsungen 1989 ISBN 3-7888-0555-2 (p. 190/91)
On-line
- Marine Bivalve Shells of the British Isles: Pholas dactylus Linnaeus, 1758 (site of the National Museum Wales, Department of Natural Sciences, Cardiff)
Individual evidence
- ↑ Fritz Gosselck, Alexander Darr, Jürgen HJ Jungbluth, Michael Zettler: Trivial names for mollusks of the sea and brackish water in Germany. Mollusca, 27 (1): 3-32, 2009 PDF
- ^ Carl von Linné: Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. Pp. 1-824, Holmia / Stockholm, Salvius, 1758. Online at www.biodiversitylibrary.org (p. 669).
- ↑ MolluscaBase: Pholas dactylus Linnaeus, 1758
