Triangular clam
| Triangular clam | ||||||||||||
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![Triangular clam (Gouldia minima) (from GB Sowerby II 1859: Plate 5, Fig. 2 [1])](https://de.wikipedia.org/wiki/Datei:Illustrated_Index_of_British_Shells_Plate_05_Fig_2_Gouldia_minima.png)
Triangular clam ( Gouldia minima ) (from GB Sowerby II 1859: plate 5, fig. 2) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Gouldia minima | ||||||||||||
| ( Montagu , 1803) |
The triangular clam ( Gouldia minima ) is a clam living in the sea - a species of the clams family (Veneridae).
features
The evenly folded, moderately expanded case is roughly triangular or rounded in outline. It is almost equilateral, with the vertebrae just in front of the midline. It becomes up to 16 mm long. Nordsieck gives the following width / height / thickness values: 10/9/5 mm, the anterior dorsal margin drops off steeply and is straight. The posterior dorsal margin is a little flatter and is convex. The ventral margin is well arched. The lunula is clearly set off, oblong-lanceolate with radial pits. The area , on the other hand, is only indistinct. The ligament is sunk and extends over half of the posterior dorsal margin. The lock has three diverging main teeth in each flap. Two front posterior teeth are added in the right valve. There is only one anterior posterior tooth in the left flap. The two sphincters are roughly the same size and clearly outlined on the shell. The mantle bay is very small, a small, shallow indentation, and sits just below the posterior sphincter muscle. The inner edge of the case is smooth.
The shell is thick and tight. The ornamentation consists of ribs and pits parallel to the edge. Ribs and pits are almost smooth, apart from fine strips of growth. The periostracum is thin and silky-shiny. The color varies from whitish, brownish, red to purple with darker stripes, lines, rays and spots on a lighter background. The inside of the bowl is shiny white.
The soft body is gray and translucent. The coat is provided with brown spots and has short, cylindrical papillae. The siphons are of unequal length, overall quite short. The foot is comparatively large and tongue-shaped and functions as a grave foot.
Geographical distribution, habitat and way of life
The distribution area of the species in the East Atlantic extends from Norway to West Africa (Ivory Coast) as well as into the Mediterranean and into the Black Sea . It is also found in the waters around the Azores , Madeira, and the Canary Islands .
The animals live buried in sandy soils, muddy soils, but also sandy to gravelly soils from 8 meters deep to the continental margin. The deepest evidence comes from 1287 meters water depth (Nordsieck). The animals feed on microorganisms by filtering.
Similar species
The triangular clam ( Gouldia minima ) differs from the rough clam ( Venus verrucosa ) by the very small mantle bay and the two posterior teeth in the right valve. In this species the ribs parallel to the edge are warty.
Taxonomy
Georg Montagu introduced the taxon into scientific literature in 1803 in the original combination Venus minima . Today it is placed very generally in the genus Gouldia CB Adams, 1847. It used to be placed in the genus Circe and Gafrarium . MolluscaBase listed a number of synonyms: Circe minima (Montagu, 1803) Circe minima var. Minor Marion, 1883, Circe striata Locard, 1892, Circe undulata Locard, 1892, Cytherea apicalis Philippine 1836 Cytherea sismondae Calcara, 1845 Gouldia minima var. citrina Bucquoy, Dautzenberg & Dollfus, 1893, Gouldia minima var. mirabilis Bucquoy, Dautzenberg & Dollfus, 1893, Gouldia minima var. penicillata Bucquoy, Dautzenberg & Dollfus, 1893, Gouldia minima var. rubicunda Bucquoy, Dautzenberg & Dollfus, 1893, Gouldia planata distantelamellata Nordsieck, 1969, Venus cyrilli Scacchi, 1832, Venus inquinata Lamarck, 1818, Venus pumila Lamarck, 1818 and Venus triangularis Montagu, 1803.
supporting documents
literature
- Rudolf Kilias: Lexicon marine mussels and snails. 2nd edition, 340 p., Verlag Eugen Ulmer, Stuttgart 1997 ISBN 3-8001-7332-8 (p. 133)
- 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. 107/08)
- Guido Poppe & Yoshihiro Goto: European Seashells Volume 2 (Scaphopoda, Bivalvia, Cephalopoda) . 221 p., Verlag Christa Hemmen, Wiesbaden 1993 (2000, un. Reprint). ISBN 3925919104 (p. 122)
On-line
- Marine Bivalve Shells of the British Isles: Gouldia minima (Montagu, 1803) (website of the National Museum Wales, Department of Natural Sciences, Cardiff)
- Marine Species Identification Portal: Gouldia minima (Montagu, 1803)
- Gouldia minima (Montagu, 1803) Conchological Society of Great Britain and Ireland (accessed May 17, 2017).
Individual evidence
- ↑ George Brettingham Sowerby II : Illustrated index of British shells. containing figures of all the recent species, with names and other information. XV S., XXIV plate London, Simpkin, Marshall & Co., 1859 Online at www.biodiversitylibrary.org (plate 5)
- ↑ 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
- ↑ 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. SI-XXXVII (= 1-37), pp. 1–606, Taf. 1–16, White, London, 1803 Online at www.biodiversitylibrary.org (p. 121)
- ↑ a b MolluscaBase: Gouldia minima (Montagu, 1803)