| Ruditapes decussatus (Linnaeus, 1758) |
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North Sea, Ireland to Sénégal, Azores to Mediterranean. Burrowed in intertidal to sublittoral soft sediments, chiefly in sheltered areas. Original taxon: Venus decussata.
5m deep, Ostriconi bay, Isola Rossa, Corsica. 41-43mm. |
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Shell ovate oblong, solid but not heavy, moderately thick; sculpture made up of very numerous thin radial striae crossed by well marked concentric ribs; pallial sinus deep. The synonymy reflects the high variability of the species: extensus, florida, fusca, obscura, truncata, variegata, vesta…
Palermo, Sicily. 41mm. |
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| Cap d’Agde, Occitania, S. France. 23mm. |
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| Variations in a population where all specimens share the same kind of pattern: entrance of Ayrolles lagoon, Gruissan, Occitania. 24-52mm. |
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| Hybrid specimens decussatus x philippinarum from Bay of Biscay. Intertidal on rocks, Pointe de Chauveaux, Sainte-Marie, Île de Ré, Charente-Maritime, W. France. 38-43mm. |
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Specimens from English Channel.
Plage du Sillon, Saint-Malo, N. Brittany, NW. France. 34mm. |
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| At low tide between stones on gravel bottom, Port-en-Bessin, S. Normandy, NW. France. 39-51mm. |
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A specimen from the northern limit of the range.
On shallow sand, Nordkoster, Koster Islands, Strömstad, Västra Götaland, SW. Sweden. 32mm. |
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| Venus decussata in G. P. Deshayes: “Hist. Nat. Moll.” t. I, Exploration scientifique de l’Algérie, Paris 1844-1867,
via BHL. |
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The two siphons of a specimen from Leucate, Occitania.
Original picture provided by S. Clanzig (FR).
– (CC BY-NC-SA) – |