Mya truncata
The truncate Klaffmuschel (Latin Mya truncata ) is a species of bivalve mollusc of the order Myoida. Their main area of distribution are the Arctic waters.
Features
The case of the truncated Klaffmuschel is oblong - oval with an almost straight cut rear end. It is up to almost 8 inches long and gapes at the back end. The swirl is located in the rear half of the housing. The surface is covered with concentric growth lines. The organic periostracum is yellowish. The ligament is on the inside and outside. For attachment of the ligament inside a spoon -shaped extension is developed in the left flap below the vortex, which has its counterpart in a pit on the right flap. Otherwise, no teeth on the lock edge are developed. The right door is slightly larger than the left door. The siphons can be stretched to twice its body length; but they can be fully retracted into the housing also. The jacket bay is deep and wide.
Distribution, occurrence and life
The range of the species is mainly restricted to the Arctic waters of the North Atlantic and North Pacific. In the south, it comes up in the Bay of Biscay and the North Sea ( including the western Baltic Sea). In the North and Baltic Sea it is reached a relatively rare species, the maximum colonization densities of 1 individual per m2. In Arctic waters, however, colonization densities come from up to 100 individuals per m2 in front. In the Wadden Sea in the southern North Sea, the sand gaper truncate occurs together with the sand gaper in the tidal area. It goes, in contrast to the sand gaper up to 70 m depth. In the Baltic, she lives in 10 to 30 m depth. The animals live buried in sandy- silty sediment (up to about 15 cm). She is an outspoken cold water form that tolerates even the slightly higher temperatures of Biscay, North Sea and Baltic Sea. However, they spawn in these areas from the winter, when water temperatures such as those prevail in Greenland in the summer. In some years, the reproductive cycle falls off completely. This could be due to the increased in recent decades, water temperatures of the North Sea during the winter months. You should to 8 years old The shell is the main food of the walrus ( Odobenus rosmarus ).