Baltic macoma (juvenile´s shells)

Description:

Is a small saltwater clam, a marine bivalve mollusk in the family Tellinidae (the macomas and tellins). The shells are smooth, relatively flat, oval or somewhat trigonal in shape, and usually less than 20-30 mm long. The shell color is polymorphic, varying between individuals and between localities. Often most specimens are white, sometimes most are pink, and also yellow and orange shells may occur. Color is best visible in worn-out dead shells and inside the shell. Concentric growth rings indicating the age of the specimen are often clearly visible.

Habitat:

Macoma balthica lives in the northern parts of both the Atlantic and Pacific oceans, and also extends to the Subarctic both in North America and in Europe. Macoma is an infaunal bivalve, living buried in the mud or silt, and extending its two narrow siphons to the bottom surface. Throuhg the siphons, it feeds on organic matter on the sediment surface or in the water. Macoma is a euryhaline species, capable of living in a wide range of water salinity, down to 3-4 permille, i.e. 10 % of ocean salinity. It usually lives in the intertidal or shallow subtidal. In the brackish Baltic Sea it lives submerged down to depths over 100 m.