Blue mussel

Blue mussels are boreo-temperate invertebrates that live in intertidal areas attached to rocks and other hard substrates by strong (and somewhat elastic) thread-like structures called byssal threads; these are secreted by byssal glands located in the foot of the mussel. Polyphenolic proteins are proteins produced by some algae and marine invertebrates like the blue mussel to serve as bioadhesive.
The shape of the shell is triangular and elongate with rounded edges. The shell is smooth with a sculpturing of fine concentric growth lines but no radiating ribs. The shells of this species are purple, blue or sometimes brown in color, occasionally with radial stripes. Blue Mussels are semi-sessile, have the ability to detach and reattach to a surface allowing the mollusk to reposition itself relative to the water position.