👉 Haematoloechus is a genus of bivalves that primarily inhabit freshwater environments, including lakes and rivers. They are characterized by their complex, elongated shell with a smooth, translucent surface and numerous minute arms on both sides of the body. The shell is made up of two layers: the outermost layer is called the mantle, which contains the internal organs, while the inner shell is known as the caudal or mantle.