Brachiopods: developing a bivalve shell
Some of these animals lived in secreted protective tubes, whereas others evolved two flat, protective shells which represented the first Brachiopods descendants which exist belong to the genus Lingula. Brachiopods had great variations in their design, including heavy lime shells, and large tentacles contained inside, whereas others developed a hole at the hinge end of one of the valves through which a stalk emerged and fastened the animal onto the ground.
LIVING BRACHIOPODS
Kingdom: Animalia
Phylum: Platyhelminthes
