Brachiopods are marine animals that live inside a shell made of two halves called valves.  At present brachiopods are only represented by a small number of species.  They can be found in the waters around New Zealand and Japan. 

In the past brachiopods were a far more successful group and are common fossils.  Brachiopods look very much like the bivalve shells you find on present day beaches all over the world, but the two groups are unrelated.

Brachiopods have a fleshy stalk that attaches them to the sea floor.  This stalk is called a pedicle and runs through a small hole in the base of one valve of the brachiopod’s shell.  The shell is drawn out into a beak shape around this hole.  This makes the two valves of the brachiopod’s shell different shapes.  Most bivalves have shells that are mirror images of each other and they don’t have a stalk to attach them to the sea floor.

Brachiopods feed by filtering small particles of food from the water around them.  A fleshy organ called the lophophore collects the particles.  The lophophore bears tiny hairs, which beat to produce a water current.  Food particles get caught on the sticky mucus covering the lophophore and are then carried to the mouth.  To separate the current of water entering the shell from that leaving it the front of the brachiopod shell is often folded down the middle.  This creates a distinctive pattern on the front of the brachiopod shell.    

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