Brachiopods (Phylum Brachiopoda)

© Craven & Pendle Geological Society

A Carboniferous Brachiopod

Dictyoclostus semireticulatus (Martin)

 A Carboniferous Brachiopod

Pugnax Hall & Clark, 1893

A Carboniferous Brachiopod

Schizophoria King, 1850

A Carboniferous Brachiopod

Rhynchonella Fischer, 1809

Class Articulata

These are sea floor dwellers (benthic).  Like all brachiopods, Productus, Pugnax, Rhynchonella and Schizophoria possess two separate calcareous valves - the brachial valve and the pedicle valve (a fleshy pedicle protrudes through a hole in the Pedicle valve, whilst the lophophore, or nutrient-gathering apparatus is attached to the brachial valve).

The means of connecting the valves together give rise to the terms Articulata (physical attachment) and Inarticulata (muscle-attachment).

The brachiopods differentiate themselves from bivalves by having their plane of symmetry about a medial plane.