Are benthic marine bivalves with most species having gone extinct at the end of the Permian. Brachiopods have a pedicle that emerges from the pedicle opening to help attach itself to the substrate. The pedicle is a long thin fleshy appendage in some brachiopods it is muscular to help it raise itself off the seafloor and although common it is not present in all brachiopods. Brachiopods are predominately filter feeders, using a crown of tentacles supported by cartilage called a lophophore. From the lophophore it is transported to the mouth, pharynx and then stomach. The lophophore takes up 2/3 of the inside of the shell with the rest of the body occupying the rest. Brachiopods first appeared during the early Cambrian quickly becoming one of the most abundantly found fossil in the world there was a great diversity of species during the Paleozoic but the P-T extinction reduced their numbers dramatically. Brachiopods are used often today as good index fossils.
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