Brachiopod
Taxonomical history

Brachiopod

Section Title: Taxonomical history
Table Section Text: None

"Traditional" classification	Inarticulata	Articulata

"Calciata" approach	Lingulata	Calciata

Three-part approach	Linguliformea	Craniformea	Rhynchonelliformea

Orders	Lingulida	Discinida	Craniida	Terebratulida	Rhynchonellida

Hinge	No teeth	Teeth and sockets

Anus	On front of body, at end of U-shaped gut	None

Pedicle	Contains coelom with muscles running through	No pedicle	No coelom, muscles where joins body

Long, burrows	Short, attached to hard surfaces	None, cemented to surface	Short, attached to hard surfaces

Periostracum	Glycosaminoglycans and chitin	Chitin	Proteins

Primary (middle) mineralized layer of shell	Glycosaminoglycans and apatite (calcium phosphate)	Calcite (a form of calcium carbonate)

Inner mineralized layer of shell	Collagen and other proteins, chitinophosphate and apatite (calcium phosphate)	Calcite	Proteins and calcite

Chaetae around opening of shells	Yes

Coelom fully divided	Yes	No	Yes

Sentence(s)

In Brachiopod, the Lingulida and Discinida are grouped as Linguliformea, and the Rhynchonellida and Terebratulida as Rhynchonelliformea.

final_sentence: In Brachiopod, the Lingulida and Discinida are grouped as Linguliformea, and the Rhynchonellida and Terebratulida as Rhynchonelliformea.