| 1 | A | B | C | D | E | F |
| --- | --- | --- | --- | --- | --- | --- |
| 2 | Brachiopod - Taxonomical history |  |  |  |  |  |
| 3 | "Traditional" classification | Inarticulata | Inarticulata | Inarticulata | Articulata | Articulata |
| 4 | "Calciata" approach | Lingulata | Lingulata | Calciata | Calciata | Calciata |
| 5 | Three-part approach | Linguliformea | Linguliformea | Craniformea | Rhynchonelliformea | Rhynchonelliformea |
| 6 | Orders | Lingulida | Discinida | Craniida | Terebratulida | Rhynchonellida |
| 7 | Hinge | No teeth | No teeth | No teeth | Teeth and sockets | Teeth and sockets |
| 8 | Anus | On front of body, at end of U-shaped gut | On front of body, at end of U-shaped gut | On front of body, at end of U-shaped gut | None | None |
| 9 | Pedicle | Contains coelom with muscles running through | Contains coelom with muscles running through | No pedicle | No coelom, muscles where joins body | No coelom, muscles where joins body |
| 10 | Pedicle | Long, burrows | Short, attached to hard surfaces | None, cemented to surface | Short, attached to hard surfaces | Short, attached to hard surfaces |
| 11 | Periostracum | Glycosaminoglycans and chitin | Glycosaminoglycans and chitin | Chitin | Proteins | Proteins |
| 12 | Primary (middle) mineralized layer of shell | Glycosaminoglycans and apatite (calcium phosphate) | Glycosaminoglycans and apatite (calcium phosphate) | Calcite (a form of calcium carbonate) | Calcite (a form of calcium carbonate) | Calcite (a form of calcium carbonate) |
| 13 | Inner mineralized layer of shell | Collagen and other proteins, chitinophosphate and apatite (calcium phosphate) | Collagen and other proteins, chitinophosphate and apatite (calcium phosphate) | Calcite | Proteins and calcite | Proteins and calcite |
| 14 | Chaetae around opening of shells | Yes | Yes | - | - | - |
| 15 | Coelom fully divided | Yes | Yes | No | Yes | Yes |

Question: How are the Lingulida and Discinida grouped? 
Answer: In Brachiopod, the Lingulida and Discinida are grouped as Linguliformea, and the Rhynchonellida and Terebratulida as Rhynchonelliformea.