Terebratulida

Taxobox
name = Terebratulida
regnum = Animalia
phylum = Brachiopoda
classis = Articulata
ordo = Terebratulida
ordo_authority = Waagen, 1883
subdivision_ranks = Suborders
subdivision = See text.

Terebratulids are one of only two living orders of articulate brachiopods, the other being the Rhynchonellida. The name may be derived from the Latin "terebra", meaning "hole-borer". The perceived resemblance of terebratulid shells to ancient Roman oil lamps gave the brachiopods their common name "lamp shell".

Terebratulids typically have biconvex shells that are usually ovoid to circular in outline. They can be either smooth or have radial ribbing. The lophophore support is loop shaped in contrast to the spiralia of similar looking spiriferids. Terebratulids are also distinguished by a very short hinge line, and the shell is punctate in microstructure. There is a circular pedicle opening, or foramen, located in the beak.

Terebratulids may have evolved from Atrypids during the early or Middle Silurian. Early genera were almost circular to elongate-oval, with smooth or finely costate shells. During the Cretaceous and Tertiary periods, many shells became coarsely plicate.

Classification

* Suborder Terebratellidina
** Superfamily Kraussinoidea
** Superfamily Laqueoidea
** Superfamily Megathyridoidea
** Superfamily Platidioidea
** Superfamily Terebratelloidea
*** Family Dallinidae
*** Family Ecnomiosidae
*** Family Terebratellidae
*** Family Thaumatosiidae
** Superfamily Zeillerioidea
** Superfamily Bouchardioidea
** Superfamily Gwynioidea
** Superfamily Kingenoidea
** Superfamily Incertae sedis
*** Family Tythothyrididae
* Suborder Terebratulidina
** Superfamily Cancellothyroidea
** Superfamily Dyscoloidea
** Superfamily Terebratuloidea
*** Family Gryphidae
*** Family Tichosidae
*** Family Terebratulidae

Extinct Superfamilies
** Superfamily Dielasmatoidea †
** Superfamily Cryptonelloidea †
** Superfamily Loboidothyridoidea †
** Superfamily Stryingocephaloidea †

References