Rhynchonellida

views updated May 08 2018

Rhynchonellida (rhynchonellids; class Articulata) Order of brachiopods (Brachiopoda), with rostrate shells, a functional pedicle, and a delthyrium partly restricted by a pair of deltidial plates. The shell is usually impunctate. They appeared first in the Middle Ordovician. The order contains about 250 genera, most of which are extinct.

Rhynchonellida

views updated May 21 2018

Rhynchonellida (phylum Brachiopoda, class Articulata) An order of brachiopods that have rostrate shells, a functional pedicle, and a delthyrium partly restricted by a pair of deltidial plates. The shell is usually impunctate. They appeared first in the Middle Ordovician. The order contains about 250 genera, most of which are extinct.

rhynchonellids

views updated May 08 2018

rhynchonellids See RHYNCHONELLIDA.