|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Rhynchonellata - Orthida - Orthidae
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|C. M. O. Rasmussen et al. 2012||Shell small, ventri-biconvex with transversely lobate to triangular outline. Cardinal angles alate. Ventral interarea moderately high, dorsal interarea low. Delthyrium long, covered by pseudodeltidium. Teeth large. Notothyrium open and wide. Ornamentation consists of simple, widely spaced costae. Dental sockets deep; brachiophores widely divergent. Cardinal process weak, blade-like.|