|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.
|L. E. Popov et al. 2009||Ventribiconvex, about 75–80 per cent as long as wide; hinge line slightly shorter than maximum shell width which is close to mid-length, cardinal extremities obtuse; ventral valve evenly convex in transverse and lateral profiles; dorsal valve lacking distinct median sulcus; radial ornament of 18–27 ribs and superimposed fine capillae at about seven to nine per 1 mm.|