|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Rhynchonellata - Pentamerida - Parastrophinidae
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.
|J. Jin and L. E. Popov 2008||Shell small, transversely elliptical to subpentagonal, dorsibiconvex, smooth posteriorly, weakly costate anteromedially; dorsal valve notably larger, deeper, with higher and more prominent umbo than ventral valve. Anterior commissure uniplicate, variably asymmetrical or sigmoidal. Ventral sulcus and dorsal fold developed anteriorly, broad and variously asymmetrical. Ventral median septum short, very low; inner hinge plates high, discrete, subparallel to each other; alate plates well developed.|