|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||Age range and collections|
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.
|S. M. Rowland and S. J. Carlson 1983||Cap-shaped shell, oval to semi-circular in outline; apex displaced center; weak concentric ornamentation valve apex, and rugae approximately bilaterally symmetrical. Internal features unknown.|