|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Rhynchonellata - Atrypida - Lissatrypidae
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.
|P. Copper 1995||Relatively small, primarily smooth or weakly weakly plicate; anterior fold sharply or weakly defined by two divergent "ribs" lining sulcus on ventral valve; internally prominent dental cavities; raised hinge plate fused centrally by inner socket ridges; low-spired, dorsally directed spiralia; jugal processes terminating in thick jugal plates.|