|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.
|P. Y. Parkhaev and Y. Demidenko 2010||"Hollow asymmetrical, curved or twisted, pyramidal sclerites, strongly compressed laterally. Sclerites narrow towards distal end. Transition between base and blade of sclerite gradual. Upper surface of sclerite always convex. Lower surface indistinct due to strong lateral compression of sclerite, it has variable profile, i.e., convex, flattened or concave. Lateral surfaces wide. Cross-section section in proximal part has narrow crescent, triangular, irregularly trapezoid or rhomboidal outlines. It differs from cross-section in distal part due to sclerite twisting. Distal end blind, rounded or pointed."|