|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||Age range and collections|
Ophiuroidea - Phrynophiurida
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.
|H. Matsumoto 1915||Disk and arms covered by a skin. The radial shield and genital plate articulate by means of a simple face or a transverse ridge on either plate, without well-developed articular condyles and sockets. Peristomal plates large, entire, or sometimes double or triple. Oral frames entire, without well-developed lateral wings. Dorsal arm plates absent or very rudimentary; lateral arm plates ventral or subventral in position; dorsal side of arms largely unprotected.|