|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||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.
|D. B. Blake and H. Hagdorn 2003||Asteroids with ambulacrals and adambulacrals alternating (offset), ambulacrals abutting two successive adambulacrals. More or less prominent winglike facets on ambulacrals support connective tissues extending to grooves on adambulacrals. Adradially, longitudinal
ambulacral-ambulacrat articular surfaces clearly differentiated. Dorsal podial pores well developed, therefore ambulacrals more or less hourglassshaped.
Adambulacrals broadly of inverted J-shape, linked ventrally by large interadambulacral muscle depressions; hook of inverted "J" abuts, overlaps successively; direction of overlap either distal or proximal. In ventral arm view of undistorted specimen, subsequent adambulacrals separated by muscle gap.