|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Eocrinoidea - Palaeocystitidae
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.
|J. Sprinkle 1982||Palaeocystitids with a large clubshaped or ovoid theca; 8 to 18 columns of plates, 3 unequal basals (2 larger, 1 smaller), plates 4- to 8-sided, slightly arched or domed, highly ornamented; mouth central on summit, surrounded by 5 short recumbent ambulacra forming thecal wall, 2 to 10 biserial brachioles attached to each, brachioles long, either erect or recumbent down theca; anus on side of theca in BC interray, from 2 to 5 thecaL plates below hydropore, surrounded by 5 to 6 thecal plates, protected by 5 periproctal cover plates; long slitlike (rarely branched) hydropore and adjacent small gonopore in CD interray below mouth, both may cross sutures; externally covered sutural pores present on edges of most thecal plates with simple tangential canals extending toward plate centers, 2 to 13 pores per suture; stem apparently long, circular, with medium to large diame:.er, lumen elliptical to rounded-triangular, stem apparently terminating in type 4 holdfast.|