with cup with or without proximale or distinct basals that may be hidden; cup may be elongated and columnlike. Column short; columnals, when present, cylindrical, without nodals and cirri, articulation symplectial to cryptosymplectial, immovable. Arms divided at primibrachial 1 or 2; no further division except in Neogymnocrinus
. Secundibrachials with muscular, rarely synostosial, articulations. Attachment by disk, where known, or cup attached directly to the substrate.
Hess H (2011) Cyrtocrinida. In: Hess H, Messing CG, Ausich WI (Eds.), Treatise on Invertebrate Paleontology, Part T, Echinodermata 2 Revised, Crinoidea, vol. 3. University of Kansas Press, Lawrence, Kansas, pp. 180–206.