Antedonidae with centrodorsal conical, low hemispherical or almost discoidal, with large cavity. Cirrus sockets rather small, 10-100, in alternating, irregular rows with tendency to form up to 30 columns; socket size may increase toward centrodorsal base. Cirrus-free aboral apex generally small, pointed to rounded, and smooth, rarely rugose. Length of cirri moderate; apical cirri rather short. Cirrals laterally compressed and generally long; length 1-6 times width. Distal cirrals commonly aborally carinate, sometimes with aboral spine. Basal rosette without rod-shaped basals. Exposed surface of radials short to large. Radial articular facet high and steep. Interarticular ligament fossae triangular or low; narrow ridge separating interarticular fossae from adoral muscle fossae may be almost horizontal, straight or curved. Adoral muscle fossae large and high, rounded subtriangular with rounded adoral edge, separated by low narrow median ridge and small notch. Radial cavity narrow. 10 arms. Synarthry between primibrachials 1 and 2 commonly embayed. Primibrachial 1 commonly with parallel or converging sides and laterally overhung by primibrachial 2. First pinnule stiff and slender with elongate pinnulars. Second pinnule commonly the first genital pinnule.
Hess H, Messing CG (2011) Comatulida. In: Hess H, Messing CG, Ausich WI. Treatise on Invertebrate Paleontology, Part T, Echinodermata 2 Revised, Crinoidea, vol. 3. University of Kansas Press, Lawrence, Kansas, pp. 70–146.