NEW PHYLOGENY-BASED AND LINNAEAN CLASSIFICATIONS OF THE CRINOIDEA (ECHINODERMATA)
A series of stem- and node-based definitions are proposed to recognize these clades. In addition, recent phylogenetic analyses support the resurrection of two names previously abandoned in the crinoid taxonomic literature: the Pentacrinoidea Jaekel, 1918 and Inadunata Wachsmuth and Springer, 1885. A rank-based classification is also proposed that reflects the clades recognized in recent computational analyses. The traditional taxonomic system is preserved where possible. However, numerous changes were necessary to achieve monophyly, especially above the order level. These phylogeny-based revisions provide a useful template for crinoid paleontologists, biologists, and non-experts alike to better explore evolutionary patterns and processes with fossil and living crinoids.