Published online by Cambridge University Press: 14 July 2015
Extant comatulid (stalkless) crinoids consist of approximately 530 species, classified in 143 genera and 18 families (Clark, 1931, 1941, 1947, 1950; Clark and Clark, 1967; Messing and White, 2001). Recent comatulids account for almost 85% of all the extant crinoid species (comatulids plus stalked crinoids), and their taxonomy is currently being extensively revised (e.g., Hoggett and Rowe, 1986; Rowe et al., 1986; Messing and White, 2001). in stark contrast to such a high extant diversity, records of fossil comatulids are far less common. This is partly due to their low fossilization potential. From the Cretaceous, only 18 genera and nine families of comatulids have been documented (Rasmussen, 1978).