Paradelocrinidae

Posterior (top), oral and aboral (bottom) views of cup of Atokacrinus obscurus, from Moore et al. (1978).

Belongs within: Erisocrinacea.

The Paradelocrinidae are a group of relatively small crinoids known from the Upper Carboniferous and the Permian (Moore et al. 1978).

Characters (from Moore et al. 1979): Base of cup broadly to narrowly concave, moderate in depth or shallow; infrabasals five, downflared steeply or gendy, mostly covered by stem; proximal part or all of basals included in concavity; radials wide, with planate facets occupying full width of radials; anal X in notch between posterior radials, generally not visible from side. Arms ten, biserial except in lower portions, branching on axillary first primibrachs. Stem transversely round.

<==Paradelocrinidae [Atokacrininae]
|--Paradelocrinus Moore & Plummer 1938ML78
| `--*P. aequabilis Moore & Plummer 1938ML78
|--Lopadiocrinus Wanner 1916ML78
| `--*L. granulatus Wanner 1916ML78
|--Neocatacrinus Knapp 1969ML78
| `--*N. protensus (Moore & Plummer 1940) [=Paradelocrinus protensus]ML78
|--Sublobalocrinus Knapp 1969ML78
| `--*S. iolaensis (Strimple 1949) [=Paradelocrinus iolaensis]ML78
`--Atokacrinus Knapp 1969ML78
|--*A. obscurus Knapp 1969ML78
`--A. decorusML78

*Type species of generic name indicated

References

[ML78] Moore, R. C., N. G. Lane, H. L. Strimple, J. Sprinkle & R. O. Fay. 1978. Inadunata. In: Moore, R. C., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt T. Echinodermata 2. Crinoidea vol. 2 pp. T520–T759. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

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