Stellarocrinidae

Stellarocrinus bilineatus, from here.

Belongs within: Dendrocrinida.

The Stellarocrinidae are a group of crinoids with a low, spreading crown known from the middle Carboniferous to the Upper Permian (Moore et al. 1978).

Characters (from Moore et al. 1978): Crown typically spreading sideward, low; arms well separated from neighbors. Cup medium to low bowl-shaped, commonly with broad, shallow basal concavity; infrabasals subhorizontal; basals large, usually protruded about basal depression; radials wider than long, articular facets not as wide as radials, strongly declivate, typically leaving well-marked interradial notches; cup anal plates three in normal to advanced arrangement with single anal plate (radianal) on CD basal, followed above cup by two equidimensional plates. Anal sac cylindrical, tall, composed of moderately large protuberant hexagonal plates in alternating vertical series. Arms strongly cuneate-uniserial to mostly biserial, not apposed, branching on primibrachs 1 in geologically younger forms, primibrachs 2 in older ones, with one or more subsequent branchings in all rays; pinnules stout, attached to inner surfaces of brachials. Column usually round, occasionally transversely pentastellate.

Stellarocrinidae
|--Brychiocrinus Moore & Plummer 1940ML78
| `--*B. texanus Moore & Plummer 1940ML78
|--Celonocrinus Lane & Webster 1966ML78
| `--*C. expansus Lane & Webster 1966ML78
|--Heliosocrinus Strimple 1951ML78
| `--*H. aftonensis Strimple 1951ML78
|--Pedinocrinus Wright 1951ML78
| `--*P. clavatus (Wright 1937) [=Pachylocrinus clavatus]ML78
|--Rhopocrinus Kirk 1942ML78
| `--*R. spinosus Kirk 1942ML78
|--Brabeocrinus Strimple & Moore 1971ML78
| |--*B. christinae Strimple & Moore 1971ML78
| `--B. cuneatusML78
`--Stellarocrinus Strimple 1940 [=Whiteocrinus Strimple 1939 non Jaekel 1918; incl. Apollocrinus Moore & Plummer 1940]ML78
|--*S. stillativus (White 1880) [=Cyathocrinus stillativus, *Whiteocrinus stillativus]ML78
|--S. bilineatusML78
|--S. florealisML78
|--S. geometricus (Moore & Plummer 1940) [=*Apollocrinus geometricus]ML78
`--S. virgilensisML78

*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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