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 1940 ML78
    |    `–*B. texanus Moore & Plummer 1940 ML78
    |–Celonocrinus Lane & Webster 1966 ML78
    |    `–*C. expansus Lane & Webster 1966 ML78
    |–Heliosocrinus Strimple 1951 ML78
    |    `–*H. aftonensis Strimple 1951 ML78
    |–Pedinocrinus Wright 1951 ML78
    |    `–*P. clavatus (Wright 1937) [=Pachylocrinus clavatus] ML78
    |–Rhopocrinus Kirk 1942 ML78
    |    `–*R. spinosus Kirk 1942 ML78
    |–Brabeocrinus Strimple & Moore 1971 ML78
    |    |–*B. christinae Strimple & Moore 1971 ML78
    |    `–B. cuneatus ML78
    `–Stellarocrinus Strimple 1940 (see below for synonymy) ML78
         |–*S. stillativus (White 1880) [=Cyathocrinus stillativus, *Whiteocrinus stillativus] ML78
         |–S. bilineatus ML78
         |–S. florealis ML78
         |–S. geometricus (Moore & Plummer 1940) [=*Apollocrinus geometricus] ML78
         `–S. virgilensis ML78

Stellarocrinus Strimple 1940 [=Whiteocrinus Strimple 1939 non Jaekel 1918; incl. Apollocrinus Moore & Plummer 1940]

*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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