Sycocrinitidae

Reconstruction of Monobrachiocrinus granulatus, from Moore et al. (1978).

Belongs within: Cyathocrinida.

The Sycocrinitidae are a group of crinoids with a globular theca bearing a single arm, known from the Carboniferous and Permian periods (Moore et al. 1978).

Characters (from Moore et al. 1978): Theca with one arm-bearing radial; other radials present or absent, commonly unequal and reduced in size; infrabasals three; anal X plate absent; anal opening bounded by basals and radials, or by radials. Orals small, commonly not preserved.

Sycocrinitidae
    |--Sycocrinites Austin & Austin 1842 [=Sycocrinus Morris 1843] ML78
    |    `--*S. anapeptamenus Austin & Austin 1842 [=*Sycocrinus anapeptamenus] ML78
    |--Allosycocrinus Wanner 1924 ML78
    |    `--*A. pusillus Wanner 1924 ML78
    |--Metasycocrinus Wanner 1920 ML78
    |    `--*M. pyriformis (Rothpletz 1892) [=Hypocrinus pyriformis] ML78
    |--Parasycocrinus Marez Oyens 1940 ML78
    |    `--*P. fastigatepileatus Marez Oyens 1940 ML78
    `--Monobrachiocrinus Wanner 1916 ML78
         |--*M. ficiformis Wanner 1916 ML78
         |--M. granulatus ML78 [=M. ficiformis granulatus U78]
         `--M. oviformis BLWR78

*Type species of generic name indicated

REFERENCES

[BLWR78] Brower, J. C., N. G. Lane & H. Wienberg Rasmussen. 1978. Postlarval ontogeny of fossil crinoids. In: Moore, R. C., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt T. Echinodermata 2. Crinoidea vol. 1 pp. T244–T274. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[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).

[U78] Ubaghs, G. 1978. Skeletal morphology of fossil crinoids. In: Moore, R. C., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt T. Echinodermata 2. Crinoidea vol. 1 pp. T58–T216. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).