Gasterocomidae

Gasterocoma sp., from Steinkern.de.


Belongs within: Cyathocrinida.

The Gasterocomidae are a group of crinoids known from the Lower and Middle Devonian (Moore et al. 1978).

Characters (from Moore et al. 1978): Theca conical bowl shaped to globose; infrabasals five, three, or one; radial articular facets narrow horseshoe shaped; axial canal present; radianal absent, anal X present or absent, anal opening generally through side of cup below posterior radials. Anal sac absent. Moderately thick uniserial arms spread sideward, branching isotomously. Transversely round to quadrangular stem with axial and three or four peripheral canals.

Gasterocomidae [Gastrocomidae, Schultzicrinidae]
    |--Scoliocrinus Jaekel 1895 ML78
    |    `--*S. eremita Jaekel 1895 ML78
    |--Nanocrinus Müller 1856 ML78
    |    `--*N. paradoxus Müller 1856 ML78
    |--Schultzicrinus Springer 1911 ML78
    |    `--*S. typus Springer 1911 ML78
    |--Kopficrinus Goldring 1954 ML78
    |    `--*K. pustuliferus Goldring 1954 ML78
    |--Mictocrinus Goldring 1923 ML78
    |    `--*M. robustus Goldring 1923 ML78
    |--Gasterocoma Goldfuss 1839 (see below for synonymy) ML78
    |    |--*G. antiqua Goldfuss 1839 [=*Gastrocoma antiqua] ML78
    |    `--G. bicaula N79
    `--Myrtillocrinus Sandberger & Sandberger 1856 [incl. Tripleurocrinus Wood 1904] ML78
         |--*M. elongatus Sandberger & Sandberger 1856 ML78
         |--M. americanus ML78
         `--‘*Tripleurocrinus’ levis Wood 1904 ML78

Gasterocoma Goldfuss 1839 [=Gastrocoma Beyrich 1871; incl. Ceramocrinus Müller 1855, Epactocrinus Müller 1855] ML78

*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).

[N79] Norris, A. W. 1979. Devonian in the Western Hemisphere. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A218–A253. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

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