Platycrinitidae

Platycrinites saffordi, from U. S. National Museum of Natural History.

Belongs within: Glyptocrinina.

The Platycrinitidae are a group of crinoids known from the Upper Silurian or Devonian to the Permian (Ubaghs 1978b).

Characters (from Ubaghs 1978b): Calyx confined to patina of five radials, and three unequal basal which may be fused; posterior side commonly not differentiated; orals distinct; interambulacrals and ambulacrals important tegminal elements but absent in youngest genera; first primibrachs typically axillary. Arms biserial, pinnulate. Column transversely round proximally, elliptical and twisted distally, with synarthrial articulation, fulcral ridge following long diameter of columnals; axial canal small, round.

Platycrinitidae [Platycrinidae, Platycrinoidea]
|--Neoplatycrinus Wanner 1916U78b
| `--*N. dilatatus Wanner 1916U78b
|--Brahmacrinus Sollas 1900U78b
| `--*B. ponderosus Sollas 1900U78b
|--Plemnocrinus Kirk 1946U78b
| `--*P. beebei Kirk 1946U78b
|--Oenochoacrinus Breimer 1962U78b
| |--*O. princeps Breimer 1962U78b
| `--O. pileatusU78a
|--Chinacrinus Lane, Waters & Maples 1997WM03
| |--C. nodosusWM03
| `--C. xinjiangensis Lane, Waters & Maples 1997WM03
|--Pleurocrinus Austin & Austin 1843 [=Medusacrinus Austin 1875]U78b
| |--*P. mucronatus (Austin in Austin & Austin 1843) [=Platycrinites mucronatus, *Medusacrinus mucronatus]U78b
| `--P. coronatusU78b
|--Eucladocrinus Meek 1872U78b
| |--*E. montanaensis (Meek 1872) [=Platycrinites (Eucladocrinus) montanaesis]U78b
| |--E. millebrachiatusU78a
| | |--E. m. millebrachiatusU78a
| | `--E. m. immaturusU78a
| `--E. pleuroviminusU78b
`--Platycrinites Miller 1821LMW01 (see below for synonymy)
|--*P. laevis Miller 1821U78b [=*Platycrinus laevisU78b; incl. Platycrinus vexabilis White 1877W77]
|--P. anguliferus (Whidborne 1898) (n. d.) [=Platycrinus anguliferus]LMW01
|--P. austinianusU78a
|--P. bozemanensisU78a
|--P. burlingtonensisU78b
|--P. gigas Gilbertson in Phillips 1836 [=*Centrocrinus gigas]U78b
|--P. guttifer Schmidt 1930LMW01
|--P. hemisphericusU78a
|--*Atocrinus’ milleri M’Coy in Griffith 1842U78b
|--‘Platycrinus’ nux Etheridge 1892F71
|--P. regalisU78a
|--P. saffordiU78b
`--P. symmetricusU78a

Platycrinites Miller 1821LMW01 [=Platycrinus Agassiz 1836U78b; incl. Atocrinus M’Coy in Griffith 1842U78b, Centrocrinus Austin & Austin 1843U78b]

*Type species of generic name indicated

References

[F71] Fletcher, H. O. 1971. Catalogue of type specimens of fossils in the Australian Museum, Sydney. Australian Museum Memoir 13: 1–167.

[LMW01] Lane, N. G., C. G. Maples & J. A. Waters. 2001. Revision of Late Devonian (Famennian) and some Early Carboniferous (Tournaisian) crinoids and blastoids from the type Devonian area of north Devon. Palaeontology 44 (6): 1043–1080.

[U78a] Ubaghs, G. 1978a. 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).

[U78b] Ubaghs, G. 1978b. Camerata. In: Moore, R. C., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt T. Echinodermata 2. Crinoidea vol. 2 pp. T408–T519. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[WM03] Waters, J. A., C. G. Maples, N. G. Lane, S. Marcus, Liao Z.-T., Liu L., Hou H.-F. & Wang J.-X. 2003. A quadrupling of Famennian pelmatozoan diversity: new Late Devonian blastoids and crinoids from northwest China. Journal of Paleontology 77 (5): 922–948.

[W77] White, C. A. 1877. Report upon the invertebrate fossils collected in portions of Nevada, Utah, Colorado, New Mexico, and Arizona, by parties of the expeditions of 1871, 1872, 1873, and 1874. U.S. Geographical Surveys West of the One Hundredth Meridian 4 (1): 1–219, pls 1–21.

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