Dichocrinidae

Dichocrinus cinctus, from Fossilcrinoids.com.
Belongs within: Compsocrinina.

The Dichocrinidae are a group of crinoids known from the Carboniferous and Permian periods that commonly bore hypertrophied wing plates on the tegmen (Ubaghs 1978b).

Characters (from Ubaghs 1978b): Calyx small; basals two, equal, with ACD interbasal suture; radials five, separated on posterior side by primanal. Tegmen variable in height and prominence, with hypertrophied wing plates, or secondarily simplified to five orals. Free arms primitively uniserial and two to each ray, becoming biserial and four to six in each ray in advanced forms. Stem round transversely and straight, or coiled and bilateral.

<==Dichocrinidae [Dichocrininae, Talarocrininae]
|–Strimplecrinus Broadhead 1981 WM03
|    `–S. dyerensis WM03
|–Neodichocrinus Wanner 1937 U78b
|    `–*N. nanus Wanner 1937 U78b
|–Paradichocrinus Springer 1926 U78b
|    `–*P. polydactylus (Casseday & Lyon 1862) [=Dichocrinus polydactylus] U78b
|–Stomiocrinus Wanner 1937 U78b
|    `–*S. subglobosus Wanner 1937 U78b
|–Talarocrinus Wachsmuth & Springer 1881 U78b (see below for synonymy)
|    |–*T. cornigerus (Shumard 1857) [=Dichocrinus cornigerus] U78b
|    `–T. patei U78b
|–Camptocrinus Wachsmuth & Springer 1897 U78b
|    |–*C. myelodactylus Wachsmuth & Springer 1897 U78b
|    |–C. compressus U78a
|    |–C. crawfordvillensis U78a
|    `–C. multicirrus U78a
|–Pterotocrinus Lyon & Casseday 1859 (see below for synonymy) U78b
|    |–*P. capitalis (Lyon 1857) [=Asterocrinus capitalis] U78b
|    |–P. bifurcatus U78b
|    |–P. coronarius U78b
|    |–P. pyramidalis U78a
|    `–P. spatulus BL78
`–Dichocrinus Münster 1839 WM03 (see below for synonymy)
|–*D. radiatus Münster 1839 [=*Dichocrinites radiatus] U78b
|–D. angustus U78a
|–D. cinctus (Miller & Gurley 1896) WM03
|–D. crassitestus U78b
|–D. douglassi (Miller & Gurley 1890) WM03
|–D. labyrinthus Webster, Maples et al. 2003 WM03
|–‘Platycrinus’ ornatus M’Coy 1844 [=*Edwardsocrinus ornatus, Edwarsocrinus ornatus] U78b
|–*Cotyledonocrinus’ pentalobus Casseday & Lyon 1862 U78b
|–D. recurvibrachiatus U78a
`–D. shamsensis Webster, Maples et al. 2003 WM03

Dichocrinus Münster 1839 WM03 [=Dichocrinites Geinitz 1846 U78b; incl. Cotyledonocrinus Casseday & Lyon 1862 U78b, Edwardsocrinus d’Orbigny 1850 U78b, Edwarsocrinus U78b]

Pterotocrinus Lyon & Casseday 1859 [incl. Asterocrinus Lyon 1857 non Münster 1839, Codonocrinites Troost 1850 (n. n.), Codonocrinus Shumard 1868] U78b

Talarocrinus Wachsmuth & Springer 1881 U78b [incl. Daemenocrinites Troost 1850 (n. n.) U78b, Daemenocrinus Bather in Lankester 1900 (n. n.) U78b, Doliolocrinites Troost in Hall 1858 (n. n.) U78b, Doliocrinites Shumard 1866 A78, Doliolocrinus Wachsmuth & Springer 1881 (n. n.) U78b]

*Type species of generic name indicated

REFERENCES

[A78] Anon. 1978. Unassigned taxa. In: Moore, R. C., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt T. Echinodermata 2. Crinoidea vol. 3 p. T928. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[BL78] Breimer, A., & N. G. Lane. 1978. Ecology and paleoecology. In: Moore, R. C., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt T. Echinodermata 2. Crinoidea vol. 1 pp. T316–T347. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[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] Webster, G. D., C. G. Maples, R. Mawson & M. Dastanpour. 2003. A cladid-dominated Early Mississippian crinoid and conodont fauna from Kerman Province, Iran and revision of the glossocrinids and rhenocrinids. Journal of Paleontology 77 (Suppl. 3): 1–35.

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