Dolatocrinidae

Calyx of Dolatocrinus lacus in (left to right) A-ray, basal and tegminal views, from Ubaghs (1978).

Belongs within: Glyptocrinina.

The Dolatocrinidae are a group of crinoids known from the Lower to Middle Devonian that commonly exhibit a markedly pentaradial calyx (Ubaghs 1978).

Characters (from Ubaghs 1978): Basals three, unequal or commonly fused; fixed primibrachs one or two and fixed secundibrachs one to seven in each ray; brachitaxes as far as fixed quartibrachs may be incorporated in calyx, which tends to acquire perfect pentameral symmetry; interradials not exceeding three or four ranges, first one large, none to two next above, extra interprimibrachs sometimes present in CD interray; intersecundibrachs and intertertibrachs rarely developed. Tegmen stout, wih or without anal tube. Free arms simple or branching, composed of biserial or compound brachials. Column cylindrical, relatively large, may be lateral flanges.

Dolatocrinidae [Dolatocrinites]
    |–Comanthocrinus Springer 1921 U78
    |    `–*C. indianensis (Miller & Gurley 1897) [=Stereocrinus indianensis] U78
    |–Craterocrinus Goldring 1923 U78
    |    `–*C. ruedemanni Goldring 1923 U78
    |–Clarkeocrinus Goldring 1923 U78
    |    |–*C. troosti (Hall 1862) [=Cacabocrinus troosti] U78
    |    `–C. spriesterbachi U78
    `–Dolatocrinus Lyon 1857 (see below for synonymy) U78
         |–*D. lacus Lyon 1857 U78
         |–D. exculptus U78
         |–D. grandis U78
         `–‘*Stereocrinus’ triangulatus Barris 1878 U78

Dolatocrinus Lyon 1857 [incl. Cacabocrinites Troost 1850 (n. n.), Cacabocrinus Hall 1862, Stereocrinus Barris 1878] U78

*Type species of generic name indicated

REFERENCES

[U78] Ubaghs, G. 1978. Camerata. In: Moore, R. C., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt T. Echinodermata 2. Crinoidea vol. 2 pp. T408–519. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

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