Melocrinitidae

Melocrinites sp., copyright James St. John.

Belongs within: Glyptocrinina.

The Melocrinitidae are a group of crinoids known from the Upper Ordovician to the Upper Devonian (Ubaghs 1978b).

Characters (from Ubaghs 1978b): Secundibrachs two or three in each ray, rarely more; interprimibrachs merging with tegmen; presence of intersecundibrachs and intertertibrachs dependent on degree of brachial incorporation in calyx; primanal generally followed by median row of anal plates; anal tube may be present. Free arms four in each ray, undivided or exotomously branching; inner pair of arms primitively distinct, secondarily fusing into stout biserial ramuli-bearing trunk; outer pair progressively reduced and disappearing in ultimate members. Column with sharply defined nodals and internodals.

Melocrinitidae [Ctenocrinidae, Melocrinidae]
    |–Alisocrinus Kirk 1929 U78b
    |    |–*A. warreni (Ringueberg 1888) [=Mariacrinus warreni] U78b
    |    `–A. tetrarmatus Brower 1973 EB01
    |–Trichotocrinus Olsson 1912 U78b
    |    |–*T. harrisi (Olsson 1912) [=Melocrinus (Trichotocrinus) harrisi] U78b
    |    |–T. lutheri U78b
    |    `–T. terranovicus U78a
    |–Promelocrinus Jaekel 1902 (see below for synonymy) U78b
    |    |–*P. anglicus Jaekel 1902 U78b
    |    |–P. fulminatus U78b
    |    |–*Zenkericrinus’ melocrinoides Waagen & Jahn 1899 U78b
    |    `–P. radiatus U78a
    |–Ctenocrinus Bronn 1840 (see below for synonymy) U78b
    |    |–*C. typus Bronn 1840 [=*Ctenocrinites typus] U78b
    |    |–*Clonocrinus’ bigsbyi Oehlert 1879 U78b
    |    |–C. gottlandicus (Pander in Helmersen 1858) U78b (see below for synonymy)
    |    |–C. nobilissimus (Hall 1859) U78a, U78b [=*Mariacrinus nobilissimus U78b]
    |    |–*Astrocrinites’ pachydactylus Conrad 1841 [=*Astrocrinus pachydactylus] U78b
    |    `–‘Periechocrinus’ radiatus [=Lindstroemiocrinus radiatus] J18
    `–Melocrinites Goldfuss 1831 (see below for synonymy) U78b
         |–*M. hieroglyphicus Goldfuss 1831 [=*Melocrinus hieroglyphicus] U78b
         |–M. aequus U78b
         |–*Kuzbassocrinus’ bystrowi Yeltysheva 1957 U78b
         |–M. gibbosus Goldfuss 1831 [=*Castanocrinus gibbosus] U78b
         |–M. gracilis EB01
         |–M. micmac BL78
         |–M. pulcher U78a
         `–M. splendens U78a

Ctenocrinus Bronn 1840 [=Ctenocrinites Steininger 1849; incl. Astrocrinites Conrad 1841, Astrocrinus Bather 1900 non Morris 1843, Clonocrinus Oehlert 1879 non Quenstedt 1876, Lindstroemiocrinus Jaekel 1918, Mariacrinus Hall 1859] U78b

Ctenocrinus gottlandicus (Pander in Helmersen 1858) U78b [=Trochocrinites gottlandicus U78b, *Lindstroemiocrinus gottlandicus U78b, Periechocrinus gottlandicus J18]

Melocrinites Goldfuss 1831 [=Melocrinus Agassiz 1836; incl. Castanocrinus Roemer 1855, Kuzbassocrinus Yeltysheva 1957] U78b

Promelocrinus Jaekel 1902 [incl. Proctenocrinus Jaekel 1918 (n. n.), Xenocrinus Jahn 1892 non Miller 1881, Zenkericrinus Waagen & Jahn 1899] U78b

*Type species of generic name indicated

REFERENCES

[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).

[EB01] Eckert, J. D., & C. E. Brett. 2001. Early Silurian (Llandovery) crinoids from the Lower Clinton Group, western New York State. Bulletins of American Paleontology 360: 1–88.

[J18] Jaekel, O. 1918. Phylogenie und System der Pelmatozoen. Paläontologische Zeitschrift 3: 1–128.

[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).

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