Agassizocrinacea

Cup of Paragassizocrinus tarri, from here.

Belongs within: Dendrocrinida.

The Agassizocrinacea are a group of crinoids known from the Lower Carboniferous to Upper Permian (Moore et al. 1978).

Characters (from Moore et al. 1978): Crown cylindrical to pear-shaped. Cup bowl-shaped with convexly round base; infrabasals five or fused into single solid plate; readily visible from side; radial articular facets wide, occupying full width of radial summits; anal plates in cup none to four, joined very tightly in some to few lower posterior sac plates so as to form in effect upward projection of cup margin. Anal sac variably weak to strong, cylindrical or mushroom-shaped. Arms mostly numerous, isotomously branched on primaxils and heterotomously above. Stem transversely round or exceptionally pentagonal or pentalobate.

Agassizocrinacea
|--Cricocrinus Strimple & Watkins 1969 [Cricocrinidae]ML78
| `--*C. regulatus (Strimple 1949) [=Paradelocrinus regulatus]ML78
|--Trimerocrinus Wanner 1916 [Trimerocrinidae]ML78
| |--*T. pumilus Wanner 1916ML78
| `--T. ventricosusML78
|--BursacrinidaeML78
| |--Bursacrinus Meek & Worthen 1861ML78
| | `--*B. wachsmuthi Meek & Worthen 1861ML78
| |--Lebetocrinus Kirk 1940ML78
| | `--*L. grandis Kirk 1940ML78
| `--Nactocrinus Kirk 1947ML78
| `--*N. nitidus Kirk 1947ML78
|--Agassizocrinidae [Paragassizocrinidae]ML78
| |--Anartiocrinus Kirk 1940ML78
| | `--*A. lyoni Kirk 1940ML78
| |--Epipetschoracrinus Yakovlev in Yakovlev & Ivanov 1956ML78
| | `--*E. borealis Yakovlev in Yakovlev & Ivanov 1956ML78
| |--Petschoracrinus Yakovlev 1928ML78
| | `--*P. variabilis Yakovlev 1928ML78
| |--Agassizocrinus Owen & Shumard 1852 [incl. Agassizocrinites Troost 1850 (n. n.), Astylocrinus Roemer 1854]ML78
| | |--*A. conicus Owen & Shumard 1852ML78
| | `--A. laevis (Roemer 1854) [=*Astylocrinus laevis]ML78
| `--Paragassizocrinus Moore & Plummer 1940ML78
| |--*P. tarri (Strimple 1938) [=Agassizocrinus tarri]ML78
| `--P. kendrickensisML78
`--SundacrinidaeML78
|--Sundacrinus Wanner 1916ML78
| `--*S. granulatus Wanner 1916ML78
|--Basleocrinus Wanner 1916ML78
| `--*B. pocillum Wanner 1916ML78
|--Hemiindocrinus Yakovlev 1926ML78
| `--*H. fredericksi Yakovlev 1926ML78
|--Laccocrinus Wanner 1949ML78
| `--*L. scrobiculatus (Wanner 1924) [=Basleocrinus scrobiculatus]ML78
|--Parindocrinus Wanner 1937ML78
| `--*P. oyensi Wanner 1937ML78
`--Tribrachyocrinus M’Coy 1847 [=Tribrachiocrinus Wachsmuth & Springer 1886]ML78
|--*T. clarkii M’Coy 1847 [=*Tribrachiocrinus clarkii]ML78
|--T. corrugatus Ratte 1884F71
|--T. granulatus Etheridge 1892F71
`--T. ornatus Etheridge 1892F71

*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.

[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).

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