Crinoid Paleoecology
Geology 632: Paleoecology Echinoderms: 21 classes (16 extinct) including: • Crinoids •Blastoids • Cystoids • Edrioasteroids •Asteroids • Ophiuroids • Echinoids • Holothurians Crinoid Blastoid Cystoid Edrioasteroid Asteroid Ophiuroid Echinoids: sand dollar (left) sea biscuit (below) Holothurian: sea cucumber Classification of Crinoids
• Paleozoic Crinoids – Subclass Camerata: pinnulate arms – Subclass Disparida: nonpinnulate arms – Subclass Cladida: pinnulate and nonpinnulate – Subclass Flexibilia: nonpinnulate arms • Mesozoic and Cenozoic Crinoids – Subclass Articulata: pinnulate arms • Isocrinids - stalked • Comatulids - free living Examples of Mississippian Crinoid Clades
A. Camerate crinoid with pinnulate arms. Abatocrinus grandis
B. Disparid crinoid with non- pinnulate arms. Synbathocrinus swallovi
C. Advanced cladid crinoid with pinnulate arms. Decadocrinus tumidulus
D. Primitive cladid crinoid with non-pinnulate arms. Cyathocrinites barydactylus
E. Flexible crinoid with non- pinnulate arms. Onychocrinus ulrichi Actinocrinites: a camerate; note the pinnulate arms Cyathocrinites, a primitive cladid with nonpinnulate arms Actinocrinites and Barycrinus, Mississippian Diversity of crinoid genera over geologic time. High modern diversity is a taphonomic artifact. Encrinus, the survivor of the Permian extinction event, founder of the Articulata Endoxocrinus at a depth of 692 m, Bahamas Cenocrinus, 310 m, Bahamas Endoxocrinus, 430 m, Bahamas Endoxocrinus and ophiuroids, 573 m, Bahamas Neocrinus, 424 m, Bahamas Neocrinus, 424 m, Bahamas. Current = 20cm/s Neocrinus, 424 m, Bahamas Tube feet on the pinnules of crinoid arms Modern comatulid crinoids, Bahamas Modern comatulid crinoids, Bahamas Living basketstar: convergent evolution on Paleozoic nonpinnulate crinoids
Crinoid Faunas Osagean-Meramecian stratigraphy and time intervals for crinoids MDS Plot, K&A, 1987, Table 1 data (species counts)
14.KYSo lite Low Energy 0.4 Facies
0.3 13 . B M K
0.2 2 e t
0.1 High Energy
Coordina 11. B o yS c o u t Facies 12.A llensC rk 0 10.Waldrip 8.L.Quar4.rWy arsaw 9.IndianCrk 15.WhitesCrk 7.U.Quarry 2.ClarkCo. -0.1 3.Keokuk
1. B o o n v i 6.l l eHamilton Carbonate Facies -0.2
5.Nauvoo Stress = 0.06 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 Coordinate 1 CA Plot, K&A, 1987, Table 1 data (species counts)
0.018
FLEX 0.012 Low Energy 14 . K Y S o l i t e Facies
0.006 13 . B M K DISPAR CYATHO = PRIM. CLADIDS
0 POTER 10 . W a l d r i p = ADV. CLADIDS 2 is 7.U.Quarry
-Ax 0.006 11.BoyScout 9.IndianCrk 12.A8.llLe.nQsuCarrkry High Energy
-0.012 Facies
MONO 4.Warsaw 2.ClarkCo.
-0.018 15.WhitesCrk 6.Hamilton 1.Boonville 5.Nauvoo 3.Keokuk Carbonate -0.024 Facies
-0.03 -0.024 -0.016 -0.008 0 0.008 0.016 0.024 0.032 0.04
A xis 1 New Providence Shale at Button Mold Knob, near Louisville, KY. Low-energy facies. First Paleozoic fossils west of the Appalachians were collected here in 1816. Crinoidal debris weathering from the New Providence Shale, Kentucky Crinoid stem in the New Providence Shale, KY The lower Warsaw Fm., Keokuk, Iowa. Mixed carbonates and clastics. Mississippian limestone bluffs along the Mississippi River in Illinois. Carbonate platform. Burlington and Keokuk limestones, Iowa. Carbonate platform environment. Crinoidal bioherm, Fort Payne Fm., Kentucky. Organic carbonate buildups. Crinoidal limestone, Fort Payne Fm. Crinoid calyces in the Fort Payne Fm. Upper Warsaw Fm., St. Louis, MO. Cross- bedded limestones: high energy environment Closeup of cross-bedded limestones. Examples of Mississippian crinoids: various species of Cyathocrinites, a nonpinnulate cladid Examples of Mississippian crinoids: various species of Barycrinus, a nonpinnulate cladid Various species of pinnulate cladid crinoids Various species of pinnulate cladid crinoids The camerate crinoid Agaricocrinus The camerate crinoid, Dizygocrinus