XVIII.—Proposed Arrangement of the Echinodermata, particularly as regards the Crinoidea and a Subdivision of the Class Adelostella (Echinidæ)

“…This is probably an Early Carboniferous specimen because it is from Fremington, which is south of the Taw estuary. Family PLATYCRINITIDAE Austin and Austin, 1842 Genus PLATYCRINITES Miller, 1821 Platycrinites sp.…”

mentioning

confidence: 99%

Revision Of Late Devonian (Famennian) And Some Early Carboniferous (Tournaisian) Crinoids And Blastoids From The Type Devonian Area Of North Devon

2001

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ABSTRACT. The crinoids and blastoids from the Pilton (Beds) Formation of the type Devonian of north Devonshire are revised. These fossils were monographed by the Rev. G. F. Whidborne in 1898, but have not been studied since that time. Recent studies on various groups of fossils from the Pilton and related rocks in North Devon con®rm that the great majority of these fossils are Famennian, although three specimens from Fremington are probably Early Carboniferous (Tournaisian). We identify four blastoid taxa from a fauna that is sparse and poorly preserved; two spiraculates, one ®ssiculate, and one taxon unidenti®able at the ordinal level. Mesoblastus cf. M. crenulatus from the Gattendor®a Zone (Lower Carboniferous) near Fremington is the oldest known representative of this genus. The crinoid fauna is somewhat more diverse, but the preservation is equally poor. No changes are made in the¯exible crinoids. Among camerate crinoids, one species is reassigned to Eumorphocrinus and one is retained in Actinocrinites. Specimens of some crinoids, such as Rhodocrinites and Megistocrinus, are so poorly preserved that certain identi®cation was not possible. The hexacrinoid Adelocrinus, relegated to uncertainty for 150 years, is here shown to be a valid genus that is very similar to Arthroacantha, but not synonymous with it. Among the cladid crinoids, the dominant groups are those within the Superfamily Scytalocrinacea, which includes Bridgerocrinus, Sostronocrinus, and Scytalocrinus, all of which are placed in the new family Sostronocrinidae. One new species, Glossocrinus whidbornei, is named. Non-pinnulate cladids, common in older Devonian rocks, do not occur. The fauna shows considerable similarity with faunas from eastern North America and Germany. It shows less resemblance to the extensive Famennian crinoid and blastoid fauna of north-western China, despite some remarkable congruencies, especially the occurrence of very similar species of Actinocrinites in these widely separated areas.

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“…Order MONOBATHRIDA Moore and Laudon, 1943 Suborder COMPSOCRININA Ubaghs, 1978bSuperfamily PERIECHOCRINOIDEA Bronn, 1849 Family ACTINOCRINITIDAE Austin and Austin, 1842 Subfamily ACTINOCRININAE Austin and Austin, 1842 Genus ACTINOCRINITES Miller, 1821 Type species.Actinocrinites triacontadactylus Miller, 1821, by subsequent designation of Wachsmuth and Springer, 1881. ACTINOCRINITES EXIMIUS (Kirk, 1943) Actinocrinus eximius KIRK, 1943, p. 264. Actinocrinus griffithi WACHSMUTH AND SPRINGER, 1897, p. 568, pl.…”

Section: Rhodocrinites Barrisi Divergensmentioning

confidence: 99%

Crinoids From the Nada Member of the Borden Formation (Lower Mississippian) in Eastern Kentucky

Lee

Ausich

Kammer

2005

Journal of Paleontology

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Thirty-four crinoid species, including four new species, are reported from the Nada Member of the Borden Formation in eastern Kentucky. The dominant crinoid group is monobathrids (18 species), but diplobathrids, disparids, cladids, and flexibles are also present. The four new species are the camerates Blairocrinus protuberatus, Uperocrinus acuminatus, and Aorocrinus nodulus, and the cladid Atelestocrinus kentuckyensis. The majority of the species in this fauna were previously known from what has traditionally been considered the ''upper part'' of the Burlington Limestone in the Mississippi River Valley and what is now recognized as the Burlington Pelmatozoan Assemblage III. The current study confirms the conclusion of Lane and DuBar (1983) that the Nada is middle Osagean in age, being deposited earlier than the well-documented Borden delta crinoid assemblages of north-central Kentucky and Indiana. The middle Osagean age of the fauna indicates a previously unrecognized unconformity between the Nada and the overlying Meramecianage Renfro Member of the Slade Formation. In addition, this is the first well-documented middle Osagean fauna from a siliciclastic facies in North America. The dominance by camerate crinoids is enigmatic, but may be related to either a low rate of sedimentation or greater larval dispersal abilities.

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XVIII.—Proposed Arrangement of the Echinodermata, particularly as regards the Crinoidea and a Subdivision of the Class Adelostella (Echinidæ)

Cited by 52 publications

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Crinoids from the Silurian of Western Estonia

Crinoids from the Silurian of Western Estonia

Revision Of Late Devonian (Famennian) And Some Early Carboniferous (Tournaisian) Crinoids And Blastoids From The Type Devonian Area Of North Devon

Crinoids From the Nada Member of the Borden Formation (Lower Mississippian) in Eastern Kentucky

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