Echinoderm Faunas of the Decatur Limestone and Ross Formation Upper Silurian to Lower Devonian of West central Tennessee

Taxonomy and paleoecology of the Silurian myelodactylid crinoid
Crinobrachiatus brachiatus ( Hall ) . Royal Ontario Museum Life Sciences
Contribution 141 : 11 pp . Eckert , J. D. , & C. E. Brett . 2001. Early Silurian (
Llandovery ) crinoids ...

Author: Craig Robert Clement

Publisher:

ISBN: 9780877105084

Category: Echinodermata

Page: 118

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Early Silurian Llandovery Crinoids from the Lower Clinton Group Western New York State

Two species of disparid Eomyelodactylus, E. sparteus Eckert and E. uniformis Eckert, and one unusual camerate Stipatocrinus hulveri Eckert and Brett, have been previously described from the Reynales Limestone.

Author: James D. Eckert

Publisher:

ISBN: 9780877104520

Category: Crinoidea, Fossil

Page: 88

View: 521

Early Silurian (Llandovery) crinoids have been poorly known. The present paper describes 26 species and six unassigned columnal taxa of Early Silurian crinoids on the basis of new and well preserved fossils from the lower Clinton Group of western New York. The new material, comprising eighteen genera, and unclassified skeletal material, spans the late middle Llandovery to the latest Llandovery and has been derived from several lithostratigraphic units. The Reynales Formation (Acronian) contains the following new genera: Dynamocrinus, Thaerocrinus, Haptocrinus, and Prolixocrinus: new species include Dynamocrinus robusts, Thaerocrinus crenatus, Haptocrinus calvatus, Prolixocrinus nodocaudis and Macrostylocrinus sp. Two species of disparid Eomyelodactylus, E. sparteus Eckert and E. uniformis Eckert, and one unusual camerate Stipatocrinus hulveri Eckert and Brett, have been previously described from the Reynales Limestone. Compsocrinus relictus, Dendrocrinus ursae, and an unidentified camerate occur in the laterally equivalent Bear Creek Shale. New taxa from the Wolcott Limestone (lower Telychian) include the Atalocrinacea, new superfamily: Atalocrinidae, Callistocrinidae, and Anisocrinidae, new families: Callistocrinus, Tormosocrinus, Atalocrinus, Aclistocrinus, Kyphosocrinus, and Scapanocrinus, all new genera: and the species Callistocrinus tesselatus, Tormosocrinus furberi, Atalocrinus arctus, Aclistocrinus capistratus, Kyphosocrinus tetreaulti, Scapanocrinus muricatus, Myelodactylus linae, Euspirocrinus wolcottense, Dendrocrinus aphelos, D. bactronodosus, Haptocrinus sp., ?anisocrinid sp., and an unidentified flexible crinoid. Protaxocrinus anellus n. sp., and five unidentifed columnal types occur in the upper Telychian Willowvale Shale. Taxonomic revisions also necessitate reassignments of three previously described taxa. The disparid Macnamaratylus Bolton is synonymized with Eumelodactylus, the flexible crinoid Clidochirus americanus Springer is reassigned to Prolixocrinus n. gen. and the cladid genus Quinquecaudex Brower and Veinus, 1981, is synonymized with Dendrocrinus. The erroneous species, Glyptocrinus plumosus Hall is reviewed: the cotype specimens in part represent the cirral column of a myelodactylid disparid crionid, here tentatively assigned to Eomeyelodatylus (E. ? plumosus (Hall)); the remaining material consists of columnals and pluricolumnals probably belonging to Haptocrinus. Physically stressed, uncrowed environments of the Early Silurian in western New York were characterized by low diversity crinoid assemblages and provided a refuge for relictual Ordovician taxa that became extinct in the late Llandovery. Diverse assemblages of crinoids dominated by Wenlock precursors inhabited mixed carbonate-siliciclastic regimes distal to shoals. Early silurian crinoids of the Clinton Group are highly endemic in marked contrast to the generally low provincialism of other taxa (e.g., brachiopods) during this interval.


Phylogeny Speciation and Palaeoecology of the Early Carboniferous Mississippian Conodont Genus Mestognathus

MEYER , D. L. 1971 Post - mortem disarticulation of Recent crinoids and
ophiuroids under natural conditions . ... ECKERT , J. D. 1984 Early Llandovery
crinoids and stelleroids from the Cataract Group ( Lower Silurian ) in southern
Ontario ...

Author: Peter H. Von Bitter

Publisher:

ISBN:

Category: Science

Page: 114

View: 697

Mestognathus, an important Early Carboniferous conodont genus whose appearance has generally been thought to coincide with, and define, the base of the Visean, evolved from Clydagnathus during the Tournaisian and ranges from that stage into the Namurian. Five species, including M. harmalai sp. nov. and M. praebeckmanni sp. nov. , are distinguished by the gradual phyletic development of the parapet, the fixed blade, the anterior notch, the position of the carinal deflection, and the increasing tendency to evert the basal cavity. Mestognathus dhuensis and M. neddensis are demonstrated to be synonyms of M. beckmanni, M. bipluti, or Mestognathus spp.


Memoirs of the Queensland Museum

Pygmaeocrinus , a new crinoid from help in the field and with stratigraphy , Tom
the Devonian of Bohemia . Vestnik Kralovske Darragh , Museum ... Early
Llandovery crinoids and ryocrinus , Wenlock Limestone . Annals and stelleroids
from the ...

Author: Queensland Museum

Publisher:

ISBN:

Category: Ethnology

Page:

View: 285


Geobiology of Echinoderms

Podolithus , crinoid base , its use in recognition of Ordovician and Devonian
disconformities in eastern North America . ... Early Llandovery crinoids and
stelleroids from the Cataract Group ( Lower Silurian ) in southern Ontario ,
Canada .

Author: Johnny A. Waters

Publisher:

ISBN:

Category: Echinodermata

Page: 355

View: 696


Anthropological Field Studies

A field guide to the Silurian Echinodermata of the British Isles : part 2 - Crinoidea ,
minor groups and discussion . Proceedings of the Yorkshire Geological Society ,
57 . Eckert , J.D. 1984. Early Llandovery crinoids and stelleroids from the ...

Author:

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Category: Geology

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View: 966


Echinoderm Paleobiology

The systematic account of the Ordovician crinoids was published as a volume
essentially derived straight from the Ph.D. ... More importantly, Ramsbottom
provided the first systematic account of the British Llandovery crinoids, which
were ...

Author: William Irl Ausich

Publisher: Indiana University Press

ISBN: 0253351286

Category: Science

Page: 456

View: 794

Treats various paleobiological approaches to the phylum's remarkable evolutionary history


Bulletins of American Paleontology

82 , Donovan , S.K. , and Cope , J.P.C. 1989 . A new camerate crinoid from the
Arenig of south Wales . Palaeontology , vol . 32 , pp . 101-107 . Eckert , J. , and
Brett , C.E. 2001. Early Silurian ( Llandovery ) crinoids from the Lower Clinton
Group ...

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Category: Paleontology

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View: 427



Tectonic and Eustatic Controls on Sedimentary Cycles

35-61 . ECKERT , J. D. , 1984 , Early Llandovery crinoids and stelleroids from the
Cataract Group ( Lower Silurian ) in southern Ontario , Canada : Toronto , Royal
Ontario Museum Life Sciences Contribution 127 , AIGNER , T. , 1985 , Storm ...

Author: John M. Dennison

Publisher: Sepm Society for Sedimentary

ISBN:

Category: Science

Page: 264

View: 409

The collected volume begins with a brief perspective by one of the conveners, followed by articles in order of increasing stratigraphic age. Eustatic sea-level changes and tectonic warpings of basins are competing mechanisms for explaining many stratigraphic patterns. The model for sea-level changes should be developed first for a basin, since it is allocyclic and leads to a series of time bands in the strata. The residual effects should then be modeled for tectonic patterns affecting the depositional processes. Doing the reverse limits time constraints on the tectonic warping models and will blur the resolution of detailed time surfaces in the strata. Case histories of situations with both tectonic warping and time surfaces marked by sea-level events will lead to improved interpretations of earth history.

A New Llandovery early Silurian Conodont Biozonation and Conodonts from the Becscie Merrimack and Gun River Formations Anticosti Island Qu bec

Schönlaub (in Sweet and Schönlaub, 1975) reconstructed the apparatus of
Oulodus jeannae from the Llandovery crinoid limestone in Western Karawanken
Alps, Austria. Although he considered that the Pa, Pb, M, Sa, Sb, and Sc
elements ...

Author: Shunxin Zhang

Publisher:

ISBN:

Category: Anticosti Island (Québec)

Page: 46

View: 266



Contributions from the Museum of Paleontology

Early Llandovery crinoids and stelleroids from the Cataract Group ( Lower
Silurian ) in southern Ontario , Canada . Royal Ontario Museum Life Sciences
Contributions , 137 : 1-83 . 31. Eckert , J. D. 1987. Nlemocrinus amphiatus , a
new cladid ...

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Category: Geology

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Canadian Journal of Earth Sciences

Reefs are also noticeably missing in the lower 300 m of the succeeding
Llandovery strata ( until the East Point Mbr ) ... and early part of the Aeronian
yielded very few specimens ( low abundance , low diversity ) , yet Elrodooceras
and Donacoceras appeared in the latter . ... In the mid- to late Telychian , reefal
and perireefal , crinoid meadow - dominated Chicotte Fm , both Billings ( 1857a )
and Foerste ...

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Category: Geology

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View: 229


Studies in Geology

Petalocrinus is known to range from the late Llandovery to middle Wenlock ,
whereas Scyphocrinites ranges throughtout the Silurian into early Devonian (
Llandovery - Lockov ) ( Witzke et al . , 1979 , p . 126 ) . ** Crinoids play a
subordinate ...

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Category: Geology

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View: 172