Bulletins of American paleontology (Bull. Am. paleontol.) Vol 360

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u Begun in 1895 NUMBER 360 xMARCH Early Silurian (Llandovery) Crinoids from the Lower Clinton Group, Western New York by James D Eckert and Carlton Brett Paleontological Research Institution 1259 Trumansburg Road New Yorit, 14850 U.S.A ithaca State 1, 2001 PALEONTOLOGICAL RESEARCH INSTITUTION Officers Shirley K Egan President John Pojeta, Jr P Hartnett Henry W Theisen Patricia A Johnson First Vice-Presjdent Howard Second Vice-President Secretary Treasurer Director Warren D Allmon Trustees Philip Proujansky Carlton E Brett William L Crepet Michael Driscoll J Thomas Dutro, Jr W Megan D Shay Mary M Shuford Shirley K Egan Constance M Soja John C Steinmetz Harry G Lee Peter B Stifel Henry W Theisen Sally T True Christopher G Maples Arthur Waterman Howard P Patricia Haugen Amy R Hartnett McCune Trustees Emeritus Harry A Leffingwell Robert M Linsley Samuel T Pees Edward B Picou, Jr James E Sorauf Raymond Van Houtte William P S Ventress Thomas E Whiteley BULLETINS OF AMERICAN PALEONTOLOGY and PALAEONTOGRAPHICA AMERICANA Warren A D Allmon Editor both series, and available numbers and volumes may be had on request Volumes 1-23 of Bulletins ofAmerican Paleontology are available list of titles in from Periodicals Service Company, 11 Main St., Gemiantown, New York 12526 USA Volume of Palaeontographica Americana has been reprinted by Johnson Reprint Corporation, 1 Fifth Ave., New York NY 10003 USA Subscriptions to Bulletins of American Paleontology are available for US $150 per year (individual or institution) plus postage Issues are available and priced individually Numbers of Palaeontographica Americana are priced individually for additional information, write or call: Paleontological Research Institution 1259 Trumansburg Road Ithaca, NY 14850 USA (607) 273-6623 FAX (607) 273-6620 vvrww.priweb.org @ This paper meets the requirements of ANSI/NISO 239.48-1992 (Permanence of Paper) ^utktms of Jixucnt towqs) Begun NUMBER in 1895 MARCH 360 Early Silurian (Llandovery) Crinoids from the Lower Clinton Group, Western New York State by James D Eckert and MCZ LIBRARY :AR zrxf ^VARD UNIVHRSITY I-; Carlton E Brett Paleontological Research Institution 1259 Trumansburg Road New York, 14850 U.S.A Ithaca, Z001 r- 1, 2001 ISSN 0007-5779 ISBN 0-87710-452-2 Library of Coni^ress Control Number: 00-134801 Note: Beginning with issue number 356, Bulletins of American Paleontology is no longer designating volumes The journal will continue to publish approximately 2-4 issues per year, each of which will continue to be individually numbered Printed in the United States of America Allen Press, Inc Lawrence KS 66044 U.S.A CONTENTS page Abstract Acknowledgments 6 Introduction Stratigraphy of the lower CUnton Group in New York Age and Correlation Taphonomy and Paleoecology 11 Introduction 12 Rcynales Formation 12 Bear Creek Shale 14 Wolcott Limestone 14 Willowvale Shale 17 Diagenesis 18 Systematic Paleontology 19 Introduction Repositories 19 Systematics 19 Subphylum Crinozoa Class Crinoidea Subclass Camerata Order Diplobathrida Suborder Eudiplobathrina Superfamily Rhodocrinitacea Family Callistocrinidae Genus 20 gen Ciillisrocriniis n Family Emperocrinidae Genus Tunni'smrinus 22 gen n Order Monobathrida Suborder Compsocrinina Superfamily Xenocrinacea Family Tanaocrinidae Genus Compsocrinus 25 ?Suborder Compsocrinina Superfamily Atalocrinacea Family Atalocrinidae Genus Auihiciinus n superfam 27 27 27 gen n n fam Suborder Glyptocrinina Superfamily Melocrinitacea Family Paramelocrinidae Genus Dynamocriniis n gen 29 Superfamily Eucalyptocrinitacea Family Eucalyptocrinitidae Genus Aclisrocrimis n gen 31 Superfamily Patelliocrinacea Family Patelliocrinidae Genus Macrostylochnus 33 Superfamily Stipatocrinacea Family Stipalocrinidae Genus Slipatocriniis Order unknown 34 34 Subclass Disparida Superfamily Calceocrinacea Family Calceocrinidae Genus Thaerocriniis gen n 36 Superfamily Myelodactylacea Family Myelodactylidae Genus Eomyelodactyhis Genus Myeladacrytus 38 39 Family Tornatilicrinidae Genus Hapmcriiuis n gen 42 Bulletin 360 Subclass Cladida Order Cyathocrinina Superfamily Cyathocrinitacea Family Euspirocrinidae 45 Genus Euspiiocrinus Order Dendrocrinina Superfamily Dendrocrinacea Family Dendrocrinidae 48 Genus Dendrocrimis Subclass Flexibilia Order Taxocrinida Superfamily Taxocrinacea Family Taxocrinidae Genus Protaxocrinus 51 Order Sagenocrinida Superfamily Icthyocrinacea Family Icthyocrinidae Genus Prolixocriniis n gen • 53 Superfamily Sagenocrinitacea n fam n gen 56 56 ?Anisocrinid uncertain 58 Family Anisocrinidae Genus Kyphnsocrinus Family Sagenocrinitidae Genus Scapanocrinus Family unknown Subclass unknown n 61 gen 63 References Cited 64 65 66 Plates 71 Index 83 Holdfasts, columnals, and columns Appendix: Locality Register LIST OF ILLUSTRATIONS page Text-figure "Crinoidea of the Clinton Group", refigured from Hall Map Lithostratigraphic and chronostratigraphic relationships of Callistocrinus tesselatus n gen and sp plate diagram of holotype expanded plate diagram n sp plate diagrams Compsocrinus relictus n sp., plate diagram of holotype Atalocrinus arctus n gen and sp., plate diagrams Dynamocrinus robustus n gen and sp., plate diagrams Aclistocrinus capislratus n gen and sp., plate diagram Slipatocrinus hulveri Eckert and Brett, 1987, expanded plate diagram Tbaerocrinus crenatus n gen and sp., plate diagrams Eomyelodactylus columnal diagrams Myelodactylus linae n sp., diagram of holotype Haplocrinus ccdvatus n gen and sp., diagrams Haplocrinus sp., plate diagram Euspirocrinus wolcottense n sp., diagrams of growth series Dendrocrinus ursae n sp., diagrams of cup and column Dendrocrinus aphclos n sp., plate diagram Dendrocrinus haclronodosus n sp., diagram of crown Protaxocrinus anellus n sp., plate diagrams Flexible crinoid plate diagrams Kyphosocrinus tetreaulli n gen and sp., plate diagrams Kyphosocrinus tetreaulli n gen and sp., diagrams of interray variation 10 1 12 13 14 15 16 17 18 19 20 21 22 23 24 25 ( 1852) of study area indicating localities where crinoids were collected Tormosocrinus furberi Tormosocrinus furberi and gen and n gen, sp., ?Anisocrinid uncertain, plate diagram 26 Scapanocrinus nniricatus n gen and sp., plate diagrams Lower Silurian strata of western New York 10 21 23 24 26 28 30 32 35 37 38 40 43 45 46 49 50 51 53 55 56 59 61 62 Early Silurian Crinoids from New York: Eckert and Brett LIST OF TABLES Table Measurements of five specimens of Tormosocrinus furberi n gen and sp Measurements of holotype of Aclistochnus capistratus n gen and sp Measurments of three specimens of Thaerocriniis crenatus n gen and sp Measurements of five specimens of Haplocrinus calvatus n gen and sp Measurements of five specimens of Euspirocriniis wolcouense n sp Measurements of two specimens of Dendrocriniis uphelos n sp Measurements of three specimens of Prolaxocrimis anellus n sp Measurements of three specimens of Pmlixocrinus nodocaudis n gen and sp Measurements of six specimens of Kyph/i.socriini.K letreaidti n gen and sp page 25 32 37 44 46 51 57 58 60 EARLY SILURIAN (LLANDOVERY) CRINOIDS FROM THE LOWER CLINTON GROUP, WESTERN NEW YORK STATE James D Eckert P.O Box 168 Cobalt, Ontario POJ ICO CANADA AND Carlton E Brett Department of Geology University of Cincinnati Cincinnati, Ohio 45221-0013, U S ABSTRACT 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 (Aeronian) contains the following new genera: Dynamocrinus Thaerocrinus, Haptocrinus and Prolixocrinus; new species include Dynamochnus Two species of dis- robustus Thaerocrinus crenatus Haptocrinus calvatus, Prolixocrinus nodocaudis and Macrostylocrinus sp sparwus Eckert and £ unifonnis Eckert, and one unusual camerate Stipalocrinus 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, Alalocrinus Aclistocrinus Kyphosocrinus and Scapanocrinus all new genera; and the species Callistocrinus tesselatus Tormosocrinus furberi, Alalocrinus arclus Aclistocrinus capistralus Kyphosocrinus tetreaulti, Scapanocrinus inuricalus, Myelodactylus linae Euspirocrinus wolcottense, Dendrocrinus aphelos D bactronodosus, Haptocrinus sp., ?anisocrinid sp., and an unidentified flexible crinoid Protaxocrinus anellus n sp and five unidentified columnal types occur in the upper parid Eomxelodacnius E Telychian Willowvale Shale Taxonomic revisions also necessitate reassignments of three previously described taxa The disparid Macnanuiratylus Bolton is synonymized with Eomyelodactylus the flexible crinoid CUdochirus americanus Springer is reassigned to Prolixocrinus n Quinquecaudcx Brower and Veinus 1981, is synonymized with Dendrocrinus The is reviewed; the cotype specimens in part represent the cirral column of a myeassigned to Eoniyelodatyhis {E ' plumosus (Hall)); the remaining material consists gen and the cladid genus erroneous species Glyptocrinus plumosus Hall lodactylid disparid crinoid here tentatively of coiumnals and pluricolumnals probably belonging to Haptocrinus Physically stressed, uncrowded environments of the Early Silurian in western crinoid assemblages and provided a refuge for relictual Ordovician taxa that New became York were characterized by low diversity extinct in the late Llandovery Diverse assemblages of crinoids dominated by Wenlock precursors inhabited mixed carbonate-siliciclastic regimes Early Silurian crinoids of the Clinton Group are highly endemic other taxa f.e.g., distal to shoals low provincialism of Bea-Yeh Lin Eckert discovered many good specimens and additional material was found by Denis Te- is at the treault Financial support for this study are grateful to R Sheldon Furber was provided by Grant EAR 9219807 (to CB), the Geological Society of America, and Roy and Enid Bea-Yeh Lin NSF Eckert INTRODUCTION publication We to the generally erty based on part of a Ph D dissertation University of Rochester by the senior author This monograph benefited from critical reviews by William Ausich, Judy Massare, George C Mcintosh, and Curt Teichert We also thank Warren Allmon for his assistance in preparation of this manuscript for This study marked contrast brachiopods) during this interval ACKNOWLEDGMENTS completed in who kindly permitted Eckert to collect and excavate on his prop- The Early Silurian was a critical interval in the evo- lutionary history of the marine biosphere during which Early Sill'rian Crinoids from New York: Eckert and Brett ^ ô B A, y^i^p^- m Text-figure numbers and '^f — "Crinoidea modem H of the Clinton Group", refigured from Hall (1852 pi A 41) with original descriptions Original plate figure interpretation of figures indicated by square brackets Glyptocriniis plumosus A [3c] A fragment of the column, probably of the same species [partial column of Hupiocrinus n gen.] B [3e] The end of the same column enlarged C [3f] A fragment of the rock, with the surface nearly covered with the joints [columnals] of this crinoid D [3d] A few joints of the same enlarged, showing the longitudinal line of separation between the five parts of the plate [Haplocrinus pluricolun.nal illustrating pentamere suture] E [3g] Several of these joints enlarged, showing their variable character G [3b] Two joints of the finger enlarged, with several of the tentacular joints attached [detail oi Eomxieddactyhis cirri] H [4] Glyprocriinis sp [columnal of portion of a single finger, with the tentacula attached, [supposed crinoid arm, actually a partial unknown crinoid] column of Eomyeludactylus (herein I [3a] A tentatively designated Eomyelodacryhis"! plimiosiis (Hall)), figured upside down] Ichlhydcriims ? cUnumensis E [5] Partial arms of a flexible crinoid, possibly Prolixocrinus n gen Undetermined species J [6u] The specimen of the pinnulute arms of an undetermined camerate crinoid; natural size New major restructuring of ecosystems occurred following Group of Late Or(iovician extinctions (Sheehan 1982; (1852) figured fragmentary remains from these strata Brenchley, 1989; Boucot, 1990) Crinoids rebounded situation and erected two new species, Glyptocriniis plumosus and Icthyocrinus? clintonensis both from the Reynales Limestone (Text-fig ) Glyptocrinus plumosus is a composite of two disparid genera, consisting of a partial cirri-bearing column of Eomyelodactylus and columnals and an incomplete column probably belonging to Haptocrimis ccilvatus n gen and sp G plumosus is herein tentatively reasigned to Eomyelodactylus on the basis of the cirriferous column Ichthyocruius? clintonensis is represented by arms of an indetermin- described able flexible crinoid from this crisis 1975, and underwent a dramatic evolutionary radiation in the Early Silurian; subsequently, they be- came conspicuous and important elements of Wenlock marine communities (Frest et 1999) Early Silurian crinoids have traditionally been represented by a con- spicuous paleontologic gap that has inhibited investigations of the origin and paleoecology of their diverse Late Silurian descendants In less than a decade, this changed dramatically Early Silurian material from the Hopkinton Dolomite of Iowa (Witzke and Strimple, 1981), Power Glen Formation of New York (Brett, 1978) and Ontario (Eckert, 1984), Brassfield Formation of Ohio (Ausich, 1984a, b; 1985, 1986a, c, d; 1987, Ausich and Dravage 1988), and the lower Clinton Group of New York (this study) comprise about 70 crinoid genera represented by at least 100 species This stands species of crinoids, many in stark contrast to only 15 of them poorly known, listed from the Lower Silurian of North America by Bassler and Moodey (1943) Subsequently, Donovan et al (1992) and Donovan (1993) have also described six new Llandovery crinoids from the British Isles Previous work on crinoids of the lower Clinton York has been extremely limited Hall Gillette (1947), in his detailed lithostratigraphic faunal study of the Clinton Group of New York, and listed Dimerocrimis brachiatiis Hall from the Reynales Limestone at Mink Creek, near Williamson, and Dendrocrimis loiigidactylus Hall from the Lower Sodus Shale in a tributary of Sterling Creek near Martville Unfortunately, these specimens were not described or figured and their whereabouts are now unknown However, it is very probable that they were misidentified Dimerocrinites (Dimerocrimis) brachiatus is the Upper Silurian Rochester Shale; known only from Gillette's material was probably Stipatocrinus hulveri, described by Eckert and Brett (1987) from the Rey- Bulletin 360 nales Limestone at Rochester, niis longidactyliis Hall is New York Deudrocri- known only from the Roch- Thus, in an interval spanning nearly 150 years since on Silurian faucrinoid species has been the pioneering studies of Hall (1852) New York, not a single Lower Silurian portion of the Wenlock age Rochester formally described from the the Clinton Group Yet, Shale overlying these strata has yielded at least 28 cri- nozoan and blastozoan genera represented by more than 30 species The primary explanation as to why lower Clinton echinoderms have remained poorly known for so long is simply that these strata have never been carefully investigated for echinoderm remains Instead, attention has been focused on the Rochester Shale, justly fa- mous for and lor its abundant, well preserved fossils (see Tay- Brett, 1996) was obtained Most of the present study material New York (Text-fig east of Rochester, Here, the Clinton outcrop belt occurs in relatively 2) mantled by glacial detend to be small, patchy, and easily overlooked or discounted (PI 11, figs 1-4) In addition, except for hematites, formerly flat-lying terrrain extensively exposures Consequently, posits excavated for paint oxides in now defunct, small-scale mines, the lower portion of the Clinton Group has had economic value little It lacks thick carbonate sequenc- es suitable for aggregate and manufacture of concrete, such as those that have been quarried in the Brassfield Limestone and Hopkinton Dolomite Therefore, except few roadcuts and railroad embankments, for a artifical exposures of the lower Clinton Group are also limited These whose factors, together with the served echinoderms to occur in horizons, explains echinoderms in why tendency of well pre- thin, easily overlooked investigation of Early Silurian New York has been sporadic and des- IN NEW YORK Only a brief summary of the stratigraphy of the Clinton Group Gillette is presented here; for detailed review (1940, 1947), Kilgour (1963), Hunter summary is derived its not thoroughly un- thickest succession in New central York, the Clinton Group consists of dominantly sili- Appalachian Basin To the west, these strata grade into a thinner sequence of shelf carbonates interrupted by unconformities (Brett et al, 1990, 1998) Group Gillette (1947) subdivided the Clinton into lower, middle, and upper intervals Stratigraphy of the lower part of the Clinton Group was subsequently revised by LoDuca and Brett (1994) In western New York, the lower and middle Clinton are respectively represented by the Neahga-Maplewood Formation through Wolcott Furnace Iron Ore interval, and the Sauquoit Shale (LoDuca and Brett, 1994; Text-fig 3) These have been interpreted as third order depositional sequences S-II and S-III by Brett et al (1990, 1998) In western New York, the upper Clinton is represented by the Williamson Shale, Rockway Formation, Irondequoit Limestone, and Rochester Shale (Brett et al., 1990, 1995); in central New York it consists of the Westmoreland Iron Ore, Willowvale Shale, Dawes Formation, Kirkland Iron Ore, and Herkimer Sandstone interval The upper Clinton strata above the Williamson Shale and laterally equivalent Willowvale Shale, is Wenlock in age and is not considered further here LoDuca and Brett (1994) revised the stratigraphy of the lower portion of the Clinton Group The Clinton unconformably overlies the upper Medina Group (Thorold and Kodak sandstones) The basal contact of the Clinton Group, a sequence bounding unconformity, is marked by a thin (1-20 cm), but widespread phosphatic pebble bed, the Densmore Creek phosphate bed, ern STRATIGRAPHY OF THE CLINTON GROUP In still ciclastic rocks deposited in the eastern fringe of the at the ultory see interrelationships are derstood ester Shale nas of created a complex sequence of lithostratigraphic units base of the Maplewood-Neahga shales New York (Brett et al., 1990, 1995; in west- LoDuca and Brett, 1994) The unconformable contact is locally succeeded by the Neahga Shale in extreme western New York (Niagara County) and by equivalent Maplewood Shale in the Rochester area (Monroe County) The Neahga m (7 feet) of greenish-gray, (1970), and Muskatt (1972) This Shale consists of up to 2.2 from poorly fossiliferous, Eocoelia-hcarmg shale At Roch- Brett stratigraphic revisions of Lin and Brett (1988), et al (1990, 1995), and LoDuca and Brett ester, the Maplewood Shale consists of 6.5 m (21 feet) dominantly barren shale Samuel J Ciurca of Rochester (pers comm., 1988) collected (1994) The Clinton Group, named for exposures in the vicinity of Clinton, New York (Vanuxem, 1842), consists of approximately 30-107 m (100-350 feet) of of green, varied siliciclastic and carbonate strata that have been orthoconic nautiloids from this unit Both the Neahga subdivided into about sixteen formations Sea level os- and Maplewood shales represent quiet water condi- coupled with isostatically induced, progressive eastward migration of the Appalachian Basin axis (Goodman and Brett, 1994) tions cillation in the Early Silurian, fissile, small, undescribed camerate crinoids associated with in localized embayments Rochester, near Webster, thins abruptly and its New position or lagoons East of York, the is Maplewood taken by a thin (20- Bulletins of American Paleontology, Bulletin 360 Plate Early Silurian Crinoids from New York: Eckert and Brett 79 Explanation of Plate Page Figure I, 7, 10 12-14, 16-18 Scapanocriniis muricalus 1, 16 new genus and species Wolcott Limestone 62 Anterior view of nearly complete individual attached to fenestellid bryozoans Base of crown and column are pushed together, concealing basal and infrabasal circlets, x 1; Detail of holdfast X 1.9: 16 Detail of crown Note large numbers of interbrachials incorporated into cup and angularsided proximal free brachials Heterotomous arms are strongly endotomous X2 Holotype BMS 10 12, 1,3 E26386 10 Oblique view of cup Crushed CD interray is at right Hexagonal CD interray basal and anal X divide radial circlet Upper and lower arrows indicate C ray radial and radianal, respectively Note nearly cylindrical infrabasal B ray Arrow circlet, X1.7; 12 Opposite side of crown centered on indicates radianal, XI 5; 13 Cup centered on DE interray damaged X1.5 Paratype BMS E26385 17, 14 Incomplete crown 18 17 Detail circlet is indicated 2-5, 8, Paratype BMS 26389 by arrow XL Paratype BMS E26387 new genus and species Wolcott Limestone Crown centered on B ray, X2; D ray view, X2; Kyphosocrinus XL of intertertibrachials, x2; 18, Large, incomplete crown and proximal column Infrabasal 57 telreaiilti CD interray view X2 Paratype BMS 26383 5, in adoral view X2 Paratype BMS E26384 Aboral view of crown X2.5; CD interray X2 Paratype Crown 5, Damaged crown and a single row of preparation 11 15 BMS 26380 58 ?Anisocrinid species A Wolcott Limestone » partial column CD interray is at plates extending almost to top of Figured specimen BMS right Anal crown but llic X was originally succeeded by distal anitaxis was lost during E26390 Flexible crinoid species B Wolcott Limestone 11 Crown viewed from disarticulated base, X2; 15 Lateral view illustrating strongly heterotomous arms and cnckitomy y BMS E26391 63 Bulletin 360 80 Explanation of Plate Figure 1, 6, Page 1-13 Unknown 1, 11 crinoid species D Willowvale Shale 64 Proximal, medial, and distal sections, respectively, of nearly complete column Pentameric column pro.ximally pentagonal distally xl.2 BMS Articular surface of medial columnal with large 13 Articular surface of distal columnal, X2 new species round E2641Ia-c 12 2-5 7-9 Protaxocrinus anelliis is BMS lumen and di.stinct pentameres, X2 BMS E26412 E26413 Willowvale Shale 32 Anterior view of crown and long, incomplete column Distal columnals are barrel-shaped x2 Paratype BMS E26399 Anterior view of small crown Distal tips of arms were dissolved X2.5 Paratype in early diagnesis, BMS E26394b 4, Crown Paratype 7, 10 20 D centered on BMS Anal sac ray is represented by anal X and XI only, X2.5; B ray view X2.5 E26393 C ray view of crown that suffered complete dissolution of distal arms and most of column in early diagenesis Note narrow anitaxis attached to concave right shoulder of CD interray basal x3; Opposite side of crown A ray is at extreme left, X2.5 Holotype BMS E26392 Anterior view of crown Distal arms have been dissolved X2.5 Paratype Unknown 10 BMS E26394a 64 crinoid species C Wolcott Limestone BMS E26416 BMS E26417 Proximal column, x| 20 Distal column, XI 14-17 Tremichnus cysticus Brett Willowvale Shale 65 view of pluricolumnal engulfed by excess stereom covered with pits of T cysticus, X1.5; 15 Inferred distal end Excess stereom has tripled diameter of column, x2; 16 Inferred proximal end X2; 17 Lateral view of opposite side xl.5 Hypotype ROM 44359 14 Lateral 18 19, 25 Unknown crinoid species G Willowvale Shale Large, branched pscudocirrus 18 21 24 65 comprismg 19 Slightly curved pluricolumnal probably of this species, 25 Two Unknown partial holdfasts Example at right is E26415 64 recumbent column Rootlets are represented by elevated attachment 24 Pluricolumnal with encrusting bryozoans Unknown encrusted by crinoid species E Willowvale Shale 21 Section of 22, 23 BMS E26414 Xl.2 BMS E26418 bryozoans, xl.5 BMS part of holdfast, XI crinoid species 22 Axial E Kirkland Iron XL BMS scars, XI BMS E26437 E26438 Ore 65 view of large columnal extensively abraded before obliterated x|.3; 23 Side view xl.3 BMS E26439 final burial Articular surface has been completely Bulletins of American Paleontology, Bulletin 360 Plate ?Vv' I »i 25 J Plate 10 Bulletins of American Paleontology, Bulletin 360 ^^;» vy.::.i-: *# \>.l ^M^- ''0 -^r:^'!': ':.^^:5:>:« "J :::^' y^/ -^l^iiS&Kp'^:/ Early Silurian Crinoids from New York: Eckert and Brett 81 Explanation of Plate 10 Page Figure 1-6 Fossil assemblages of lower Clinton 12-15 Group pygidium (lower Packstone bearing ramose bryozoans calymenid Crinoidal grainstone consisting almost entirely of columnals of Haptocriniis trilobite Reynales Formation near base of Hickory Corners Member, locality left), and corroded rugose coral (lower right) X2.2 n gen X3.8 Reynales Formation near top of Hickory Corners Member, locality Bryozoan assemblage dominated by Fenestella tenuis (example in upper right) and Striatopora ftexiiosa (narrow branch crossing photograph near bottom) A small, articulated specimen oi Atrypa is also visible x3.4 Lower Wolcott Limestone, locality Brachiopod wackestone containing disarticulated and fragmented valves of Pentamerus, xl Wolcott Limestone, locality Grainstone consisting of fragmented and abraded ramose bryozoans, crinoid columnals, and small brachiopods, X2 Upper Sodus Shale, locality Shale bedding plane covered with the brachiopod Eocoelia hemisphaerica, represented by internal molds of mostly disarticulated valves, X3 Upper Sodus Shale, locality Bulletin 360 82 Explanation of Plate Page Figure 1—4 Lower Clinton Group exposures Crinoidal grainstone beds near top of Hickory Corners Member, Reynales Formation, locality Thin-bedded wackestones of basal Hickory Corners Member overlying Neahga Shale (contact at top of lens cover), locality Exposure on bank of Bear Creek Sterling Station Iron Ore between arrrows is situated above Bear Creek Shale and below Lower Sodus Shale, locality Excavation in bank of Mudge Creek Tools rest on poorly exposed shales and limestones of the lower portion of the Wolcott I Limestone, localitv Bulletins of American Paleontology, Bulletin 360 Plate INDEX shown Note: Page numbers tor descriptions of genera and species are in bold type blastozoans 65 Abacocrinidae Jaekel 1918 27 Bolkrimis Witzke and Strimple 198 aboral nerve network 34 Bo/ATOcrm.s Mcintosh, 1988 80 borings (see 15 BrachiiKiimts Hall, abrasion (of skeletons) 12, 14, Acemaspis Aclistncrmus n A capistrauis Acrocrinidae 31, 32 gen n ^p Wachsmuth and Springer 11 15, 16,31,32,76 embedment pits, 33 33 Tremichniis) 858 38 10, 11-17 42 81 brachiopods Brassfield Limestone (Formation) 1 12 20, 22 36 .39 27 885 Aeronian Stage (see Llandovery B-C4) 10, 11 47 50, ,54 7, 48 Biiariicnmis Angelin 878 33 Alisocrinus A letnirmaUis Brower Allocriniis Alsopocriniis Tansey, Alton, 973 Wachsmuth and Springer, 889 Britain (British Isles) 29 Brewer Dock Member Bromide Formation Brownsport Formation 33 924 48 NY 10 Amonohexacrinus Shevchenko, Ampheristocriniis Hall, 879 967 18 27 A ?Anisocrinid species 12 59 45 79 fam 19 Anisocrininae Frest and Strimple 1978 19 56 56 Anisdiiinus Angelin 1878 19 56 anoxia 16 18 Anisocrinidae n Buffalo, 10 10 12, 13, 15 16 17 25 BumasUis ioxus 64 Cabot Head Shale 28 Calceocrinacea 62 34 Calceocrinidae 96 18 .36 45 1962 X\x Meek and Worthen, 1869 Meek and Worthen, 1868 10, 31 CaUiochnus d'Orbigny 1849 Callistocrinidae n fam Archcietax(>ciiniis\^evj\s 1981 52 Callislocrinus 12-17 articulation (of crinoid skeletons) 920 19 56 25, 34 Ashgillian Stage n 19 20, gen 12, C tesselalus n sp calymenid 5, Camerate crinoid species camerate crinoids superfam 27 27 Auilocrinus n gen 12, A arclus n sp Atraclocrinus Kirk, 5, 11, 15, 27, 28, 29, 948 27 76 47 Atiypci 10 14, 7, autotomy 50 44 BA-1 13 Australia 48, BA-2 BA-3 BA-4 B A-5 Biutrocrinites Schnur, 13, 14, 17 13 17 17 13 48 849 bathy metric gradients 12 Bear Creek, NY Bear Creek Shale Beech River Member 11 10 14 15 18 26 M 49, 66, 74, 82 41, 61 Canistrocrinus 6-8 12-18 19-34 36 39 74 76 Wachsmuth and Springer 18 Carboniferous 27, 34, Carpocrinacea deKoninck Cai-yacriiules Say, & Le Hon 1854 12 34 Centhocrimis Bather 33 899 22 channel-dwelling crinoids Characlocriniis Brett, 198 34 52.61 Chesterian Chicaaocnnus Weller, 900 31 34 Chirocriiuis Angelin 1878 Chiropinna Moore 34 962 Chondrites 14 10 chronostratigraphic units 7, cirri Cladida Moore and Laudon 1943 bivalves Blackriveran Stage 27 Catatdiuicnnus Brett, 1981 II 12-17 51.61 825 cladid (indeterminate) 14, 25 carbonate buffering cladid crinoids (cladids) 13, 885 34 41 42 45 47 52 19 bioturbation Caradocian 13 biostratinomy 19 34 biological species 10, 20-21, 76 A benthic assemblages (BA) biostratigraphy 16 56 Camerata Wachsmuth and Springer, 1885 fam 15 28 10 81 15 n 11, trilobite 22 n 14 20-2 Calpiocrinus Angelin, 1878 asterozoan Atalocrinidae 13, 31 Atactocrinus Weller, 1916 Atalocrinacea 18,34 34,36 Calceocrinus HaW 1852 31 Asaph(>ci-init.s Springer, 34 16, calcisiltites Witzke and Strimple 1981 A noditsus Witzke and Strimple 1981 /\/(7;
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