SMITHSONIAN MISCELLANEOUS COLLECTIONS VOLUME 152, NUMBER Cljarless © anb iilarp S^efiearcl) *^aux OTalcott Jf unb LOWER AND MIDDLE CAMBRIAN TRILOBITE FAUNAS FROM THE TACONIC SEQUENCE OF NEW YORK (With 14 Plates) By FRANCO RASETTI Johns Hopkins University, Baltimore, Maryland Honorary Research Associate, Smithsonian Institution (Publication 4710) CITY OF WASHINGTON PUBLISHED BY THE SMITHSONIAN INSTITUTION PRESS AUGUST 29, 1967 PORT CITY PRESS, INC BALTIMORE, MD., U S A CONTENTS Page Introduction and Acknowledgments Occurrence of the Fossils Index of Localities 14 Biostratigraphy 15 Lower Cambrian 15 Middle Cambrian 22 Systematic Descriptions Order AGNOSTIDA Family AGNOSTIDAE Family PERONOPSIDAE Family DIPLAGNOSTIDAE Family Undetermined Order EODISCIDA Family EODISCIDAE Family PAGETIIDAE Order OLENELLIDA Family OLENELLIDAE Order Undetermined CORYNEXOCHACEA CORYNEXOCHIDAE DOLICHOMETOPIDAE ZACANTHOIDIDAE DORYPYGIDAE Superfamily Family Family Family Family Family OGYGOPSIDAE Family ORYCTOCEPHALIDAE Family Undetermined Superfamily PARADOXIDACEA Family CENTROPLEURIDAE Superfamily PTYCHOPARIACEA Family CONOCORYPHIDAE Family MENOMONIIDAE Family Undetermined 26 26 31 35 37 40 40 59 68 68 73 74 74 76 80 82 87 87 88 90 90 92 92 94 96 References 108 Plates 112 CfjarlejJ 33 anb iltarp Vaux Wlakott ^es^earcl) jFunb LOWER AND MIDDLE CAMBRIAN TRILOBITE FAUNAS FROM THE TACONIC SEQUENCE OF NEW YORK By franco rL\SETTI Johtts Hopkins University, Baltimore, Maryland Honorary Research Associate, Smithsonian Institution (With 14 Plates) INTRODUCTION AND ACKNOWLEDGMENTS In a previous paper (Rasetti, 1966a) the writer described a new faunule of Early Cambrian age discovered in bedded limestone of the Taconic sequence in the East Chatham 75^-minute quadrangle, Columbia County, New York The faunule was exceptional in the large number of new genera and species of the trilobite family Eodiscidae, exceeding the total formerly known for all of North America This finding stimulated an intensive search for fossils in Cambrian outcrops in northern Columbia County, with highly gratifying results A greater variety of Early Cambrian faunules than previously known from the Taconic sequence was discovered, and Middle Cambrian trilobites belonging to two faunizones were collected, thereby proving the existence of Cambrian strata of that age, contrary to the general belief held by previous students of that area For the first time in the study of the Cambrian of the Taconic sequence, it was possible to obtain several faunules in certain stratigraphic order from a single section Study of the Middle Cambrian faunas allowed a very precise correlation of the strata with those of northern Europe and the western United States This paper and is essentially based on the results of stratigraphic studies northern Columbia County However, commore northerly parts of the Rensselaer and Washington Counties, are occa- fossil collecting in parisons with strata and fossils in the Taconic sequence, sionally in made, even though those areas were by far not as thoroughly SMITHSONIAN MISCEUANEOUS COLLECTIONS, VOL 152, NO SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL 52 explored by the writer The early work of Ford, Dale, and Walcott, and the more recent one of Lochman (1956) has given a fairly complete description of the Early Cambrian fauna of this area, even though the existence of Early Cambrian faunules not referable to the Elliptocephala asaphoides assemblage had not been recognized (Theokritoff, 1964; Rasetti and Theokritoff, 1967) A paper on the stratigraphy of the Cambrian of Columbia County, describing in detail the sections which supplied the fossils discussed herein, will be published by Bird and Rasetti (in press) The present work was supported by two grants (nos 3454 and 4028) from the Penrose Fund of the American Philosophical Society, and the writer gratefully acknowledges his indebtedness to the Society Thanks are also due to several persons who gave valuable help in the course of the field work Dr John M Bird, responsible for the first finding of new Early Cambrian trilobites in Columbia County, continued to cooperate enthusiastically in the discovery and search of new fossiliferous localities and study of the stratigraphy, and accompanied the writer in a number of field excursions Dr Donald W Fisher contributed his knowledge of the area and suggested the examination of several potentially fossiliferous exposures, some of which were productive Dr A R Palmer accompanied the writer on a field excursion and collected valuable fossils Dr George Theokritoff also contributed to collecting, and accompanied the writer on an excursion in northern Washington County where he had thoroughly studied and mapped the rocks of the Taconic sequence To all these persons, and to Dr E-An Zen, the writer is also indebted for discussions on the stratigraphy and faunas OCCURRENCE OF THE FOSSILS General statement —The trilobites described herein, with a few exceptions of specimens from other areas illustrated for comparison, were collected by the writer, aided by the persons mentioned in the acknowledgments, in a limited portion of Columbia County, New York, chiefly either in the East Chatham 75^-minute quadrangle (Kinderhook 15-minute quadrangle) or the Hudson North 7>2minute quadrangle (Coxsackie 15-minute quadrangle) Almost all the material, excepting a few Lower Cambrian trilobites of the Elliptocephala asaphoides assemblage from shale deposits at Judson Point, was recovered from more or specimens are seldom flattened less pure limestone beds or from conglomerate boulders) The or distorted, and in general preserve lenses (only in exceptional cases —RASETTI SEQUENCE TRILOBITES, TACONIC NO the test and exhibit the aspect of the outer surface Further details the manner of preservation are mentioned on in the discussion of the various locaHties Most of the fossils were collected from outcrops, usually in meas- ured sections, hence in several cases the relative stratigraphic position of various faunules could be established Some of the specimens which were recovered from loose limestone blocks belong to faunules that are also known from bedded illustrated herein, in stone walls, rocks Localities, as in the previous paper (Rasetti, 1966a) are designated by the letters cs, followed by a locality number topographic position of each locality, the U S Geological Survey maps, tion is from a is A list indicating the determined by coordinates on given hereafter When a collec- loose block in a stone wall on or near the Griswold farm (the only area where collections from loose blocks were made), it is by the locality number (which may be that of a nearby outcrop, if any), and the letter L or M, to indicate a Lower or Middle Cambrian boulder, respectively, followed by a boulder number labeled by the letters cs followed An asterisk preceding the name in fossil lists indicates the type locality for the species For brevity, author's names are not indicated, since all the listed species are described either in the present paper or the previous one (Rasetti, 1966a) When the collection is sufficiently large, an indication of the frequency of species is given by the symbols (rr), very rare, (r), rare, and (c), common These indications are purely relative; e.g., a species indicated as common may be very rare in an absolute sense, only less so than another designated as rare in the same collection East Chatham quadrangle : Gristvold farm a hill —The area is located on about one mile SE of North Chatham, Columbia County, on the it supplied a great number of Lower and Middle Cambrian faunules, property of Mr Grafton Griswold, and trilobites, belonging to several both from outcrops and loose blocks This Cambrian A fossils were first is the area where unusual discovered in Columbia County in 1963 new Lower Cambrian faunule, number of eodiscid chiefly characterized by an excep- was already described (Rasetti, 1966a) from one bed exposed on the Griswold farm (collection cs-4), and conjectures were advanced concerning the relationship of the fossil bed to nearby outcrops After that paper was written, a trench deep enough to expose bedrock was excavated eastward from tionally large trilobites, SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL 52 the fossil locality, revealing a sequence of black shales with several some of which did not appear on show a uniform dip of 55° E and unquesrepresent a sedimentary sequence The trench was not interstratified limestone intervals, the surface All the strata tionably extended further in either direction, since surface exposures indicate that only green and black shales would have been encountered west- ward and eastward, respectively, for considerable distances ( road cut) indicates that the strata are not inverted; i.e., are exposed eastward A lens of Fossil Maiden Bridge evidence obtained by comparison with another section higher beds intraformational limestone conglom- exposed 20 feet stratigraphically below the The coarsely granular, light-gray matrix holds good specimens of Salter ella, but no other, more diagnostic, erate in green shale is lowest limestone listed below fossils could The be obtained trilobites collected from the limestone beds exposed in the trench are the following Collection cs-5 (USGS 4215), 58 feet above base: coll OlenelHd fragments Pagetides elegans Pagetides rupestris Peronopsis, sp undet Prosacanthoides, sp undet Collection cs-4c, 55 feet above base: Pagetides elegans Pagetides rupestris Collection cs-4b, 53 feet above base: Pagetides amplifrons Pagetides elegans Pagetides minutus Prosacanthoides, sp undet Collection cs-4a, 40 feet above base Bonnia, sp undet Neopagetina taconica OlenelHd fragments Pagetides minutus Peronopsis, sp undet Ptychopariacea, cranidium no Collection cs-4 at base (USGS coll 4216; Acimetopus bilobatus bed): * Acidiscus birdi * Acidiscus hexacanthus * Acimetopus bilobatus * Analox bipnnctata * Bathydiscus dolichometopus c r c c r TRILOBITES, TACONIC NO SEQUENCE —RASETTI * Bolboparia superba r * Bolboparia elongata r Bonnia, sp no r Bonnia, sp no r Bonnia, sp no r Bonnia, sp no r * Calodisais fissifrons * Calodiscus r occipitalis rr * Calodiscus reticulatiis r Eodiscidae, pygidium no rr Eodiscidae, pygidium no rr Kootenia, rr sp undet * Leptochilodiscus punctulatus * * r Litometopus longispinus r Olcnellus, sp no c Oodiscus binodosus rr * Oodiscus longifrons * r Paedeumias, c sp no Paedeumias, sp no * Serrodiscus griswoldi rr * Serrodiscus latus rr r * Serrodiscus spinulosus * Serrodiscus subclavatus r Serrodiscus, sp undet rr * Stigmadiscus gibbosus r * Stigmadiscus stenometopus r All the species (1966a) r Oodiscus subgranulatus from collection c cs-4 were described by Rasetti except Serrodiscus griswoldi, which is described herein, (p 52) Several other outcrops on the Griswold farm yielded a few fossils of the Pagetides fauna, showing approximate equivalence to collec- and cs-5 listed above In the wooded area just north of farm are several isolated outcrops, some of which produced a few, very fragmentary fossils Only one collection is worth tions cs-4b the Griswold listing Collection cs-15 Pagetia higranulosa Pagetides vtinutus An important exposure was found in the of the Griswold farm, S of a prmd not rangle many densely forested area marked on the USGS W quad- Limestone beds, partly fine-grained, partly granular with small pebbles and fossil fragments, form outcrops at this locality and produced an interesting Pagetides faunulc including two representatives of the family Eodiscidae SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL 52 Collection cs-29 Bonnia, sp undet r Eodiscidae, cephalon no rr Leptochilodiscus punctulatus rr Pagetia bigramilosa c c Pagetia laevis Pagetides atnplifrons r Pagetides elegaiis c Pagetides mimitus Peronopsis, Numerous case sp blocks holding c rr undet Lower Cambrian fossils, in all but one (CS-15/L3) belonging to the Pagetides fauna, were collected from the stone walls on or north and west of the Griswold farm In cases outcrops of the same age were located in the immediate vicinity However, in several cases the loose blocks produced more numerous or better preserved examples of some of the trilobite species The species from those blocks that supplied illustrated specimens all are listed hereafter Collection cs-3/Ll Pagetides elegans Pagetides rupestris Corynexochacea, pygidium no Collection cs-3/L2 Acidiscus? sp undet *Atia!ox obtusa Bonnia, sp undet rr r r Olenellid fragments Oodiscus, c sp undet rr Pagetia bigramilosa c r Pagetides elegans Pagetides leiopygus r Pagetides minutus c r Pagetides rupestris Protypus, sp undet Prozacanthoides, rr sp undet r Eodiscidae, pygidium no rr Collection cs-3/L3: Analox obtusa r Pagetia bigramilosa c Pagetides elegans r Pagetides minutus c Pagetides rupestris r Collection cs-15/Ll Calodiscus, sp undet Conocoryphidae, cranidium no rr rr SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL 152 NO if^f/lnl ^/,' 15 20 1$:*^ 16 >^ 22 LOWER CAMBRIAN TRIUOBITES 4, PLATE SMITHSONIAN MISCELLANEOUS COLLECTIONS 7^^ ''^% W' ^ Mm^£s triliiicaliis (coll USXM X5 (coll cs-15/1.2) W'hittington, from 21, 156645 94 cs-15/I.l ), USX.M 156681 97 I'.mmons Ruiiber imi)ressioM of cranidium flattened in shale, type species 156644 and dorsal views of cephalon Fig 22 23 12, Pacdcutnias, species no 19, 20, I>(jntal I'ig 156639 Pacdciiiiiias, species no Incomplete cephalon Figs 68 USXM Pacdciiiiiias, species no Incomplete cephala, X7.5 Fig 18 no Two X7.5 1, cs-15/L3), Pacdciiiiiias, species 10 same locality as coll cs-24b), X3 MCZ (coll H H 8536, i)lesio- Plate Page Free cheek, 1, 96 Riiiwuskia typica Resser Figs 1-3 X5 USNM cs-19) Cranidiuni, 2, 3, Cranidium, new 35 Xl8, 15-17, Pygidia, Xl8 types (all coll 156567, holotype Cephalon, 22, Xl2 13, 36 14, Cephala, USNM 156568, Xl8 para- cs-21) Goniagnostus, species undetermined Figs 18, 19 18, Glabella, USNM XlO- 29 19, Anterior portion of cephalon, XlO (coll cs-22) 156555 Grandagiwstus.', species undetermined Figs 20, 21 Dorsal and lateral views of cephalon, Xl2 27 (coll cs-23), USNM 156569 Hypagiwsfiis parznjrons (Linnarsson) 34 Xl8 (coll cs-22), USNM 156561, plesiotype 24, Xl2 (coll cs-23), USNM 156562, plesiotype 25, Cepha- Cephalon, Cephalon, lon, Xl8 (coll cs-21) USNM 156563, plesiotype Pcronopsis species no Cephalon, Fig 27 Pygidium, Xl2 9, Pygidium, 8, lateral USNM 12, Cephalon, Fig 26 156565, holo- USNM X18 Figs 12-17, 22 23, USNM views of pygidium, Xl2 156566 paratypes (all coll cs-22) Baltagnosfus sfockportciisis new species and 11, Dorsal Figs 23-25 (coll species Dorsal and lateral views of cephalon, Xl8, type 4, Cephalon, Xl2 5, Cephalon, Xl8 6, 7, 10, X4 156684, plesiotypes Baltagtwstiis angnsiilobns, Figs 4-11 X5 Xl8 (coll cs-21), ZZ USNM 156559 Hypagnostus, species undetermined Cephalon, Figs 28-30 Xl8 (coll cs-22), Ptycbagnostiis puiictiiosiis 28, Portion of cephalon, Smaller pygidium, Figs 31, 32 USNM XlO XlO 29, (coll cs-21 Lciopygcf, species no 35 156564 (Angclin) 28 Portion of pygidium, XlO ) USNM 30, 156551, plesiotypes 26 Lateral and dorsal views of cephalon, XlO (coll cs-21), USNM 156549 Fig 2i Lciopygcf species no Cephalon, XlO (coll cs-21), USNM 27 156550 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL 152 NO i^ Lower and Middlj: Cambrian TRiLOBiris 4, PLATE SMITHSONIAM MISCELLANEOUS COLLECTIONS • * I Jr At > I ^ * VOL 152 NO PLATE 10 4, J 'J kX-/'-^V\-i k-.-iai ii^.iJ^r •^^•^^?^ f if' 26 -! v^mOIM 32 -:f-' - .^'.'^y^: ^rm^ \ /t- JS^-i* '• ,:»* "^ 34 31 MIDDLE CAMBRIAN TRILOBITES , Pl.ATF 10 Page Figs 1-8 Ptycliac/Hostus tjihbus (Linnarsson x7-3 USXM 15(i35>l plcsio1, Cephaloii 5, 6, Pygidia (coll cs-7/Ml) types 2, 3, Cephala 4, Pygidium 7, 8, Dorsal and lateral vicw-.-^ of pygidium (coll cs-9d 156552, plesiotypes Pi-ro)iof5^' 4, 16 ," :^Ơr^ V^^f^ r^ n^-'.- 19?^-/ 22 i.' r ^^•"' 29 26 28 :f^ f 27 25 ', '*^.,^ :> MiODUE Cambrian trilobites * SWIITHSOMIAN MISCELLANEOUS COLLECTIONS MIDDLE CAMBRIAN TRILOBITES VOL 152 NO 4, PLATE 12 Plate 12 Page Coryiicxochidcs.' Figs 1-17 1, cvt^ivisiis new 74 specie.-; USXM Cranidium X7.5 (coll cs.-21), dium Xl2 3, 4, Hypostomes, XlO 156651, holotype 2, Crani- 6, 7, 5, Cranidium, xy.i Meraspid cranidia, X-^4 8-10, More advanced meraspid cranidia, Xl8 11, 16, Meraspid pygidia X^^ 12, 17, Lateral and posterior views of protaspis X^^^ 13, Dorsal view of protaspis, X24 14, Dorsal 15, USXM and Kootcnia species no Figs 18-21 18, 19, Exfoliated pygidia, Pygidium preserving of protaspis, X-24 cs-21) (coll ^ 20, E.xfoliated cranidium, XlO X5 test, (coll cs-Od*) Corynexochacea, pygidium no Figs 22, 23 Pygidium, 22, views lateral 156652, paratypes X7 - Pyj^ndiuni 23, USXM X5 • • 82 21, 156666 88 XlO (coll USXM cs-2n 156674 Figs 24-28 Modocia punctata, new 24-26, 28, 27, USXM 99 species (coll cs-21), USXM glabella 156688, XlO paratypes (coll cs-21), 156687 holotype Bathyurisctis, species undetermined cs-9d*) USXM Fragmentary cranidium X4 X4 31, Pygidium, X7.5 (coll cs-7/Ml) 156657 pygidium Fragmentary coll Xl2 Cranidium with partly exfoliated Figs 29-31 29, Cranidia, USXM 156658 30, 78 Plate 13 Page Figs 1-7 1, Pagctia crratica, new species, Xl2 61 USNM Cranidium (coll cs-7/M4) 156613, holotype 2, Cranidium (coll CS-7/M3,) 3, 4, Cranidia (coll cs-7/M4) 5, Pygidium (coll cs-7/M3) 6, Pygidium (coll cs-7/M4) 7, Pygidium (coll CS-7/M5) 156614, paratypes USXM Pagctia clytioidcs new species, Figs 8-16 8, 9, 12, 13, paratypes Cranidia 14, Xl2 10, 11, Pygidia Cranidium (coll 63 (coll cs-6) cs-9c), USNM USXM 156616, 156617, paratype (coll cs-6), USXM 17-19, Dorsal, lateral, and frontal views of cranidium, XlO, USX'M 15, 16, Dorsal and frontal views of cranidium 156615, holotype Figs 17-30 BolaspidcUa fisher i, new species 156682, holotype 20, 21, Free cheeks, XlO of meraspid cranidia, Xl8 dia, Xl2 USNM 29, 30, 94 22-28, Various stages More advanced meraspid 156693, paratypes (all coll cs-21) crani- SP^ITHSONIAN MISCELLANEOUS COLLECTIONS VOL 152 NO * ^ ^ q jf< -yr Mid V^ '-4] MIDDLE Cambrian trilobites 4, PLATE 13 -