Ammonites Middle Tithonian Barda Negra
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New and Poorly Known Perisphinctoidea (Ammonitina) from the Upper Tithonian of Le Chouet (Drôme, SE France)
Volumina Jurassica, 2014, Xii (1): 113–128 New and poorly known Perisphinctoidea (Ammonitina) from the Upper Tithonian of Le Chouet (Drôme, SE France) Luc G. BULOT1, Camille FRAU2, William A.P. WIMBLEDON3 Key words: Ammonoidea, Ataxioceratidae, Himalayitidae, Neocomitidae, Upper Tithonian, Le Chouet, South-East France. Abstract. The aim of this paper is to document the ammonite fauna of the upper part of the Late Tithonian collected at the key section of Le Chouet (Drôme, SE France). Emphasis is laid on new and poorly known Ataxioceratidae, Himalayitidae and Neocomitidae from the upper part of the Tithonian. Among the Ataxioceratidae, a new account on the taxonomy and relationship between Paraulacosphinctes Schindewolf and Moravisphinctes Tavera is presented. Regarding the Himalayitidae, the range and content of Micracanthoceras Spath is discussed and two new genera are introduced: Ardesciella gen. nov., for a group of Mediterranean ammonites that is homoeomorphic with the Andean genus Corongoceras Spath, and Pratumidiscus gen. nov. for a specimen that shows morphological similarities with the Boreal genera Riasanites Spath and Riasanella Mitta. Finally, the occurrence of Neocomitidae in the uppermost Tithonian is documented by the presence of the reputedly Berriasian genera Busnardoiceras Tavera and Pseudargentiniceras Spath. INTRODUCTION known Perisphinctoidea from the Upper Tithonian of this reference section. Additional data on the Himalayitidae in- The unique character of the ammonite fauna of Le Chouet cluding the description and discussion of Boughdiriella (near Les Près, Drôme, France) (Fig. 1) has already been chouetensis gen. nov. sp. nov. are to be published elsewhere outlined by Le Hégarat (1973), but, so far, only a handful of (Frau et al., 2014). -
Xenosphinctes N. Gen. (Ataxioceratidae, Lithacoceratinae), a New Rare Ammonite Genus from the Lower Tithonian (Hybonotum Zone) of SW Germany
VOLUMINA JURASSICA, 2017, XV: 155–160 DOI: 10.5604/01.3001.0010.7170 Xenosphinctes n. gen. (Ataxioceratidae, Lithacoceratinae), a new rare ammonite genus from the Lower Tithonian (Hybonotum Zone) of SW Germany Armin SCHERZINGER1, Günter SCHWEIGERT2 Key words: ammonites, Xenosphinctes berkai, Early Tithonian, biostratigraphy, Germany. Abstract. The new monotypic ammonite genus Xenosphinctes (type species: Xenosphinctes berkai n. sp.) is established. It is recorded from the Upper Jurassic, Early Tithonian, Hybonotum Zone, Riedense Subzone, eigeltingense α horizon from the Talmühle, N of Engen, Baden-Württemberg, SW Germany. INTRODUCTION AMMONITE FAUNA OF THE EIGELTINGENSE α HORIZON The Hangende-Bankkalke Formation is the youngest formation in the Upper Jurassic of Swabia. Its base is usual- The first comprehensive review of ammonites from the ly formed by an unconformity with a marked change in li- uppermost Jurassic in Swabia was provided by Berckhemer thology from coarse-grained bioclastic limestones or marl- & Hölder (1959). However, therein the focus was on the am- stones to pure mudstones (Schweigert, 1996). Its type monite fauna of the Late Kimmeridgian Beckeri Zone, and locality is an abandoned limestone quarry near the village of only very few taxa from higher levels have been reported. Eigeltingen, and its base is best exposed in a nearby section Ohmert & Zeiss (1980) started with a description of the am- along a railroad cut, NW of the Talmühle hamlet (Fig. 1). monite fauna of the Hangende-Bankkalke Formation in the The most abundant macrofossils in these basal parts of the western part of the Swabian Alb. On that occasion several formation are ammonites. Many of them are fragmented due important taxa from the basal part of this formation which to predation, but some of them are quite well-preserved as are typical of the former eigeltingense horizon were intro- steinkerns with superimposed sculpture of the outer shell. -
A Review of the Classification of Jurassic Aspidoceratid Ammonites – the Superfamily Aspidoceratoidea
VOLUMINA JURASSICA, 2020, XVIII (1): 47–52 DOI: 10.7306/VJ.18.4 A review of the classification of Jurassic aspidoceratid ammonites – the Superfamily Aspidoceratoidea Horacio PARENT1, Günter SCHWEIGERT2, Armin SCHERZINGER3 Key words: Superfamily Aspidoceratoidea, Aspidoceratidae, Epipeltoceratinae emended, Peltoceratidae, Gregoryceratinae nov. subfam. Abstract. The aspidoceratid ammonites have been traditionally included in the superfamily Perisphinctoidea. However, the basis of this is unclear for they bear unique combinations of characters unknown in typical perisphinctoids: (1) the distinct laevaptychus, (2) stout shells with high growth rate of the whorl section area, (3) prominent ornamentation with tubercles, spines and strong growth lines running in parallel over strong ribs, (4) lack of constrictions, (5) short to very short bodychamber, and (6) sexual dimorphism characterized by minia- turized microconchs and small-sized macroconchs besides the larger ones, including changes of sex during ontogeny in many cases. Considering the uniqueness of these characters we propose herein to raise the family Aspidoceratidae to the rank of a superfamily Aspi- doceratoidea, ranging from the earliest Late Callovian to the Early Berriasian Jacobi Zone. The new superfamily includes two families, Aspidoceratidae (Aspidoceratinae, Euaspidoceratinae, Epipeltoceratinae and Hybonoticeratinae), and Peltoceratidae (Peltoceratinae and Gregoryceratinae nov. subfam.). The highly differentiated features of the aspidoceratoids indicate that their life-histories -
301083243.Pdf
AMEGHINIANA ISSN 0002-7014 Revista de la Asociación Paleontológica Argentina Tomo XII Diciembre de 1975 N?4 THE INDO-PACIFIC AMMONITE MAY AITES IN THE OXFORDIAN OF THESOUTHERN ANDES By P. N. STIPANICIC', G. E. G. WESTERMANN 2 and A. C. RJCCARDI3 ABSTRACT: Oxfordian Iitho- and biostratigraphy of the Chilean and Argentine Andes is reviewed (P. N. Stipanicic). Within the Chacay Group, the Lower to basal Upper Oxfordian La Manga Formation, below, mostly detrital and biogenic, and the Upper Oxfordian Au- quilco Formation, above, mainly chemical, are distinguished. The La Manga Formation (with Gryphaea calceola lumachelle) is rich in ammonite faunas, particularly of thc upper Cordatum to lower Canaliculatum Zones. In Neuquén and Mendoza provinces of Argentina, the Pli- catilis Zone or Middle Oxfordian has yielded Perísphinctes spp., Euaspidoceras spp., Aspido- ceras spp., together with Mayaítes (Araucanites ) stípanícfcí, M. (A.) reyesi, and M. (A.) mulai, Westermann et Riccardi subgen. et spp. nov. The first find of Mayaitidae outside the Indo-Pacific province is discussed in light of _plate-tectonic theory. RESUMEN: La revisron Iito- y bioestratigráfica del Oxfordiano de los Andes de Argentina y Chile (P. N. Stipanicic) ha permitido reconocer dentro del Grupo Chacay: 1) abajo, la Formación La Manga, mayormente detrítica y biogénica, del Oxfordiano inferior-superior basa!, y 2) arriba, la Formación Auquilco, mayormente química, del Oxfordiano superior. La For- mación La Manga (con lumachelas de Gryphaea calceola) contiene abundante cantidad de amonitas, particularmente de las Zonas de Cordatum superior a Canaliculatum inferior. En las provincias de Mendoza y Neuquén,Argentina, la Zona de Plicatilis (Oxfordiano medio) contiene Perispbinctes spp., Euaspidoceras spp., Aspidoceras spp., conjuntamente con Mayaites (Araucanites) stipanicici, M. -
Kimmeridgian (Late Jurassic) Cold-Water Idoceratids (Ammonoidea) from Southern Coahuila, Northeastern Mexico, Associated with Boreal Bivalves and Belemnites
REVISTA MEXICANA DE CIENCIAS GEOLÓGICAS Kimmeridgian cold-water idoceratids associated with Boreal bivalvesv. 32, núm. and 1, 2015, belemnites p. 11-20 Kimmeridgian (Late Jurassic) cold-water idoceratids (Ammonoidea) from southern Coahuila, northeastern Mexico, associated with Boreal bivalves and belemnites Patrick Zell* and Wolfgang Stinnesbeck Institute for Earth Sciences, Heidelberg University, Im Neuenheimer Feld 234, 69120 Heidelberg, Germany. *[email protected] ABSTRACT et al., 2001; Chumakov et al., 2014) was followed by a cool period during the late Oxfordian-early Kimmeridgian (e.g., Jenkyns et al., Here we present two early Kimmeridgian faunal assemblages 2002; Weissert and Erba, 2004) and a long-term gradual warming composed of the ammonite Idoceras (Idoceras pinonense n. sp. and trend towards the Jurassic-Cretaceous boundary (e.g., Abbink et al., I. inflatum Burckhardt, 1906), Boreal belemnites Cylindroteuthis 2001; Lécuyer et al., 2003; Gröcke et al., 2003; Zakharov et al., 2014). cuspidata Sachs and Nalnjaeva, 1964 and Cylindroteuthis ex. gr. Palynological data suggest that the latest Jurassic was also marked by jacutica Sachs and Nalnjaeva, 1964, as well as the Boreal bivalve Buchia significant fluctuations in paleotemperature and climate (e.g., Abbink concentrica (J. de C. Sowerby, 1827). The assemblages were discovered et al., 2001). in inner- to outer shelf sediments of the lower La Casita Formation Upper Jurassic-Lower Cretaceous marine associations contain- at Puerto Piñones, southern Coahuila, and suggest that some taxa of ing both Tethyan and Boreal elements [e.g. ammonites, belemnites Idoceras inhabited cold-water environments. (Cylindroteuthis) and bivalves (Buchia)], were described from numer- ous localities of the Western Cordillera belt from Alaska to California Key words: La Casita Formation, Kimmeridgian, idoceratid ammonites, (e.g., Jeletzky, 1965), while Boreal (Buchia) and even southern high Boreal bivalves, Boreal belemnites. -
Upon the Systematics of the Mesozoic Ammonitida
bodoA0)30e?f% 80060060660)6 od6<$03f)0b 80V)8oO, 160,^1, 1999 BULLETIN OF THE GEORGIAN ACADEMY OF SCIENCES,' 160, J* 1, 1999 PALEONTOLOGY I.Kvantaliani, Corr. Member of the Academy M.Topchishvili, T.Lominadze, M.Sharikadze Upon the Systematics of the Mesozoic Ammonitida Presented January 25, 1999 ABSTRACT. Systematics of the ammonoids highest taxa is based on the septa! line onto-phylogcny and the indexing of septal line elements isfounded on the homol ogy. Basing on the septal line development alongside with already known suborders (Ammonitina, Pcrisphinctina (emend.), Haploccratina, Ancyloccratina) wc have stated two new suborders Olcostcphanina and Cardioccratina. Key words: systematics. homology. Ammonitida. Systematics and phytogeny of the highest taxa of the Jurassic-Cretaceous Ammonitida are described in a number of works f 1-9]. Analysis of (he ontogenesis of septal lines (and some other signs) allowed N.Bcsnosov and 1. Michailova |2.3| to establish four suborders within the order of Ammonitida - Ammonitina Hyatt. 1889: Haploceratina Bcsnosov ct Michailova. 1983: Ancyloccratina Wiedmann. 1966 and Pcrisphinctina Bcsnosov cl Michailova. 1983, A. new suborder of Pcrisphinctina J3J. identified by N. Bcsnosov and I. Michailova in 1983. and phylogenetically closely related to it systematics of taxons arc of special interest. In turn, the suborder of Pcrisphinctina comprises four supcrfamilics (33 families): Stephanoceratoidea Ncumayr. 1875: Pcrisphinctoidca Stcinmann. 1890: Desmoceratoidca Zittcl. 1895 and Hoplitoidca H. Douville, 1890 [3j. Within the super- family of Perisphinctoidea s. lato the family of Olcostephanidae Pavlov. 1892. was previ ously mentioned. Earlier, on the basis of morphogenctic study of shells of some represen tatives of various families of Pcrisphinctidac |4-6}. -
Remarks on the Tithonian–Berriasian Ammonite Biostratigraphy of West Central Argentina
Volumina Jurassica, 2015, Xiii (2): 23–52 DOI: 10.5604/17313708 .1185692 Remarks on the Tithonian–Berriasian ammonite biostratigraphy of west central Argentina Alberto C. RICCARDI 1 Key words: Tithonian–Berriasian, ammonites, west central Argentina, calpionellids, nannofossils, radiolarians, geochronology. Abstract. Status and correlation of Andean ammonite biozones are reviewed. Available calpionellid, nannofossil, and radiolarian data, as well as radioisotopic ages, are also considered, especially when directly related to ammonite zones. There is no attempt to deal with the definition of the Jurassic–Cretaceous limit. Correlation of the V. mendozanum Zone with the Semiforme Zone is ratified, but it is open to question if its lower part should be correlated with the upper part of the Darwini Zone. The Pseudolissoceras zitteli Zone is characterized by an assemblage also recorded from Mexico, Cuba and the Betic Ranges of Spain, indicative of the Semiforme–Fallauxi standard zones. The Aulacosphinctes proximus Zone, which is correlated with the Ponti Standard Zone, appears to be closely related to the overlying Wind hauseniceras internispinosum Zone, although its biostratigraphic status needs to be reconsidered. On the basis of ammonites, radiolarians and calpionellids the Windhauseniceras internispinosum Assemblage Zone is approximately equivalent to the Suarites bituberculatum Zone of Mexico, the Paralytohoplites caribbeanus Zone of Cuba and the Simplisphinctes/Microcanthum Zone of the Standard Zonation. The C. alternans Zone could be correlated with the uppermost Microcanthum and “Durangites” zones, although in west central Argentina it could be mostly restricted to levels equivalent to the “Durangites Zone”. The Substeueroceras koeneni Zone ranges into the Occitanica Zone, Subalpina and Privasensis subzones, the A. -
The Bajocian-Kimmeridgian Ammonite Fauna of the Dalichai Formation in the Se Binalud Mountains, Iran
Informes del Insitituto de Reports of the Instituto de Fisiografía y Geología Fisiografía y Geología Volumen 1 Volume 1 (2014) (2014) THE BAJOCIAN-KIMMERIDGIAN AMMONITE FAUNA OF THE DALICHAI FORMATION IN THE SE BINALUD MOUNTAINS, IRAN Horacio Parent, Rosario Ahmad Raoufian, Mashhad Kazem Seyed-Emami, Tehran Ali Reza Ashouri, Mashhad Mahmoud Reza Majidifard, Tehran Rosario, Septiembre 2014 Informes del Insitituto de Fisiografía y Geología, Volumen 1 (2014) - Bajocian-Kimmeridgian ammonites, Binalud Mountains (Iran) THE BAJOCIAN-KIMMERIDGIAN AMMONITE FAUNA OF THE DALICHAI FORMATION IN THE SE BINALUD MOUNTAINS, IRAN Horacio Parent, Ahmad Raoufian, Kazem Seyed-Emami, Ali Reza Ashouri, Mahmoud Reza Majidifard Horacio Parent La fauna de amonites del intervalo Bayociano-Kimmeridgiano (Jurásico Medio-Superior) de la Formación [[email protected]]: Dalichai en el sudeste de la Cordillera Binalud, Irán. Laboratorio de Paleontología, IFG, Facultad de Ingeniería, Universidad Resumen: La Cordillera Binalud en el al noroeste de Irán es considerada la extensión oriental de la Cordillera Nacional de Rosario, Pellegrini 250, Alborz. La sucesión jurásica y la fauna de amonites de tres secciones seleccionadas (Dahaneh-Heydari, Bojnow 2000 Rosario, Argentina. and Baghi) de la Formación Dalichai fueron muestreadas capa por capa con fines sedimentológicos y Ahmad Raoufian paleontológicos. La fauna de amonites es abundante y representa el intervalo Bayociano Superior-Oxfordiano [[email protected]] Superior en la sección Baghi, pero solamente Oxfordiano Superior-Kimmeridgiano Inferior en las secciones Department of Geology, Faculty Dahaneh-Heydari y Bojnow. of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran Palabras clave: Cordillera Binalud, Formación Dalichai, Bayociano-Kimmeridgiano, Baghi, Dahaneh- Heydari,. Bojnow. Kazem Seyed-Emami School of Mining Engineering, University College of Engineering, University of Tehran, P.O. -
Note on the Ammonite — Bearing Beds in the Various Localities of Turkey - Part One: Ankara Region
NOTE ON THE AMMONITE — BEARING BEDS IN THE VARIOUS LOCALITIES OF TURKEY - PART ONE: ANKARA REGION Mükerrem TÜRKÜNAL Mineral Research and Exploration Institute of Turkey INTRODUCTION While working on «The Mono- graphic Revision of the Ammonites Fa- una of Turkey» (to be published later), the author has prepared a note on the Ammonite-bearing beds of Turkey. In this note are assembled the data of the available literature on this subject with the listing of fossil names as given by the authors; the synonyms are given here only for a few well-known species. In the Monography, each of these fos- sils will be fully discussed and all the synonyms of the fossils will be given. In the present note, we are beginning with the beds of the Ankara region. The other localities will be the subject of the following notes. LOCALITY : ANKARA In this district, there are several beds known from the early works. The most important ones will be listed below. A - Balkuyumcu. — In 1887, Tchihatcheff (10) studied first this Jurassic outcrop and found concave-fractured limestone. This limestone contains : A. tortisulcatus (= Sowerbyceras tortisulcatum D'Orb.) A. ardennensis (= Peltoceratoides ardennensis D'Orb.) A. plicatilis (= Perisphenctes plicatilis Sow.) A. tatricus (= Phyllocefas tatricum (Pusch) ?) Age. — Oxfordian. 68 Mükerrem TÜRKÜNAL B - Kesiktaş. — Pompeckj (7), in 1897, made a detailed study of the Juras- sic of Ankara. In his book, he mentioned these fossils : Arietites cf. rotator Reynes A. cf. latesulcatus Quens. Aegoceras sp. aff. brevispinae Sow. Phylloceras alontinum frondosum Reynes Ph. hebertinum Reynes His fossil locality must be wrong. Because, according to several authors, no Jurassic series were encountered in the given locality. -
The Transversarium-Bifurcatus Zone Boundary at Rocha (Peral Area, East-Centralalgarve, Portugal)
The Transversarium-Bifurcatus Zone boundary at Rocha (Peral area, East-CentralAlgarve, Portugal) B.MARQUES * F. OLORIZ ** F. J. RODRIGUEZ-TOVAR ** P. S. CAETANO * * - Centro Estratigrafia e Paleobiologia da UNL, Faculdade de Ciencias e Tecnologia, Quinta da Torre, P-2825 Monte de Caparica, Portugal ** - Dpto. Estr. Paleont., Fac. Ciencias, Univ. Granada and Inst. And. Geol. Mediterranea (LA.G.M.) 18002 Granada, Spain pp. 109-125 Ciencias da Terra (UNL) Lisboa NQll 1992 3 figs., 2 pI. zones Bifurcatus/Bimammatum a ete reconnue une autre discontinuite, correspondanta celledu type II quisepareles RESUMO cycles 4.3-4.4 de HAQ et al. (1987); cette discontinuite avait deja ete individualisee sur la marge sud de I'Iberie. Palavras-chave: Amonites - Macroinvertebrados Dans I' intervalle entre la partie superieure de la zone bentonicas - Biostratigrafia - Ecostratigrafia a Transversarium et la partie inferieure de la zone a Descontinuidades-s--Jurdssico superior-Oxfordiano-:- Bimammatum,l'analysedel'evolutionecostratigraphique, Algarve- Sui de Portugal. faite a partir des spectres de la faune, a montre que dans I'ensemble des cephalopodes, les ammonites sont les Este trabalho representa 0 primeiro estudo organismesles plus tolerantsau stressecologique,provoque, pormenorizado do limite das Zonas de Transversarium soitparla diminution del'ecospace, soitpardes arrivees de Bifurcatus no Algarve. Este limite esta associado, na area materiel terrigene; dans ces conditions, la faune benthique do Peral, a uma descontinuidade estratigrafica cujo hiato diminue considerablernent. Dans l'ensemble de la faune afecta, parcialmente, as Zonas de Transversarium e de recoltce on signale la presence, relativement abondante et Bifurcatus. Uma outra descontinuidade foi reconhecida no diversifice, desDichotomoceras,auparavantpascommuns. limite das Zonas de Bifurcatus-Bimarnrnatum que, nesta area, coincide com a descontinuidade doTipo II que separa osciclos4.3-4.4 de HAQet al. -
Annual Meeting 2002
Newsletter 51 74 Newsletter 51 75 The Palaeontological Association 46th Annual Meeting 15th–18th December 2002 University of Cambridge ABSTRACTS Newsletter 51 76 ANNUAL MEETING ANNUAL MEETING Newsletter 51 77 Holocene reef structure and growth at Mavra Litharia, southern coast of Gulf of Corinth, Oral presentations Greece: a simple reef with a complex message Steve Kershaw and Li Guo Oral presentations will take place in the Physiology Lecture Theatre and, for the parallel sessions at 11:00–1:00, in the Tilley Lecture Theatre. Each presentation will run for a New perspectives in palaeoscolecidans maximum of 15 minutes, including questions. Those presentations marked with an asterisk Oliver Lehnert and Petr Kraft (*) are being considered for the President’s Award (best oral presentation by a member of the MONDAY 11:00—Non-marine Palaeontology A (parallel) Palaeontological Association under the age of thirty). Guts and Gizzard Stones, Unusual Preservation in Scottish Middle Devonian Fishes Timetable for oral presentations R.G. Davidson and N.H. Trewin *The use of ichnofossils as a tool for high-resolution palaeoenvironmental analysis in a MONDAY 9:00 lower Old Red Sandstone sequence (late Silurian Ringerike Group, Oslo Region, Norway) Neil Davies Affinity of the earliest bilaterian embryos The harvestman fossil record Xiping Dong and Philip Donoghue Jason A. Dunlop Calamari catastrophe A New Trigonotarbid Arachnid from the Early Devonian Windyfield Chert, Rhynie, Philip Wilby, John Hudson, Roy Clements and Neville Hollingworth Aberdeenshire, Scotland Tantalizing fragments of the earliest land plants Steve R. Fayers and Nigel H. Trewin Charles H. Wellman *Molecular preservation of upper Miocene fossil leaves from the Ardeche, France: Use of Morphometrics to Identify Character States implications for kerogen formation Norman MacLeod S. -
Redalyc.Upper Jurassic Ammonites and Bivalves from the Cucurpe
Revista Mexicana de Ciencias Geológicas ISSN: 1026-8774 [email protected] Universidad Nacional Autónoma de México México Villaseñor, Ana Bertha; González Léon, Carlos M.; Lawton, Timothy F.; Aberhan, Martin Upper Jurassic ammonites and bivalves from the Cucurpe Formation, Sonora (Mexico) Revista Mexicana de Ciencias Geológicas, vol. 22, núm. 1, 2005, pp. 65-87 Universidad Nacional Autónoma de México Querétaro, México Available in: http://www.redalyc.org/articulo.oa?id=57222107 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Revista Mexicana de Ciencias Geológicas,Upper v. 22, Jurassic núm. 1, ammonites 2005, p. 65-87 and bivalves from Sonora 65 Upper Jurassic ammonites and bivalves from the Cucurpe Formation, Sonora (Mexico) Ana Bertha Villaseñor1,*, Carlos M. González-León2, Timothy F. Lawton3, and Martin Aberhan4 1 Departamento de Paleontología, Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510 México, D. F., Mexico. 2 Estación Regional del Noroeste, Instituto de Geología, Universidad Nacional Autónoma de México, 83000 Hermosillo, Sonora, Mexico. 3 Department of Geological Sciences, New Mexico State University, Las Cruces, NM 88003, USA. 4 Museum für Naturkunde, Zentralinstitut der Humboldt-Universität zu Berlin, Institut für Paläontologie, Invalidenstr. 43, D-10115 Berlin, Germany. * [email protected] ABSTRACT Four new molluscan assemblages from north-central Sonora indicate that the Cucurpe Formation ranges in age from late Oxfordian to early Tithonian. These assemblages extend the known paleogeographic range of Late Jurassic Tethyan fossil groups several hundred km to the northwest and improve correlation of Upper Jurassic strata in northern Mexico.