Uppermost Devonian ammonoids from Oklahoma and their palaeobiogeographic significance
R. THOMAS BECKER1, ROYAL H. MAPES2
1Institut für Geologie und Paläontologie, Westfälische Wilhelms-Universität, D-48149Münster,
Corrensstr. 25, Germany.
rbecker@uni-muenster.de
2Department of Geological Sciences, Ohio University, Athens 45701, U.S.A.
mapes@ohio.edu.edu
ABSTRACT: The upper part of the Woodward Shale of southern Oklahoma has yielded the first moderately diverse
North American ammonoid fauna from the uppermost Famennian (Upper Devonian VI). It includes six species from three clymeniid and one goniatite
family: Kielcensia vagabunda sp. nov., Riphaeoclymenia polygona sp. nov., R. pontotocensis
sp. nov., Cyrtoclymenia cf. procera Czarnocki, 1989, Spirosporadoceras overi gen. nov. sp. nov., and
a poorly preserved different juvenile sporadoceratid that may represent a second new genus. For comparison,
the related Spirosporadoceras delicatum sp. nov. from Germany is described. Kielcensia specimens from Oklahoma
represent the first uncontested record of triangularly coiled wocklumeriids from North America. Together
with Riphaeoclymenia, the Oklahoma fauna has similarities and strong biogeographical ties with the far distant
Holy Cross Mountains of Poland. Kielcensia and Riphaeoclymenia are missing from the diverse contemporaneous
ammonoid faunas of Middle and Southern Europe, which were located between the Oklahoma and the
Polish occurrences. Geographically intermediate contemporaneous Moroccan faunas also show a fundamentally
different composition but the Afro-Appalachian migration route must have been viable in the uppermost Famennian
Migrations through regions without leaving a trace in available very rich fossil records (“ghost distributions”)
create a bias for the palaeobiogeographical analysis of nektonic organisms. The faunal composition
of the Woodford Shale suggests a control of ammonoid distribution patterns by palaeoecological factors that are
not recognizable in the lithofacies.
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Some peculiar rugose coral taxa from Upper Serpukhovian strata of the Czech Republic
JERZY FEDOROWSKI
Institute of Geology, Adam Mickiewicz University, Maków Polnych 16, PL-61-606 Poznan, Poland.
jerzy@amu.edu.pl
ABSTRACT: Two genera from Upper Serpukhovian strata in the Czech Republic part of the Silesian Coal Basin are described
and figured. Ostravaia gen. nov., included in Ostravaiainae subfam. nov., may belong to the Family Antiphyllidae
Ilina, 1970. It is represented by one, morphologically variable new species, O. silesiaca. Two other species,
conditionally included in that genus, are left in open nomenclature. Variaxon gen. nov., included in Variaxoninae
subfam nov. of an undetermined family, is represented by two species, one of which, V. radians, is new.
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Late Ladinian radiolarians from the Tahtalidag Nappe of the Antalya nappes, SW Turkey: remarks on the late Middle and Late Triassic
evolution of the Tahtalidag Nappe
UGUR KAGAN TEKIN1, ILHAN SÖNMEZ2
1Hacettepe University, Geological Engineering Department, 06800 Beytepe, Ankara, Turkey.
uktekin@hacettepe.edu.tr
2General Directorate of Mineral Research and Exploration, Depatment of Mineral Research and Exploration,06520 Balgat, Ankara, Turkey
ABSTRACT: The late Ladinian to Late Triassic succession of the Tahtalidag (upper) Nappe of the Antalya nappes was studied
in the Egregindere section, north of the city of Antalya, SW Turkey. The chert bands in the central part of
the section have yielded poorly to moderately preserved radiolarians documenting the Late Ladinian Muelleritortis
firma and Muelleritortis cochleata radiolarian zones. Based on the Egregindere succession, a major deepening
event, evidenced by radiolarian cherts, took place between the middle and late Late Ladinian. The Late
Triassic thick-bedded neritic limestones represent a shallowing-upward sequence, which formed as a result of
the horst-like rising of the Tahtalidag Nappe during the Late Triassic block faulting.
Fifty-nine radiolarian taxa have been determined from the Upper Ladinian of the Egregindere section. One
species (Muelleritortis elegans) and two subspecies (Muelleritortis firma equispinosa and Muelleritortis firma
globosa) are described as new.
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The myth of the Triassic lytoceratid ammonite
Trachyphyllites Arthaber, 1927, in reality an Early
Jurassic Analytoceras hermanni Gümbel, 1861
RENÉ HOFFMANN1, HELMUT KEUPP2
Freie Universität Berlin, Department of Earth Sciences, Institute of Geological Sciences, Branch Palaeontology,
Malteserstrasse 74-100, Building D, 12249 Berlin, Germany.
1
mind@zedat.fu-berlin.de,
2
keupp@zedat.fu-berlin.de
ABSTRACT: The ammonoid “Trachyphyllites costatum”Arthaber (1927), based on a single specimen from an erratic boulder
of presumed Late Triassic (Norian age) from Timor, (Indonesia), was originally described as a phylloceratid
but later recognized as a true lytoceratid by Basse (1952) and Schindewolf (1961), and used by Wiedmann (1966a,
1966b, 1970) to support his idea of a polyphyletic origin of the post-Triassic ammonoids and of the Late Triassic
roots of the lytoceratids. New collections of additional specimens and associated taxa from other erratic boulders
in the type locality have confirmed observations (Tozer 1971; Krystyn 1978) that the age of the original boulder
was misinterpreted, and have shown that “Trachyphyllites” is actually of Early Jurassic (Hettangian) age.
An unpublished generic revision of the entire superfamily Lytoceratoidea by Hoffmann (2009) has shown
that “Trachyphyllites costatum Arthaber” is a junior synonym of Analytoceras hermanni (Gümbel, 1861), a taxon
thought by Wähner (1894) to be a subjective synonym of Analytoceras articulatum (J. Sowerby, 1831) We reestablish
the species Analytoceras hermanni (Gümbel, 1861) for Analytoceras articulatum “Type B” (Wähner
1894), which is characterized by a wide umbilicus and a small whorl expansion rate. The morphologically distinct
“Type A” (Wähner 1894) corresponds to the type species of Analytoceras, A. articulatum (J. Sowerby, 1831).
A revised phylogeny of the Early Jurassic lytoceratids is presented.
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Occurrence and significance of Cenomanian belemnites in the lower Danubian Cretaceous Group (Bavaria, southern Germany)
MARKUS WILMSEN1 , BIRGIT NIEBUHR1 AND PATRICK CHELLOUCHE 2
1Senckenberg Naturhistorische Sammlungen Dresden, Museum für Mineralogie und Geologie, Sektion Paläozoologie, Königsbrücker Landstr. 159, D – 01109 Dresden, Germany.
markus.wilmsen@senckenberg.de
niebuhr.birgit@googlemail.com
2GeoZentrum Nordbayern, Fachgruppe PaläoUmwelt, Loewenichstr. 28, D – 91054 Erlangen, Germany.
patrick.chellouche@gzn.uni-erlangen.de
ABSTRACT: The belemnite records of the lower Danubian Cretaceous Group (DCG, northeastern Bavaria, southern Germany)
are compiled, taxonomically described and placed within the new integrated stratigraphic framework of
the group. Three specimens from the lower Regensburg Formation (Saal Member) south of Regensburg can be
assigned to Neohibolites cf. ultimus (d’Orbigny) and are dated as late Early Cenomanian (Mantelliceras dixoni
Zone). Eight specimens represent Praeactinocamax plenus (Blainville) and occur in an event (plenus Event) in
the lower Eibrunn Formation (Regensburg area) or basal Regensburg Formation (Roding area in the Bodenwöhrer
Senke). Biostratigraphy and carbon stable isotopes suggest that the belemnite horizon with P. plenus in
the DCG has strictly the same chronostratigraphic position (mid-Late Cenomanian, middle Metoicoceras geslinianum
Zone) as elsewhere in Central and NW Europe. The lithostratigraphic units of the lower Danubian
Cretaceous Group (i.e., the Regensburg and Eibrunn formations), however, are characterized by a pronounced
diachronism based on their time-transgressive (i.e., onlapping) deposition during the Cenomanian–Early Turonian
transgression. The distribution of P. plenus around the Mid-European Island can be easily explained by
migration around the positive area without the necessity of a marine strait across the Bohemian Massif.
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High resolution biostratigraphy based on planktic foraminifera across the Cretaceous–Paleogene transition at the Bidart section (SW France)
NJOUD GALLALA1 AND DALILA ZAGHBIB-TURKI2
Université de Tunis El Manar, Faculté des Sciences de Tunis, Département de Géologie, Unité de recherche GEODPS (UR: 02/UR/10-02), Campus universitaire, 2092 Tunis, Tunisia.
1gnoujoud@gmail.com
2dalila.zaghbib@fst.rnu.tn
ABSTRACT:Based on high resolution biostratigraphic analysis of planktic foraminifers, it is confirmed that the Bidart section
(eastern margin of the Atlantic Ocean) represents a continuous Cretaceous–Paleogene (K-Pg) succession.
Nevertheless, the foraminiferal species Plummerita hantkeninoides, regarded as a latest Maastrichtian marker
species, is absent and Abathomphalus mayaroensis ranges to the top of the Maastrichtian (= K/Pg boundary).
Pseudoguembelina hariaensis is present throughout the succession, and it is proposed herein to substitute Pl. hantkeninoides
as the marker of the uppermost Maastrichtian.
At least 53 out of 72 species became suddenly extinct at the K/Pg boundary, defined by the Ir anomaly (Bonté
et al. 1984; Delacotte et al. 1982). The extinct species are represented by globotruncanids and large heterohelicids,
characteristic of the tropical-subtropical deep photic sea water under the mesotrophic conditions of the Late
Maastrichtian. The Lower Danian succession (the zones of Guembelitria cretacea, Parvularugoglobigerina eugubina,
Parasubbotina pseudobulloides) is less expanded than at El Kef (Tunisia) [the Global Stratotype Section
and Point (GSSP) for the Cretaceous/Paleogene (K/Pg) boundary] or at Elles (Tunisia) [its auxiliary section].
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Chitons (Mollusca: Polyplacophora) from the Middle Miocene sandy facies of Ukraine, Central Paratethys
BARBARA STUDENCKA1, ALFRÉD DULAI2
1Museum of the Earth, Polish Academy of Sciences, Aleja Na Skarpie 20/26, PL-00-488 Warsaw, Poland.
bstudencka@go2.pl
2Department of Palaeontology and Geology, Hungarian Natural History Museum, H-1431 Budapest P.O.B. 137, Hungary.
dulai@nhmus.hu
ABSTRACT:The Late Badenian (=early Serravallian of the Mediterranean) chitons of Ukraine, housed in the Museum of the
Earth PAS, Warsaw, are described systematically. Eight species are identified: Leptochiton cancellatus (Sowerby,
1840), Lepidopleurus cajetanus (Poli, 1791), Ischnochiton rissoi (Payraudeau, 1826), Chiton corallinus (Risso,
1826), Chiton olivaceus Spengler, 1797, Lepidochitona lepida (Reuss, 1860), Acanthochitona faluniensis
(Rochebrune, 1883) and Craspedochiton profascicularis (Boettger, 1906). Most of the material comes from
Varovtsi, in the Khmelnytskyi region. The predominant faunal element is Acanthochitona faluniensis, comprising
55% of all investigated valves.
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A goniasterid starfish (Echinodermata, Asteroidea) preserved in a mid-Miocene rhyolitic ignimbrite, northwest Romania
JOHNW. M. JAGT1, VLAD CODREA2
1Natuurhistorisch Museum Maastricht, de Bosquetplein 6-7, NL-6211 KJ Maastricht, the Netherlands.
john.jagt@maastricht.nl
2Universitatea Babes-Bolyai, Catedra de Geologie-Paleontologie, Kogãlniceanu St 1, RO-400084 Cluj-Napoca, Romania.
codrea_vlad@yahoo.fr
ABSTRACT: A well-preserved, near-complete goniasterid asteroid, provisionally referred to the genus Ceramaster, is recorded
from a rhyolitic ignimbrite assigned to the Dej Tuff Formation, exposed near Ciceu Giurgesti (northwest Romania).
The main interest of this specimen lies in the fact that it constitutes a rare example of preservation of
(shallow-) marine biota, and echinoderms in particular, in volcanic strata. Superficially, overall disc shape and
size, as well as ornament of marginal and abactinal ossicles, resemble to some extent that of coeval and slightly
younger material from the Paratethys (south-central Poland, Austria) and the North Sea Basin (northwest Belgium),
previously assigned to Ceramaster. So far, only the Polish and Austrian material has been formally named;
however, this might actually represent but a single species. The record from Belgium refers to a form which is
either conspecific with C. muelleri from the Paratethys, or represents a closely related taxon. These, and associated
asteroids (e.g., Astropectinidae, Luidiidae), are in need of a modern taxonomic revision and a reappraisal
of their palaeoecology is called for as well.
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Multi-stage development of the joint network in the flysch rocks of western Podhale (InnerWestern Carpathians, Poland)
MIROSLAW LUDWINIAK
Institute of Geology, University of Warsaw, Zwirki i Wigury Str. 93, PL-02-089 Warszawa, Poland.
Miroslaw.Ludwiniak@uw.edu.pl
ABSTRACT: The geometry and morphology of joints have been examined in the flysch rocks in the western part of the Podhale
synclinorium. They form a regular network, which has been developed in several stages connected with the
structural evolution of the synclinorium.
The initiation of the oldest diagonal system (DR, DL sets), in the form of strength anisotropy in horizontal
beds, took place during the successive increase in NNE–SSWcompression. The formation of the majority of the
L’ set and of a small portion of the L set took place during gentle open folding connected with the setting of the
general structural framework of the synclinorium. The beginning of the formation of the T set was related to
WNW–ESE extension connected with the uplift of the synclinorium. The youngest joints – the majority of the
L and a small portion of the L’ set, were formed as the result of stress relaxation in the rock masses during progressive
uplift lasting up to recent times. The formation of the joints proceeded in two stages: (I) their initiation
in the form of joint-anisotropy and (II) opening of joints. These stages have often been significantly separated
in time. Sometimes the process of joint opening continues up to recent times.
There is a regional tendency that the double shear angle (2Θ) values increase from the axial zone towards
the marginal parts of the synclinorium, as well as downward in the flysch lithostratigraphic section. This is probably
caused by the increase in confining pressure and rock ductility attributed to the increase in overburden
load. The 2Θ values could also have been controlled by tectonic factors.
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