Large Upper Devonian Arthrodires from Iran
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FISHING for DUNKLEOSTEUS You’Re Definitely Gonna Need a Bigger Boat by Mark Peter
OOhhiioo GGeeoollooggyy EEXXTTRRAA July 31, 2019 FISHING FOR DUNKLEOSTEUS You’re definitely gonna need a bigger boat by Mark Peter At an estimated maximum length of 6 to 8.8 meters (20–29 sediments that eroded from the Acadian Mountains, combined feet), Dunkleosteus terrelli (Fig. 1) would have been a match for with abundant organic matter from newly evolved land plants even the Hollywood-sized great white shark from the and marine plankton, settled in the basin as dark organic movie Jaws. Surfers, scuba divers, and swimmers can relax, muds. Over millions of years, accumulation of additional however, because Dunkleosteus has been extinct for nearly 360 overlying sediments compacted the muds into black shale rock. million years. Dunkleosteus was a placoderm, a type of armored The rocks that formed from the Late Devonian seafloor fish, that lived during the Late Devonian Period from about sediments (along with fossils of Dunkleosteus) arrived at their 375–359 million years ago. Fossil remains of the large present location of 41 degrees north latitude after several species Dunkleosteus terrelli are present in the Cleveland hundred million years of slow plate tectonic movement as the Member of the Ohio Shale, which contains rocks that are North American Plate moved northward. approximately 360–359 million years old. Figure 1. A reconstruction of a fully-grown Dunkleosteus terrelli, assuming a length of 29 feet, with angler for scale. Modified from illustration by Hugo Salais of Metazoa Studio. Dunkleosteus cruised Late Devonian seas and oceans as an Figure 2. Paleogeographic reconstruction of eastern North America during apex predator, much like the great white shark of today. -
'Placoderm' (Arthrodira)
Jobbins et al. Swiss J Palaeontol (2021) 140:2 https://doi.org/10.1186/s13358-020-00212-w Swiss Journal of Palaeontology RESEARCH ARTICLE Open Access A large Middle Devonian eubrachythoracid ‘placoderm’ (Arthrodira) jaw from northern Gondwana Melina Jobbins1* , Martin Rücklin2, Thodoris Argyriou3 and Christian Klug1 Abstract For the understanding of the evolution of jawed vertebrates and jaws and teeth, ‘placoderms’ are crucial as they exhibit an impressive morphological disparity associated with the early stages of this process. The Devonian of Morocco is famous for its rich occurrences of arthrodire ‘placoderms’. While Late Devonian strata are rich in arthrodire remains, they are less common in older strata. Here, we describe a large tooth-bearing jaw element of Leptodontich- thys ziregensis gen. et sp. nov., an eubrachythoracid arthrodire from the Middle Devonian of Morocco. This species is based on a large posterior superognathal with a strong dentition. The jawbone displays features considered syna- pomorphies of Late Devonian eubrachythoracid arthrodires, with one posterior and one lateral row of conical teeth oriented postero-lingually. μCT-images reveal internal structures including pulp cavities and dentinous tissues. The posterior orientation of the teeth and the traces of a putative occlusal contact on the lingual side of the bone imply that these teeth were hardly used for feeding. Similar to Compagopiscis and Plourdosteus, functional teeth were pos- sibly present during an earlier developmental stage and have been worn entirely. The morphological features of the jaw element suggest a close relationship with plourdosteids. Its size implies that the animal was rather large. Keywords: Arthrodira, Dentition, Food web, Givetian, Maïder basin, Palaeoecology Introduction important to reconstruct character evolution in early ‘Placoderms’ are considered as a paraphyletic grade vertebrates. -
Contributions in BIOLOGY and GEOLOGY
MILWAUKEE PUBLIC MUSEUM Contributions In BIOLOGY and GEOLOGY Number 51 November 29, 1982 A Compendium of Fossil Marine Families J. John Sepkoski, Jr. MILWAUKEE PUBLIC MUSEUM Contributions in BIOLOGY and GEOLOGY Number 51 November 29, 1982 A COMPENDIUM OF FOSSIL MARINE FAMILIES J. JOHN SEPKOSKI, JR. Department of the Geophysical Sciences University of Chicago REVIEWERS FOR THIS PUBLICATION: Robert Gernant, University of Wisconsin-Milwaukee David M. Raup, Field Museum of Natural History Frederick R. Schram, San Diego Natural History Museum Peter M. Sheehan, Milwaukee Public Museum ISBN 0-893260-081-9 Milwaukee Public Museum Press Published by the Order of the Board of Trustees CONTENTS Abstract ---- ---------- -- - ----------------------- 2 Introduction -- --- -- ------ - - - ------- - ----------- - - - 2 Compendium ----------------------------- -- ------ 6 Protozoa ----- - ------- - - - -- -- - -------- - ------ - 6 Porifera------------- --- ---------------------- 9 Archaeocyatha -- - ------ - ------ - - -- ---------- - - - - 14 Coelenterata -- - -- --- -- - - -- - - - - -- - -- - -- - - -- -- - -- 17 Platyhelminthes - - -- - - - -- - - -- - -- - -- - -- -- --- - - - - - - 24 Rhynchocoela - ---- - - - - ---- --- ---- - - ----------- - 24 Priapulida ------ ---- - - - - -- - - -- - ------ - -- ------ 24 Nematoda - -- - --- --- -- - -- --- - -- --- ---- -- - - -- -- 24 Mollusca ------------- --- --------------- ------ 24 Sipunculida ---------- --- ------------ ---- -- --- - 46 Echiurida ------ - --- - - - - - --- --- - -- --- - -- - - --- -
Copyrighted Material
06_250317 part1-3.qxd 12/13/05 7:32 PM Page 15 Phylum Chordata Chordates are placed in the superphylum Deuterostomia. The possible rela- tionships of the chordates and deuterostomes to other metazoans are dis- cussed in Halanych (2004). He restricts the taxon of deuterostomes to the chordates and their proposed immediate sister group, a taxon comprising the hemichordates, echinoderms, and the wormlike Xenoturbella. The phylum Chordata has been used by most recent workers to encompass members of the subphyla Urochordata (tunicates or sea-squirts), Cephalochordata (lancelets), and Craniata (fishes, amphibians, reptiles, birds, and mammals). The Cephalochordata and Craniata form a mono- phyletic group (e.g., Cameron et al., 2000; Halanych, 2004). Much disagree- ment exists concerning the interrelationships and classification of the Chordata, and the inclusion of the urochordates as sister to the cephalochor- dates and craniates is not as broadly held as the sister-group relationship of cephalochordates and craniates (Halanych, 2004). Many excitingCOPYRIGHTED fossil finds in recent years MATERIAL reveal what the first fishes may have looked like, and these finds push the fossil record of fishes back into the early Cambrian, far further back than previously known. There is still much difference of opinion on the phylogenetic position of these new Cambrian species, and many new discoveries and changes in early fish systematics may be expected over the next decade. As noted by Halanych (2004), D.-G. (D.) Shu and collaborators have discovered fossil ascidians (e.g., Cheungkongella), cephalochordate-like yunnanozoans (Haikouella and Yunnanozoon), and jaw- less craniates (Myllokunmingia, and its junior synonym Haikouichthys) over the 15 06_250317 part1-3.qxd 12/13/05 7:32 PM Page 16 16 Fishes of the World last few years that push the origins of these three major taxa at least into the Lower Cambrian (approximately 530–540 million years ago). -
Redescription of Yinostius Major (Arthrodira: Heterostiidae) from the Lower Devonian of China, and the Interrelationships of Brachythoraci
bs_bs_banner Zoological Journal of the Linnean Society, 2015. With 10 figures Redescription of Yinostius major (Arthrodira: Heterostiidae) from the Lower Devonian of China, and the interrelationships of Brachythoraci YOU-AN ZHU1,2, MIN ZHU1* and JUN-QING WANG1 1Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China 2University of Chinese Academy of Sciences, Beijing 100049, China Received 29 December 2014; revised 21 August 2015; accepted for publication 23 August 2015 Yinosteus major is a heterostiid arthrodire (Placodermi) from the Lower Devonian Jiucheng Formation of Yunnan Province, south-western China. A detailed redescription of this taxon reveals the morphology of neurocranium and visceral side of skull roof. Yinosteus major shows typical heterostiid characters such as anterodorsally positioned small orbits and rod-like anterior lateral plates. Its neurocranium resembles those of advanced eubrachythoracids rather than basal brachythoracids, and provides new morphological aspects in heterostiids. Phylogenetic analysis based on parsimony was conducted using a revised and expanded data matrix. The analysis yields a novel sce- nario on the brachythoracid interrelationships, which assigns Heterostiidae (including Heterostius ingens and Yinosteus major) as the sister group of Dunkleosteus amblyodoratus. The resulting phylogenetic scenario suggests that eubrachythoracids underwent a rapid diversification during the Emsian, representing the placoderm response to the Devonian Nekton Revolution. The instability of the relationships between major eubrachythoracid clades might have a connection to their longer ghost lineages than previous scenarios have implied. © 2015 The Linnean Society of London, Zoological Journal of the Linnean Society, 2015 doi: 10.1111/zoj.12356 ADDITIONAL KEYWORDS: Brachythoraci – Heterostiidae – morphology – phylogeny – Placodermi. -
University of Michigan University Library
CONTBZBUTIONS FROM THE MUSEUM OF PAIZONTOLOGY (Contin& of Cmfrom lirs Mweum of Gsologg) UNIVERSITY OF MICHIGAN VOL. LII, No. 9, pp. 163-182 (6 pls., 13 text figs.) DECEMBEB18,1931 ARTHRODIRAN REMAINS FROM THE DEVONIAN OF MICHIGAN BY E. C. CASE UNIVERSITY OF MICHIGAN PRESS ANN ARBOR AllM SCANNER TEST CHART#2 Spectra 4 Pi ABCDEFGHIJKLM~~OPORSTUWXYZ~~~~~~~~~~~~~~OP~~~~~~Y~". /?SO123456768 Times Roman 4 PT ABCDEFOHIIKLUNOPQRSTLVWXYZ~~~~~~~~~~~~~~~~~P~P~~~~WX~Y/1601234567%9 6 PT ABCDEFGH1JKLMN0PQRSTUVWXYZabcdefgh1jklmnopqstuvwxyz", /1$0123456789 8 PT ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefgh1jklmnopqrstuvwxyz;:",./?$Ol23456789 10 PT ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz;:",./?$Ol23456789 / Century Schoolbook Bold 4 FT ABCDEFCHIJKLINOPQRSTUVWXYZ~~~~~~~~~~II~~~~~::',.'?M~~~S~~~~~~ 6 PT ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefahiiklmno~arstuvwxvz::'~../?$Ol23456l89 Bodoni Italic (H(I,PfLIII/kI &!>OIPX5?L i UXl/.td,fghc,rhuUn nqyr~ii,t lii /ablZlii(lP ABCDEFGHIJKLMNOPQRSTUVIYXYZ(I~~~~~~~~~~I~~~~~~~~IL~~,, /'SO123456789 A BCDEFGHIJKLMNOPQRSTUVWX YZabcdefghijklmnopyrstuuxyz;:",./?$0123456789 ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefgh~klmnopqrstueu;xyz;:';./?SO Greek and Math Symbols AB~IEI~HIK~MNO~~~PITY~~XVLLP)ISS~B~~~A~UO~~~PPPPX~~~-,5*=+='><><i'E =#"> <kQ)<G White Black Isolated Characters 65432 A4 Page 6543210 MESH HALFTONE WEDGES A4 Page 6543210 665432 ROCHESTER INSTITUTE OF TECHNOLOGY, ONE LOME CT W s E38L SEE 9 ~~~~ 2358 zgsp EH2 t 3ms 8 2 3 & sE2Z 53EL B83L BE3 9 2::: 2::: 285 9 gg,Bab EE 2 t s3zr BBE & :/; E 3 5 Z 32EL d SB50 CONTRIBUTIONS FROM THE MUSEUM OF PALEONTOLOGY --- (Continuation of Contributions from the Museum of Geology) UNIVERSITY OF MICHIGAN Editor: EUGENES. MCCARTNEY The series of contributions from the Museum of Paleontology was inaugurated to provide a medium for the publication of papers based entirely or principally upon the collections in the l$useum. When the number of pages issued is sufficient to make a volume, a title-page and a table of contents will be sent to libraries on the mailing list, and also to individuals upon request. -
The Earliest Phyllolepid (Placodermi, Arthrodira) from the Late Lochkovian (Early Devonian) of Yunnan (South China)
Geol. Mag. 145 (2), 2008, pp. 257–278. c 2007 Cambridge University Press 257 doi:10.1017/S0016756807004207 First published online 30 November 2007 Printed in the United Kingdom The earliest phyllolepid (Placodermi, Arthrodira) from the Late Lochkovian (Early Devonian) of Yunnan (South China) V. DUPRET∗ &M.ZHU Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, P.O. Box 643, Xizhimenwai Dajie 142, Beijing 100044, People’s Republic of China (Received 1 November 2006; accepted 26 June 2007) Abstract – Gavinaspis convergens, a new genus and species of the Phyllolepida (Placodermi: Arthrodira), is described on the basis of skull remains from the Late Lochkovian (Xitun Formation, Early Devonian) of Qujing (Yunnan, South China). This new form displays a mosaic of characters of basal actinolepidoid arthrodires and more derived phyllolepids. A new hypothesis is proposed concerning the origin of the unpaired centronuchal plate of the Phyllolepida by a fusion of the paired central plates into one single dermal element and the loss of the nuchal plate. A phylogenetic analysis suggests the position of Gavinaspis gen. nov. as the sister group of the Phyllolepididae, in a distinct new family (Gavinaspididae fam. nov.). This new form suggests a possible Chinese origin for the Phyllolepida or that the common ancestor to Phyllolepida lived in an area including both South China and Gondwana, and in any case corroborates the palaeogeographic proximity between Australia and South China during the Devonian Period. Keywords: Devonian, China, Placodermi, phyllolepids, biostratigraphy, palaeobiogeography. 1. Introduction 1934). Subsequently, they were considered as either sharing an immediate common ancestor with the The Phyllolepida are a peculiar group of the Arthrodira Arthrodira (Denison, 1978), belonging to the Actin- (Placodermi), widespread in the Givetian–Famennian olepidoidei (Long, 1984), or being of indetermined of Gondwana (Australia, Antarctica, Turkey, South position within the Arthrodira (Goujet & Young,1995). -
A Large Late Devonian Arthrodire (Vertebrata, Placodermi) from Poland
Estonian Journal of Earth Sciences, 2018, 67, 1, 33–42 https://doi.org/10.3176/earth.2018.02 A large Late Devonian arthrodire (Vertebrata, Placodermi) from Poland Piotr Szreka and Olga Wilkb a Polish Geological Institute–National Research Institute, 4 Rakowiecka Street, 00-975 Warszawa, Poland; [email protected] b Faculty of Geology, University of Warsaw, 93 Żwirki i Wigury Street, 02-089 Warszawa, Poland; [email protected] Received 1 August 2017, accepted 31 October 2017, available online 19 January 2018 Abstract. The arthrodire placoderm, Dunkleosteus sp., is reported from the Upper Devonian (Frasnian) of the Holy Cross Mountains, Poland. The material comprises partially preserved remains of two individuals found in the Kellwasser-like horizon of the Płucki locality. The remains are preserved as broken bone fragments redeposited from shallower environment into deep-shelf conditions. They are labelled as Dunkleosteus sp. and seem similar to Dunkleosteus marsaisi from the Famennian of Morocco. It is likely that the form from Poland represents a new species that requires further collecting and study of new specimens. The described specimens are the oldest occurrence of the genus Dunkleosteus in Europe, the most complete one from Poland and one of the biggest placoderms with a head about 60 cm long. Key words: Dunkleosteus, Upper Devonian, Frasnian, Holy Cross Mountains, Poland. INTRODUCTION D. marsaisi Lehman, 1954 from the early Famennian of Morocco (Lehman 1956). The genus Dunkleosteus (formerly Dinichthys in part) Although tens of placoderm fossil remains were includes about eight species (if including D. belgicus collected in Płucki during long-term excavation works (Leriche), 1931) which are found in Laurussia (USA, between 1996 and 2006 (see Szrek 2008, 2009; Szrek & Canada, Belgium, Poland) and Gondwana (Morocco). -
Devonian Daniel Childress Parkland College
Parkland College A with Honors Projects Honors Program 2019 Did You Know: Devonian Daniel Childress Parkland College Recommended Citation Childress, Daniel, "Did You Know: Devonian" (2019). A with Honors Projects. 252. https://spark.parkland.edu/ah/252 Open access to this Poster is brought to you by Parkland College's institutional repository, SPARK: Scholarship at Parkland. For more information, please contact [email protected]. GENUS PHYLUM CLASS ORDER SIZE ENVIROMENT DIET: DIET: DIET: OTHER D&D 5E “PERSONAL NOTES” # CARNIVORE HERBIVORE SIZE ACANTHOSTEGA Chordata Amphibia Ichthyostegalia 58‐62 cm Marine (Neritic) Y ‐ ‐ small 24in amphibian 1 ACICULOPODA Arthropoda Malacostraca Decopoda 6‐8 cm Marine (Neritic) Y ‐ ‐ tiny Giant Prawn 2 ADELOPHTHALMUS Arthropoda Arachnida Eurypterida 4‐32 cm Marine (Neritic) Y ‐ ‐ small “Swimmer” Scorpion 3 AKMONISTION Chordata Chondrichthyes Symmoriida 47‐50 cm Marine (Neritic) Y ‐ ‐ small ratfish 4 ALKENOPTERUS Arthropoda Arachnida Eurypterida 2‐4 cm Marine (Transitional) Y ‐ ‐ small Sea scorpion 5 ANGUSTIDONTUS Arthropoda Malacostraca Angustidontida 6‐9 cm Marine (Pelagic) Y ‐ ‐ small Primitive shrimp 6 ASTEROLEPIS Chordata Placodermi Antiarchi 32‐35 cm Marine (Transitional) Y ‐ Y small Placo bottom feeder 7 ATTERCOPUS Arthropoda Arachnida Uraraneida 1‐2 cm Marine (Transitional) Y ‐ ‐ tiny Proto‐Spider 8 AUSTROPTYCTODUS Chordata Placodermi Ptyctodontida 10‐12 cm Marine (Neritic) Y ‐ ‐ tiny Half‐Plate 9 BOTHRIOLEPIS Chordata Placodermi Antiarchia 28‐32 cm Marine (Neritic) ‐ ‐ Y tiny Jawed Placoderm 10 -
Facies Differentiation and Late Devonian Placoderms Fossils in the Holy Cross Mountains
Przegl¹d Geologiczny, vol. 54, nr 6, 2006 Zró¿nicowanie facjalne a skamienia³oœci póŸnodewoñskich plakodermów w Górach Œwiêtokrzyskich Piotr Szrek* Facies differentiation and Late Devonian placoderms fossils in the Holy Cross Mountains. Prz. Geol., 54: 521–524. S u m m a r y. Main Late Devonian placoderm taxa known from the Holy Cross Mountains are characterised. The distribution of the Late Devonian placoderm fossils is described. Variation in their occurrences depend on the sedimentation environment of the rocks which contain fossils of this group. Connections between the Holy Cross Mountains placoderms development and the synsedimentary tectonic processes active in this area during the Late Devonian is discussed, and the local faunas compared to classic assemblages of the same age from Latvia. Key words: Placodermi, synsedimentation tectonic, Late Devonian, facies, Holy Cross Mountains Placodermi (ryby pancerne) to gromada krêgowców Plakodermy œwiêtokrzyskie wodnych, która pojawi³a siê w sylurze, a wymar³a z koñcem dewonu. Ich maksymalny stopieñ zró¿nicowania Znalezione i opisane dotychczas póŸnodewoñskie pla- przypada na póŸny dewon — wtedy to plakodermy zdomi- kodermy z Gór Œwiêtokrzyskich mo¿na podzieliæ na dwie nowa³y niemal wszystkie morskie nisze ekologiczne, zasadnicze grupy. Kryterium zastosowanego podzia³u jest wytwarzaj¹c ró¿norodne typy specjalizacyjne, umo¿li- sposób zdobywania po¿ywienia oraz stopieñ przywi¹zania wiaj¹ce ¿ycie zarówno w otwartym basenie morskim, œro- do okreœlonych œrodowisk, a tak¿e stopieñ opancerzenia dowisku przyrafowym, jak te¿ w œrodowiskach cia³a. brakicznych. W Górach Œwiêtokrzyskich grupa ta jest Do pierwszej grupy mo¿na zaliczyæ wszystkie pla- bogato reprezentowana w materiale kopalnym i by³a oma- kodermy, bêd¹ce aktywnymi myœliwymi, u których pancerz wiana w licznych pracach od ponad stu lat (m.in. -
Société Géologique Nord
Société Géologique Nord 3 1 JAN. ?00D ANNALES Tome 7(2'me série), Fascicule 3 parution 1999 IRIS - LILLIAD - Université Lille 1 SOCIÉTÉ GÉOLOGIQUE DU NORD Extraits des Statuts Article 2 - Cette Société a pour objet de concourir à l'avancement de la géologie en général, et particulièrement de la géologie de la région du Nord de la France. - La Société se réunit de droit une fois par mois, sauf pendant la période des vacances. Elle peut tenir des séances extraordinaires décidées par le Conseil d'Administration. - La Société publie des Annales et des Mémoires. Ces publications sont mises en vente selon un tarif établi par le Conseil. Les Sociétaires bénéficient d'un tarif préférentiel 0 ). Articles Le nombre des membres de la Société est illimité. Pour faire partie de la Société, il faut s'être fait présenter dans l'une des séances par deux membres de la Société qui auront signé la présentation, et avoir été proclamé membre au cours de la séance suivante. Extraits du Règlement Intérieur § 7. - Les Annales et leur supplément constituent le compte rendu des séances. § 13. - Seuls les membres ayant acquitté leurs cotisation et abonnement de l'année peuvent publier dans les Annales. L'ensemble des notes présentées au cours d'une même année, par un auteur, ne peut dépasser le total de 8 pages, 1 planché simili étant comptée pour 2 p. 1/2 de texte. Le Conseil peut par décision spéciale, autoriser la publication de notes plus tangues. § 17. - Les notes et mémoires originaux (texte et illustration) communiqués à la Société et destinés aux Annales doivent être remis au Secrétariat le jour même de leur présentation. -
Vertebrata: Placodermi) from the Famennian of Belgium
View metadata, citationGEOLOGICA and similar papers BELGICA at core.ac.uk (2005) 8/1-2: 51-67 brought to you by CORE provided by Open Marine Archive A NEW GROENLANDASPIDID ARTHRODIRE (VERTEBRATA: PLACODERMI) FROM THE FAMENNIAN OF BELGIUM Philippe JANVIER1, 2 and Gaël CLÉMENT1 1. UMR 5143 du CNRS, Département «Histoire de la Terre», Muséum National d’Histoire Naturelle, 8 rue Buff on, 75005 Paris, France. [email protected] 2. 7 e Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom (9 fi gures, 1 table and 2 plates) ABSTRACT. A new species of the arthrodire genus Groenlandaspis is described from the upper part of the Evieux Formation (Upper Famennian), based on several specimens collected from quarries at Modave and Villers-le-Temple, Liège Province, Belgium. It is the fi rst occurrence of this widespread genus in continental Europe. O is new species is characterized by an almost smooth dermal armour, except for some scattered tubercles on its skull roof, median dorsal and spinal plates. Its median dorsal plate is triangular in shape and almost perfectly equilateral in lateral aspect and bears large, spiniform denticles on its posterior edge. All these Groenlandaspis remains occur in micaceous, dolomitic claystones or siltstones probably deposited in a subtidal environment. Outcrops of the same area have yielded other vertebrate remains, such as the placoderms Phyllolepis and Bothriolepis, acanthodians, various piscine sarcopterygians (Holoptychius, dipnoans, a rhizodontid, Megalichthys, Eusthenodon and a large tristichopterid), and a tetrapod that is probably close to Ichthyostega. O e biogeographical history of the genus Groenlandaspis is briefl y outlined, and the late Frasnian-Famennian interchange of vertebrate taxa between Gondwana and Euramerica is discussed.