Review of the reptilia of the triassic
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These remains of cervical vertebrae and phalanges give no information on the phylogeny of the Pterosauria. At most one could regard the cervical vertebrae as further proof that the long-tailed Pterosauria are older than the short-tailed pterodactyls (1). But these remains, even the oldest, leave us quite in the dark as to which reptile order the Pterosauria are derived from. C. SYSTEMATIC REVIEW OF THE TRIASSIC REPTILIA The Reptilia of the Triassic, as dealt with briefly in the foregoing, present a surprising diversity. All groups of Reptilia are represented already in the Triassic, except for the Ophidia, Pythonomorpha, and true Lacertilia. In the following I have classified all the genera of Triassic Reptilia in systematic arrangement. The surprisingly high number of 155 arises. Synonyms, as far as possible, are considered; otherwise the number would not increase significantly. It arises from: Stegocephalia 21 genera Anomodontia 64 “ Sauropterygia 18 “ Testudinata 3 “ Rhynchocephalia 1 genus Ichthyopterygia 3 genera Proganosauria 1 genus Parasuchia 15 genera Eusuchia 3 (?) “ Dinosauria 24 “ Pterosauria 2 (?) “ The systematic arrangement differs from ZITTEL and other textbooks. The Stegocephalia are dealt with briefly in the foregoing; I hope to come back to this in more detail on a later occasion. The Temnospondyli seem to me to stand very near the Pareiasauria and through them the Anomodontia in general. It is possible that they are derived from the former. In the classification of the Anomodontia I have followed SEELEY almost entirely, only the Endothiodontia are interpreted as a suborder (instead of family), for they depart further from the Theriodontia, Gorgonopsia, Dinocephalia, etc., than the latter do among themselves. They show agreement with the Rhynchosauria in so many points that they idea of a relationship can hardly be avoided, despite the double temporal fossa of the latter. Therefore they are placed beside each other in the table. Only Telerpeton is listed as a “rhynchocephalian”; perhaps it represents a connecting link between certain temnospondylous Stegocephalia and the Pleurosauridae; thus it is excluded from the true Rhynchocephalia. The Rhynchosauria are dealt with in relation to the Endothiodontia, and Mesosaurus is placed in the Sauropterygia. The Mesosauria and Plesiosauria are placed side-by-side, because Mesosaurus-Proneusticosaurus-Plesiosaurus seems to form a direct line forming the stem of the Sauropterygia; the other line, which develops rapidly into higher forms but remains confused in the Triassic, was Mesosaurus-Proneusticosaurus-Cymatosaurus, etc.-Nothosaurus; I do not believe that the Plesiosauridae are descended from the Nothosauridae. STEGOCEPHALIA TEMNOSPONDYLI Eryops COPE Karroo South Africa (1) Eupelor COPE Upper Triassic North America Pariostegos COPE “ “ “ “ Dictyocephalus COPE “ “ “ “ Petrophryne OWEN Karroo South Africa (= Micropholis HUXLEY) Xestorhytias HUXLEY Maleri Sandstone India Gondwanosaurus LYDEKKER “ “ “ “ Brachyops OWEN “ “ “ “ Bothriceps HUXLEY Triassic Australia Trochanterium v. HUENE Upper Muschelkalk Lorraine Eurycervix v. HUENE Lower Muschelkalk Upper Silesia Upper Muschelkalk Swabia STEREOSPONDYLI
(= Odontosaurus H. v. MEYER) Cyclotosaurus E. FRAAS Keuper south Germany Mastodonsaurus JÄGER Bunter Sandstone-Keuper Germany, England Metopias H. v. MEYER Keuper south Germany Diadetognathus MIALL “ England Labyrinthodon OWEN “ “ Rhystidosteus OWEN Karroo South Africa Pachygonia HUXLEY Maleri Sandstone India Gonioglyptus HUXLEY “ “ “ ANOMODONTIA THEROSUCHIA PAREIASAURIA Pareiasauridae Pareiasaurus OWEN Permo-Triassic north Russia Karroo South Africa Anthodon OWEN “ “ “ Propappus OWEN “ “ “ Procolophonidae Procolophon OWEN “ “ “ Elginia E. T. NEWTON Triassic sandstone Elgin Sclerosaurus H. v. MEYER Upper Bunter Sandstone Basel (= Labyrinthodon WIEDERSHEIM; = Aristodesmus SEELEY) GORGONOPSIA
DINOCEPHALIA Delphinognathus OWEN “ “ “ Tapinocephalus OWEN “ “ “ (DEUTEROSAURIA) PLACODONTIA
(= Psephoderma H. v. MEYER = Psephosaurus E. FRAAS) England, France Pleurodon GÜRICH Lower Muschelkalk Upper Silesia Cyamodus H. v. MEYER Lower Muschelkalk “ “ Upper Muschelkalk Bayreuth Placochelys JAEKEL Keuper Plattensee Eunotosaurus SEELEY Karroo South Africa Clepsydropidae Ctenosaurus v. HUENE Middle Bunter Sandstone northwest Germany THERIODONTIA Lycosauria
(= Batrachosaurus) Basileosaurus* WIEDERSHEIM Upper Bunter Sandstone Basel Crurosaurus* v. HUENE Lower Muschelkalk prov. Saxony Actiosaurus* SAUVAGE Rhaetic France Cynodontia Cynognathus OWEN Karroo South Africa Galesaurus OWEN “ “ “ Nythosaurus OWEN “ “ “ Cynochampsa OWEN “ “ “ Herpetochirus SEELEY “ “ “ Tribolodon OWEN “ “ “ Dicranozygoma SEELEY “ “ “ Sceloposaurus OWEN “ “ “ Titanosuchus OWEN “ “ “ Thrinaxodon SEELEY “ “ “ Phocosaurus* OWEN “ “ “ Gomphodontia Gomphognathus SEELEY “ “ “ Microgomphodon SEELEY “ “ “ Trirachodon SEELEY “ “ “ Tritylodon SEELEY “ “ “ Diademodon SEELEY “ “ “ Theriodesmus SEELEY “ “ “ Microlestes PLIENINGER Middle Keuper England Rhaetic Württemberg ?Hypsiprymnopsis DAWKINS Middle and Upper Keuper England ?Triglyphus O. FRAAS Rhaetic Württemberg ENDOTHIODONTIA
?Rhynchosauridae Rhynchosaurus OWEN Middle Keuper England Hyperodapedon HUXLEY Triassic sandstone Elgin Middle Keuper England Maleri Sandstone India THEROCHELONIA DICYNODONTIA Dicynodontidae Dicynodon OWEN 1) Aulacocephalodon SEELEY Maleri Sandstone India 2) Rhachiacephalodon SEELEY Karroo South Africa
(= Pychosiagma LYDEKKER) Theriognathus OWEN “ “ “ Platypodosaurus OWEN “ “ “ Tropidosteus SEELEY “ “ “ Keirognathus OWEN “ “ “ (= Cirognathus SEELEY) Hyorhynchus SEELEY “ “ “ Eurycarpus SEELEY “ “ “ Gordonia E. T. NEWTON Triassic sandstone Elgin Permo-Triassic north Russia Anomosaurus* Lower, Middle, Upper Germany Muschelkalk Oudenodontidae
1) Aulacocephalus SEELEY Karroo South Africa 2) Rhachicephalus SEELEY “ “ “
Permo-Triassic north Russia KISTECEPHALIA
(= Cistecephalus LYDEKKER) Permo-Triassic north Russia SAUROPTERYGIA MESOSAURIA Mesosaurus GERVAIS Karroo South Africa (= Ditrochosaurus GÜRICH) Plesiosauridae
(= Termatosaurus PLIENINGER) Upper Muschelkalk Germany Lettenkohle south Germany Rhaetic south Germany, France, Switzerland, England Pistosauridae Pistosaurus H. v. MEYER Upper Muschelkalk Bayreuth Nothosauridae Cymatosaurus SCHRAMMEN Lower Muschelkalk Silesia, Saxony Eurysaurus FRECH “ “ Silesia Nothosaurus MÜNSTER Upper Muschelkalk Germany, Heligoland, (= Dracosaurus) France Lettenkohle Germany Cassian beds St. Cassian, Tyrol Conchiosaurus H. v. MEYER Middle Muschelkalk central Germany Opiosaurus H. v. MEYER Upper Muschelkalk central Germany Lamprosaurus H. v. MEYER Lower Muschelkalk Silesia Lariosaurus CURIONI Upper Muschelkalk Lombardy (= Macromirosaurus CURIONI) Parthanosaurus SKUPHOS Raibl beds Vorarlberg Microleptosaurus SKUPHOS Partnach beds “ Dasygnathus* HUXLEY Triassic sandstone Elgin TESTUDINATA CRYPTODIRA Chelyzoon v. HUENE Upper Muschelkalk Bayreuth, Crailsheim Arctosaurus ADAMS Triassic Bathurst Island (Arctic N. America) PLEURODIRA
(= Proganochelys BAUR; ? = Chelytherium H. v. HUENE) RHYNCHOCEPHALIA Telerpeton MANTELL Triassic sandstone Elgin ICHTHYOPTERYGIA Mixosaurus BAUR Lower Muschelkalk Germany, France Rhaetic England Raibl beds Besano
(= Rhachitrema SAUVAGE) Spitzbergen Ichthyosaurus BLAINEVILLE Upper Triassic PROGANOSAURIA ?Proterosaurus H. v. MEYER Middle Bunter Sandstone Bernberg PARASUCHIA Belodontidae Belodon H. v. MEYER Lettenkohle Germany, India, (= Phytosaurus JÄGER; Keuper Switzerland, = Palaeosaurus EMMONS; Rhaetic North America = Compsosaurus LEIDY; = Omosaurus LEIDY; = Eurydorus LEIDY; = Centemodon LEA) Mystriosuchus E. FRAAS Middle Keuper south Germany Stegomus MARSH Upper Triassic North America Rhytiodon EMMONS “ “ “ “ Stagonolepis AGASSIZ “ “ Elgin em. HUXLEY Saurodesmus* SEELEY (1) Rhaetic Scotland Rileya v. HUENE Middle Keuper England Parasuchus HUXLEY Maleri Sandstone India Episcoposaurus COPE Upper Triassic New Mexico PSEUDOSUCHIA Aëtosaurus O. FRAAS Middle Keuper Swabia Typothorax COPE (ex parte) Upper Triassic New Mexico Dyoplax O. FRAAS Lower Keuper Swabia Ornithosuchus E. T. NEWTON Triassic sandstone Elgin Erpetosuchus E. T. NEWTON “ “ “ Megalocnemus* BASSANI Raibl beds Lombardy EUSUCHIA Procerosaurus v. HUENE Upper Muschelkalk Swabia Pectenosaurus v. HUENE “ “ Franconia Div. gen. indet. Lower & Upper Muschelkalk Swabia, Lorraine DINOSAURIA THEROPODA Zanclodontidae
(= Smilodon PLIENINGER; England = Cladyodon OWEN; = Dimodosaurus PIDANCET & CHOPARD)
(= Avalonia SEELEY; Switzerland, = Picrodon SEELEY) England
(= Ankistrodon HUXLEY) Bathygnathus LEIDY Triassic Prince Edward Island (? = Teratosaurus H. v. MEYER) Euskelosaurus HUXLEY Upper Karroo South Africa Orosaurus HUXLEY “ “ “ “ (= Orinosaurus LYDEKKER) Anchisauridae
(= Amphisaurus MARSH; = Megadactylus HITCHCOCK; = Clepsysaurus LEA) Ammosaurus MARSH Upper Triassic Connecticut Thecodontosaurus OWEN Middle Keuper England Palaeosaurus OWEN “ “ “ Massospondylus OWEN Upper Triassic India Upper Karroo South Africa Pachyspondylus OWEN “ “ “ “ Leptospondylus OWEN “ “ “ “ Hortalotarsus SEELEY “ “ “ “ Agrosaurus SEELEY Upper Triassic Australia Palaeoctomus COPE “ “ South Carolina Zatomus COPE “ “ “ “ Suchoprion COPE “ “ “ “ two gen. nov. Lower & Upper Muschelkalk Germany ?Coeluridae
(= Macroscelosaurus MÜNSTER) Coelophysis COPE Upper Triassic New Mexico (1) ?Orthopoda Dystrophaeus COPE Triassic Utah, U.S.A. PTEROSAURIA “Pterodactylus” H. v. MEYER Rhaetic south Germany, England ?Tribelesodon BASSANI Raibl beds Lombardy D. DISTRIBUTION AND IMPORTANCE OF THE TRIASSIC REPTILIA In order to be better able to find our way through the 155 genera of Triassic Reptilia of the whole Earth, and to be better able to judge their faunistic, stratigraphic, and phylogenetic significance, we must once again review the whole host of them. We confine ourselves first to Europe. The oldest member of the central European Triassic, the Bunter Sandstone, contains among the scanty organic remains, most of which come from the dry land, several Stegocephalia and Anomodontia. Among the Stegocephalia, the exclusively Permian group of the Phyllospondyli and the mainly Permian group of the Temnospondyli are not represented in the Bunter Sandstone, but Stereospondyli are present. The locality of Bernberg (Middle Bunter Sandstone) in Thuringia is particularly well known for the numerous finds of Trematosaurus, which by the form of its head recalls the Permian Archerosaurus. Capitosaurus nasutus is also found there. Only one proterosaurid comes from Bernberg (see above). In the Voltzia Sandstone of Sulzbad, Alsace, a huge skull of a yet-unknown stereospondylous stegocephalian (similar to Capitosaurus nasutus) has been found; H. von MEYER’s Odontosaurus also comes from there (it is no more than a toothed jaw fragment from a Capitosaurus). Large thoracic armor plates have also been found. Poorly preserved fragments of Mastodonsaurus or Capitosaurus also occur in the region of Nagold in the Black Forest (2). The main Bunter Sandstone of Riehen near Basel has also yielded dorsal and head plates of Capitosaurus. Riehen and Warmbach near Rheinfelden are the only localities in which Anomodontia also occur in good preservation, namely Sclerosaurus (= Aristodesmus) and Basileosaurus. These true, high-limbed therosuchian Anomodontia, with characteristic dermal covering and head spines, are unknown in South Africa, the main home of the Anomodontia, but probably from north Russia and Elgin. The isolated occurrence of a clepsydropid, Ctenosaurus, in the Middle Bunter Sandstone of Göttingen, is very noteworthy and peculiar. Ctenosaurus, like its other relatives from the Permian (of Texas), is also distinguished by extraordinarily long spinal processes, which probably formed a high crest on the back. The great similarity of the head of Sclerosaurus with Elginia can justify the insertion of the fauna of the Elgin Sandstone in northeast Scotland into the discussion here. The yellow, poorly bedded sandstone of Morayshire apparently lies concordantly upon the upper red and yellowish Old Red. This contact is not exposed directly anywhere (1). The picturesquely wooded hills on the blue Moray Firth have numerous quarries developed. Even from some distance one can recognize the red color below and the yellow above. The quarries in the red sandstone yield numerous Upper Devonian fish, and because of this the entire sandstone complex was originally ranked in the Old Red. No more fish occur in the upppermost Bunter Sandstone, but in the course of time a very peculiar reptile fauna has been collected (already recognized as Triassic by HUXLEY) by HUXLEY, GORDON, GRANT, TRAQUAIR, TAYLOR, etc. Rock type and fauna are not the same in all quarries. The quartz-rich, extremely coarse, nearly conglomeratic sandstone of the southern half has only yielded Elginia, Gordonia, and Geikia (2). The fine sandstone of the region bordering the sea (3) contains very numerous Stagonolepis, Ornithosuchus, Erpetosuchus, Hyperodapedon, and Telerpeton (also a Ceratodus tooth). An arrangement and correlation of the sandstone with the different faunas is not to be observed, for they occur on entirely different hills; both seem to lie concordantly on the Old Red. Without some stratigraphic grounds to refer to, one has gained the impression from paleontological considerations that the sandstone with the Belodon-like Stagonolepis must be Upper Triassic. Ornithosuchus and Erpetosuchus are small parasuchian crocodiles which have their nearest relations in Aëtosaurus and Dyoplax from the Lower and Middle Keuper of Swabia. All other Parasuchia are Upper Triassic. Hyperodapedon is also very closely related with Rhynchosaurus from the Keuper of Warwickshire. On the other hand, the obviously very close relationship of Elginia with Sclerosaurus from the Bunter Sandstone could indicate an even greater antiquity. Gordonia, a dicynodont, probably stands nearest Ptychognathus, and Geikia is an oudenodont. These genera, according to SEELEY, are found in the lowest and middle Karroo of South Africa. Gordonia is common in the so-called Permian reptile fauna of north Russia; a skull of Geikia was also found there. According to this, the sandstone of Cuttie’s Hillock must be placed in the Lower Triassic. But the Stagonolepis sandstone can only be Upper Triassic, for the main distribution of the Parasuchia in southern and western England, the whole European continent, North America (Connecticut, South Carolina, New Mexico, etc.), and India is confined to the Upper and uppermost Triassic (Middle and Upper Keuper and Rhaetic). The idea of different ages of the Elginia sandstones is suggested on paleontological grounds; I know of no geological grounds in support of this, but certainly none is against it. The Middle Triassic German formation, the Muschelkalk, contains a whole host of mostly swimming reptiles; however, occasionally true land-dwellers are found. The latter appear again in greater numbers only toward the end of the Triassic in Europe, for the dry land again increased in area for a short time then. The Lower Muschelkalk at Sulzbad, Alsace, a sandy rock, has yielded a characteristic small fauna in poorly preserved remains. There are several armor plates of Stegocephalia, single-headed ribs that could belong to Sauropterygia or Anomodontia, and a piece of an upper vertebral arch from Anomosaurus HUENE (it has a strikingly long shaft, which measures 14 cm from point to point). In the Dadocrinus horizon (3 cm above the Röth) of the Lower Muschelkalk of Upper Silesia, there is a rich fauna in the same place. There, Capitosaurus silesiacus KUNISCH is found; a huge cervico-thoracic plate of another stegocephalian was found in the deepest Wellenkalk of the cement works near Halle am Saale; it is 40 cm broad and 30 cm long. It may be the same species at Sulzbad, Gogolin, and Halle. Then vertebrae of Tanystrophaeus and two other genera of Dinosauria are to be mentioned from Upper Silesia, of which one survived until the Lettenkohle. Cyamodus (tarnowitzensis GÜRICH) is to be interpreted as a coast dweller, which also lived in Silesia in the Lower Muschelkalk. Its pavement dentition enabled it to feed on thick-shelled Mollusca and Crustacea, which only lived in the shallow water and in the proximity of the shore; Placodus-like teeth also occur in the Lower Muschelkalk of Halle. Yet other remains, perhaps of land-living reptiles of the anomodont group, have been found in the Lower Muschelkalk of Upper Silesia (Gogolin). In Breslau there is part of a skeleton with walking feet and dermal ossifications. It will be described by Dr. VOLTZ soon. However, the main bulk of the reptile fauna of the Lower Muschelkalk of Upper Silesia and Saxony consists of Sauropterygia, which were true marine carnivores. The Nothosauridae play the greatest role, some of them very small forms; but already several Plesiosauridae were associated with them. The pygmy forms are Anarosaurus (Saxony) and Dactylosaurus (Silesia); already Proneusticosaurus is rather larger. They stand near the South African Mesosaurus and the Permian Stereosternum (São Paolo, Brazil) and are, so to speak, direct intermediates to the Plesiosauria. In the area of Jena this fauna begins as early as the Upper Röth. In the south German Lower Muschelkalk this pygmy fauna has still not been found. It is interesting to see that many Sauropterygia, such as Proneusticosaurus and Dactylosaurus, have limbs in which the reorganization of the walking “foot” to paddles apparently has not yet begun. Already the important genera Cymatosaurus and Eurysaurus (1) are larger than the oldest Nothosauridae. They are distinguished by the possession of a postorbital, which neither the true Nothosauria of the Upper Muschelkalk nor the Plesiosauria possess. Cymatosaurus occurs in the vicinity of Halle even in the lowest Muschelkalk. The structure of the skull (long tapering snout, position of the narial openings, etc.) shows that it, in particular Cymatosaurus friedericianus FRITSCH (2), is the forerunner of Pistosaurus. Vertebrae of true Plesiosauria also occur in the Lower Muschelkalk of Alt-Tarnowitz. They possess the characteristic foramina on the underside of the vertebrae. In addition to the sea-dominating Sauropterygia, the Ichthyopterygia also already occur in the Lower Muschelkalk; later, in the Liassic, they followed the long-necked Sauropterygia in supremacy. In the Swabian Wellenkalk the Ichthyosauria (Ichthyosaurus atavus QU.) occur as a large and small species, but which hitherto have not been sufficiently collected and described; it is possible that it is a question of Shastasaurus and Mixosaurus. An Ichthyosaurus (?Mixosaurus) also occurs in the Wellenkalk of Querfurt, North Marz, and a lower jaw has been found near the cement works at Halle am Saale that is probably Mixosaurus. |