Rainer R Schoch

State Museum of Natural History Stuttgart | SMNS · Department of Paleontology

The 330 million year history of amphibian evolution is full of interesting patterns, ranging from species-level changes to major evolutionary events and extinction. This chapter discusses some common patterns of macroevolution in fossil amphibians and then focuses on some of the major factors that have been identified in amphibian evolution. Althou...

Pappochelys extends the fossil record of Triassic stem-turtles back by some 20 million years and provides important new insights into how and in what sequence the key features of turtles arose. It shares various derived features with the early Late Triassic stem-turtle Odontochelys, such as T-shaped ribs, a short trunk, and features of the girdles...

Dissorophoid temnospondyls are widely considered to have given rise to some or all modern amphibians (Lissamphibia), but their ingroup relationships still bear major unresolved questions. An inclusive phylogenetic analysis of dissorophoids gives new insights into the large-scale topology of relationships. Based on a TNT 1.5 analysis (33 taxa, 108 c...

The origin of the unique body plan of turtles has long been one of the most intriguing mysteries in evolutionary morphology. Discoveries of several new stem-turtles, together with insights from recent studies on the development of the shell in extant turtles, have provided crucial new information concerning this subject. It is now possible to devel...

Significance The origin of modern amphibians remains controversial, and especially the fossil record of salamanders remains poor. Their tiny, feeble skeletons are rarely preserved in rocks of the early Mesozoic era, the time frame in which they are believed to have originated. Here we report 230 million-year-old fossils from Kyrgyzstan, Inner Asia,...

A large temnospondyl specimen from a lacustrine deposit of the early Permian Sperbersbach Lake horizon is recognized as a distinct new species , Memonomenos amelangi nov. sp. In addition to the type specimen (skull length 24.5 cm), two larval specimens were found that document the early stages of ontogeny. M. amelangi is referred to the genus Memo...

The Middle Triassic (Ladinian) fossil assemblages from the Lower Keuper localities of Vellberg-Eschenau and Kupferzell (Germany) are notable for their rich vertebrate fauna, including the earliest stem-turtle Pappochelys rosinae and the oldest rhynchocephalian Wirtembergia hauboldae. Among them, the largest temnospondyl known to date, Mastodonsauru...

Temnospondyls had a remarkable worldwide distribution throughout the Triassic at a time of periodic arid climates, and were a stable component of Triassic terrestrial ecosystems. Given the postulated ancestral relationship between temnospondyls and modern lissamphibians it is pertinent to recognize that the group may have exhibited some degree of e...

Paleopathology, the study of diseases and injuries from the fossil record, allows for a unique view into the life of prehistoric animals. Pathologies have nowadays been described in nearly all groups of fossil vertebrates, especially dinosaurs. Despite the large number of skeletons, pathologies had never been reported in the sauropodomorph Plateosa...

The 100 x 300 km Saar-Nahe Basin in SW Germany is one of the largest intramontane basins of the Variscan Belt. For more than 250 years, the cumulatively over 8,000-m-thick, volcano-sedimentary basin fill has been known for Pennsylvanian-Permian continental biota. A more recently recognized fossil site with abundant and diverse aquatic, semiaquatic...

The question of what the ancient life cycle of tetrapods was like forms a key component in understanding the origin of land vertebrates. The existence of distinct larval forms, as exemplified by many lissamphibians, and their transformation into adults is an important aspect in this field. The temnospondyls, the largest clade of Palaeozoic–Mesozoic...

Some of the earliest members of the archosaur-lineage (i.e., non-archosauriform archosauromorphs) are characterised by an extremely elongated neck. Recent fossil discoveries from the Guanling Formation (Middle Triassic) of southern China have revealed a dramatic increase in the known ecomorphological diversity of these extremely long-necked archosa...

The skull and postcranium of the Late Triassic plagiosaurid temnospondyl Plagiosaurus depressus from Halberstadt (Germany) are redescribed in detail. Plagiosaurus possesses two autapomorphies, the abbreviated tabular and the broad contact between the postorbital and parietal. A comprehensive phylogenetic analysis of Plagiosauridae finds a clade Pla...

Skeletal remains of a small lepidosaurian reptile from the Middle Triassic (Ladinian: Longobardian) Erfurt Formation, exposed in a commercial limestone quarry near Vellberg (Germany), represent the oldest rhynchocephalian known to date. The new taxon, Wirtembergia hauboldae , is diagnosed by the following combination of features: Premaxilla with fo...

The vertebrate water-to-land transition and the rise of tetrapods brought about fundamental changes for the groups undergoing these evolutionary changes (i.e. stem and early tetrapods). These groups were forced to adapt to new conditions, including the distinct physical properties of water and air, requiring fundamental changes in anatomy. Nutritio...

Reexamination of Mastodonsaurus (Heptasaurus) cappelensis, a three-metre long capito-saur temnospondyl from the Upper Buntsandstein (Anisian, Middle Triassic), reveals formerly poorly known or unrecognized features of this earliest mastodonsaurid temnospondyl. M. cappelensis differs from the stratigraphically younger type species M. giganteus in th...

The Branchiosauridae form a clade of tiny newt‐like, extinct amphibians of overall larval appearance. Although their status as neotenic (perennibranchiate) forms had long been universally accepted, adult specimens are known from only one taxon that was hitherto referred to as Melanerpeton ( Apateon ) gracile . Here we study this life cycle in depth...

We report the first trilophosaurid stem-archosaur from Central Europe, Rutiotomodon tytthos gen. et sp. nov., from the Middle Triassic (Ladinian) Erfurt Formation of Baden-Württemberg (Germany). It is currently known from two jaw fragments with distinctive teeth. The labiolingually wide but mesiodistally narrow maxillary and dentary teeth each have...

The slender-skulled temnospondyl Trematolestes hagdorni Schoch, 2006 forms a regular component of Lower Keuper lake faunas. New material extends the size range by larval, juvenile and large adult specimens, and also reveals new features of the palate, mandible and postcranium. In early juveniles, the head was wider but the ornament consistent with...

Newsletter Uni Tübingen aktuelle Nr. 4/2022: Leute (2 pages), https://uni-tuebingen.de/universitaet/aktuelles-und-publikationen/newsletter-uni-tuebingen-aktuell/2022/4/leute/7/

The Amphibamiformes, small temnospondyls from late Palaeozoic rocks, have been increasingly considered as the stem-group of some or all extant amphibians (Lissamphibia). Their relationships have become intensely studied after the discovery of new taxa and the revision of poorly known ones, but understanding is hampered by the fact that amphibamifor...

The Upper Triassic Keuper sequence yields many exceptional fossil localities in Germany and the former Central European Basin as a whole. With a time span of 35 million years, the Keuper is comprised of several different paleoenvironments represented in different lithostratigraphic formations. Fossil remains of temnospondyl amphibians can be seen a...

In 1977, within 3 months of excavation, a 500 m spanning road-cut near Kupferzell (southern Germany) produced a total of ~30,000 vertebrate remains from the Middle Triassic Lower Keuper. The bulk of the material stems from two temnospondyl amphibians, Gerrothorax pulcherrimus (~70%) and Mastodonsaurus giganteus (~30%), with the pseudosuchian archos...

The small, immature brachyopid stereospondyl Platycepsion wilkinsoni from the Early or Middle Triassic of Gosford, New South Wales, is redescribed from a developmental point of view. Whereas the sutural contact between postorbital and parietal suggested by earlier authors cannot be confirmed, a new autapomorphy, the posterior process of the intercl...

The Middle Triassic epoch witnessed a flourishing of ecosystems, with the radiation of several vertebrate lineages, eventually dominated by archosaurs. Fossil sites in terrestrial settings from this time interval, even if known from all continents, still hold unresolved questions regarding the evolution of faunas and their significance in the recov...

Trace fossils, or ichnofossils, are important elements to understand the relationships and interactions of trace makers with the environment and/or with other organisms. In this regard, bite traces (commonly also known as “bite marks”) provide direct evidence on the feeding habits and potentially the ecological role of the bite maker, even in the c...

Bite traces on fossil bones are key to deciphering feeding ecology and trophic interactions of vertebrate past ecosystems. However, similarities between traces produced by different carnivorous taxa with similar dentitions, and misidentifications due to equifinality, hinder confident identifications of the bite makers. Here, we correlate bite trace...

Parioxys ferricolus Cope, 1878 is a long-neglected taxon of dissorophid temnospondyls from the early Permian (Cisuralian) of Texas. Reexamination of the original material and preparation of a previously undescribed specimen shed some light on the ontogeny and reveal numerous eucacopine features. P. ferricolus is characterized by: (1) a preorbital r...

Triassic strata of the Economy Member of the Wolfville Formation (Newark Supergroup) exposed along the shorelines in Colchester County, Nova Scotia, have yielded an assemblage of continental tetrapods that is clearly different from other Triassic tetrapod communities in eastern North America, including the Late Triassic (Carnian) one from the overl...

We provide a detailed description of the poorly known reptile Eifelosaurus triadicus Jaekel, 1904 from the Upper Buntsandstein (Triassic: early Anisian) of Oberbettingen in the southwestern Eifel region of Rhineland-Palatinate, Germany. The holotype and only known specimen is a partial postcranial skeleton exposed in ventral view. Since its origina...

Plant (Pleuromeia, Lycopsid) and animals (Amphibian skulls) of the Lower Triassic

Plants (Pleuromeia) and amphibian skulls of the Lower Triassic of Germany

Eryopid temnospondyls were large apex predators in Carboniferous and Permian stream and lake habitats. The eryopid life cycle is exemplified by Onchiodon labyrinthicus from Niederhäslich (Saxony, Germany), which is represented by numerous size classes from small larvae to heavily ossified adults. Morphometric and principal component analyses provid...

The late Paleozoic temnospondyl Sclerocephalus formed an aquatic top predator in various central European lakes of the late Carboniferous and early Permian. Despite hundreds of specimens spanning a wide range of sizes, knowledge of the endocranium (braincase and palatoquadrate) remained very insufficient in Sclerocephalus and other stereospondylomo...

The Middle Triassic was an important time in the evolutionary history of reptiles because it was during this time that many modern groups originated and initially diversified. In this context, the rich fossiliferous deposits of the Ladinian-age Erfurt Formation in southern Germany play an important role in elucidating reptilian diversity during thi...

The Middle Triassic was a crucial time interval for vertebrate ecosystems, when they were recovering from the largest biotic crisis of Earth history, the end-Permian mass extinction. Vertebrate communities underwent a complete remodelling, the so-called modern faunas were established and the archosaur lineage dominated ecosystems. Here we present t...

The early Permian Meisenheim Formation of the Saar–Nahe Basin (Germany) is famous for its richness in vertebrate fossils, among which the temnospondyls were present with microvores and fish-eating apex predators. The latter trophic guild was occupied exclusively by the genus Sclerocephalus in that basin within a long time interval up to M8, whereas...

A small temnospondyl skull from the upper Carboniferous Allegheny Group of Five Points, Ohio, is referred to a new dissorophoid, Palodromeus bairdi n. gen n. sp. The complete skull with mandibles is preserved in counterparts. It is characterized by, (1) elongated slit-like choana; (2) postfrontal, postorbital, and supratemporal bearing a distinct r...

A new taxon of sphenodontian reptile, Micromenodon pitti new genus new species is described from the Upper Triassic (Carnian) Vinita Formation of the Richmond basin of the Newark Supergroup in Virginia. It is diagnosed by a dorsoventrally deep facial process of the maxilla that extends for almost the entire anteroposterior length of the bone and by...

In recent years photogrammetry has become an essential tool in the study of tetrapod footprints. Morphological analyses of footprints are interpretative; thus, researchers should use as much information as possible in order to eventually provide an objective conclusion. In this regard, photogrammetry is an extremely helpful tool to avoid potential...

Skeletal remains of a small reptile with a distinctive dentition from the Lower Keuper (Erfurt Formation; Middle Triassic, Ladinian) of the Schumann quarry near Eschenau, in the municipality of Vellberg in Baden-Württemberg, Germany, represent a new taxon of non-archosaurian archosauriforms, Polymorphodon adorfi. It is diagnosed by various craniode...

The diversity of the vertebrate cranial shape of phylogenetically related taxa allows conclusions on ecology and life history. As pleurodeline newts (the genera Echinotriton, Pleurodeles and Tylototriton) have polymorphic reproductive modes, they are highly suitable for following cranial shape evolution in relation to reproduction and envi- ronment...

the Middle triassic was a time of major changes in tetrapod faunas worldwide, but the fossil record for this interval is largely obscure for terrestrial faunas. this poses a severe limitation to our understanding on the earliest stages of diversification of lineages representing some of the most diverse faunas in the world today, such as lepidosaur...

Triassic temnospondyl amphibian tracks are relatively rare, in contrast with the body fossil record. Herein we report temnospondyl tracks from the base of the Anthrakonitbank carbonate bed, within the upper Middle Triassic Lower Keuper succession (Erfurt Formation) in the Vellberg Fossil-Lagerstätte of southern Germany. The sedimentary succession c...

Pacific giant salamanders (Dicamptodon) rank among the largest terrestrial caudates. Their ontogeny produces two distinct morphs—larval‐neotenic and metamorphosed—which differ in many morphological traits. We identified changes that are initiated by metamorphosis (distinguishing transformed from neotenic specimens) and also recognized age‐related c...

Fossils from the late Paleozoic continental Saar-Nahe Basin, SW Germany, have been known for more than 250 years. Despite the abundance and diversity of continental biota of Carboniferous-Permian age, there is still a significant lack of non-aquatic vertebrates from the basin. Recent discoveries in nearly 300 Ma (Gzhelian-Asselian) old fluvio-lacus...

Addressing the patterns of ontogenetic allometry is relevant to understand morphological diversification because allometry might constrain evolution to specific directions of shape change but also facilitate phenotypic differentiation along lines of least evolutionary resistance. Temnospondyl amphibians are a suitable group to address these issues...

Unlike any other tetrapod, turtles form their dorsal bony shell (carapace) not from osteoderms, but by contribution of the ribs and vertebrae that expand into the dermis to form plate-like shell components. Although this was known from embryological studies in extant turtles, important steps in this evolutionary sequence have recently been highligh...

The Late Palaeozoic temnospondyl Sclerocephalus haeuseri is known from numerous specimens and formations in the Lower Rotliegend sequence of the Saar-Nahe Basin, SW Germany. The type specimen was long believed to be lost, and therefore a neotype was determined. A diagnostic partial skull, curated in the paleontological collection of the University...

The stereospondylomorph temnospondyls form a diverse group of early tetrapods that survived the Permian–Triassic extinction event and radiated during the Triassic. They encompass Carboniferous and Permian taxa from central and eastern Europe, such as ‘archegosauroids’, and early-divergent Gondwanan forms, such as rhinesuchids. By the Early Triassic...

A complete skull and well-preserved postcranium of a dvinosaurian temnospondyl from the Carboniferous-Permian boundary of Germany is referred to a new genus and species, Trypanognathus remigiusbergensis. The skull closely resembles that of the early Permian dvinosaurian genus Trimerorhachis in outline and suture topology, but the occiput and the pa...

The slender-skulled temnospondyl Trematosaurus brauni forms the most common tetrapod in the Early Triassic of Germany, and is documented by numerous finds from Merkel’s Quarry at Bernburg (Saale). The revision of the available material includes 75 skulls with a size range between 10.9 and 41 cm skull length, and a small suite of postcranial element...

Paleopathology, the study of ancient disease, is a vital way by which we understand the evolution of pathogens, immune systems, healing physiology, and ultimately the environment. Cancer research has focused on its prevalence in various organisms and has found that although some animals have a high propensity for cancer,¹ others seem to be resistan...

The capitosaur Parotosuchus nasutus, exclusively known by historical finds from Merkel's Quarry at Bernburg (Saale), forms one of the most frequent tetrapods of the continental Triassic. A revision of the surviving material reveals a remarkable size range (14–44 cm skull length) of this large temnospondyl. P. nasutus is characterized by (1) quadrat...

The Pennsylvanian tetrapod Limnogyrinus elegans from the gas coal of Nyrany (Czech Republic) is revised. This small dissorophoid temnospondyl bears closer resemblance to the Permian genus Branchierpeton than hitherto known, highlighted by the abbreviated postparietal and tabular and the shallow squamosal embayment. It has a wide open squamosal emba...

Understanding the evolution of development is essential to unravel how morphological evolution proceeds in phenotypic space and how the resulting morphological disparity originates. In particular, the study of ontogenetic allometric patterns and their evolution is relevant because allometry is thought to constrain morphological evolution to specifi...

Continued excavations during the last decade have yielded large quantities of tetrapod remains from the Middle Triassic (Ladinian) Erfurt Formation (Lower Keuper) in Germany. The temnospondyl dental morphotypes are highly variable but represent low taxonomic diversity. This is in contrast to the reptilian tooth morphotypes, which comprise a minimum...

Although lepidosaurs are by far the most diverse and widespread group of present-day nonavian reptiles, with over 10,000 formally named species, their early diversification is documented only by a handful of incomplete fossils with few diagnostic features. Recent excavations in strata of the Lower Keuper (Middle Triassic: Ladinian) of Baden-Württem...

Miniaturization has been defined as the evolution of extremely small adult size in a lineage. It does not simply imply the decrease of the body size but also involves structural modifications to maintain functional efficiency at a strongly reduced size. Miniaturization has been proposed as a key factor in the origin of several major tetrapod clades...

The morphology of the Lower Permian genus Neldasaurus, a long-snouted dvinosaurian temnospondyl from the Texas Red Beds, is revised. The elongate skull is characterized by medially placed nares and a wide premaxilla-maxilla contact, and large vomerine fangs penetrating the mandible. A range of features is more consistent with other dvinosaurians th...

The SMNS houses one of the largest palaeontological collections in Europe. It includes 4.1 million fossils, many of which are types and originals to publications spanning more than three centuries of research. The collection has regional foci on Mesozoic invertebrates and reptiles, as well as Cenozoic mammals. It holds iconic specimens such as the...

The Lower Permian temnospondyl Edops craigi exemplifies an early and plesiomorphic condition of the single ear ossicle or stapes among the temnospondyls, the probable stem group of lissamphibians. In Edops, the 11‐cm‐long bone is more massive than in other temnospondyls, has a distinct neck, a dorsal crest and incompletely subdivided footplate and...

The bone tissue of femur, rib, and gastralia from three different individuals of the Middle Triassic pseudosuchian Batrachotomus kupferzellensis from southern Germany is studied. The femoral bone tissue comprises laminar fibrolamellar bone tissue throughout and is stratified by three annual growth cycles, indicating that the individual died early i...

Chroniosuchians form a mainly terrestrial or semi-terrestrial clade of Permian and Triassic crocodile- or varanid-like tetrapods, usually considered stem amniotes, but with disputed affinities within that grade. Two groups can be distinguished, the chroniosuchids and bystrowianids. Whereas the chroniosuchid skull and postcranium are well known, our...

The ears of extant amphibians are remarkably diverse and when fossil taxa are considered, the picture becomes even more complicated. Anurans have a differentiated stapes inside a middle ear cavity associated with a eustachian tube and tympanum. Instead, salamanders and caecilians have rudimentary stapes connected to the cheek or jaw articulation, a...

The Oligocene was a period of profound climatic and biotic changes, coinciding with a shift from a mostly ice-free warmhouse world at the Eocene-Oligocene boundary to a globally cooler, more seasonal climate. The Rauenberg locality (Baden-Württemberg, Germany) is one of the most significant early Oligocene fossil assemblages in Europe, containing b...

Fossils from the late Paleozoic continental Saar-Nahe Basin, SW Germany, have been known for more than 250 years. Though tetrapods are abundant and diverse, there is a significant lack of non-aquatic vertebrates from the study area. This gap in knowledge, however, is being filled by recent discoveries in probable 300 Ma (Gzhelian-Asselian) old fluv...

A juvenile turtle from the upper Kimmeridgian (Upper Jurassic) of Nusplingen is identified as an eurysternid turtle. It differs in plastral morphology from a juvenile eurysternid turtle from the latest Kimmerdigian of Kelheim described in the 19th century, which represents a comparably early developmental stage. Both juveniles have primordial ribs...

The lacustrine deposits of Vellberg, southern Germany, rank among the richest vertebrate fossil-lagerstätten of the Triassic worldwide. Continued excavation over one decade produced two chondrichthyans, 14 taxa of bony fishes, seven temnospondyls, one chroniosuchian, the stem-turtle Pappochelys, two procolophonians, four lepidosauromorphs, a choris...

The origin of turtles has been a persistent unresolved problem involving unsettled questions in embryology, morphology, and paleontology. New fossil taxa from the early Late Triassic of China (Odontochelys) and the Late Middle Triassic of Germany (Pappochelys) now add to the understanding of (i) the evolutionary origin of the turtle shell, (ii) the...

The large aetosaur Paratypothorax andressorum has so far been known only by its osteoderms. Here we describe for the first time the skull of a complete, articulated specimen of this taxon that was found in the type horizon at Murrhardt, southwestern Germany. Paratypothorax andressorum has the following cranial autapomorphies: (1) upper jaw margin w...

We report three isolated humeri of small-sized parareptiles, which represent two different taxa, from the lower Keuper (Erfurt Formation) of Germany. They constitute the first definitive evidence of parareptiles in the lower Keuper. The specimens represent the first records of an owenettid procolophonian (aff. Barasaurus ) from Europe and of a puta...

The invertebrates that have been used to define the Lettenkeuper Interval by KOZUR (1974a) in his biozonation scheme of the Germanic Middle Triassic are rather facies indicators than reliable biostratigraphic index fossils with determinable first and latest occurrences. This is also the case with the Lettenkeuper vertebrates and palynomorphs. The r...

The Lower Keuper is rich in temnospondyl amphibians, which are abundant in many horizons. Isolated fangs and vertebrae are common finds in lake and stream deposits. The largest known temnospondyl, Mastodonsaurus giganteus, was also the fi rst taxon of that group to be discovered, now known by numerous size classes. It is accompanied in some horizon...

The reptile fauna of the Lower Keuper has recently been studied in more detail, after a decade of excavation yielded rich finds from numerous aquatic and terrestrial groups. The marine or brackish reptiles encompass the sauropterygians Nothosaurus (4 species), Simosaurus, Neusticosaurus, and Psephosaurus. Only known by its vertebrae, the thalattosa...

This chapter aims at reconstructing Lower Keuper palaeocommunities in their habitats and to elucidate interdependences of plants, invertebrates, and vertebrates. Four major groups of palaeocommunities are differentiated: (1) The terrestrial palaeocommunities are poorly known from transported fl oral and faunal elements into submersed depositional e...

Since more than 100 years, the rich and well-preserved Lettenkeuper fl oras and faunas have induced scientists and inspired artists to compose reconstructions. These pictures shaped the imagination of laymen and scientists what Lower Keuper landscapes and their inhabitants might have been looking like. This article reproduces some of the most well...