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Skeletal remains of archosauriform reptiles from the Lower and lower Middle Triassic Buntsandstein Group in the Central European Basin are rare. This paper reports on a partial, almost completely disarticulated skeleton of a previously unknown archosauriform reptile from the lower Middle Triassic (Anisian) Röt Formation of Rotfelden in Baden-Württemberg (Germany). Marcianosuchus angustifrons gen. et sp. nov. is distinguished by the following combination of features: posterodorsal process of premaxilla slender, slightly inclined posterodorsally, and with rounded apex; posterodorsal surface of frontal covered by slightly diverging, fine longitudinal grooves; squamosal with distinct lateral ridge extending for entire length of element; teeth with proportionately small, weakly recurved crowns; humerus considerably shorter than femur; distal shaft of ischium rod-like, not plate-like; pubis with flat distal portion forming ‘pubic apron’: neural spines of posterior cervical and anterior dorsal vertebrae with transversely greatly expanded apices that are Y-shaped in anterior or posterior view; dorsal vertebrae with centra taller dorsoventrally than long anteroposteriorly; dorsal osteoderms more or less rectangular in outline, longer anteroposteriorly than wide mediolaterally, with slightly rounded anterior and concave posterior margins and bearing dorsal ridge or eminence; and dorsal surfaces of osteoderms with unsculptured anterior region and posterior region bearing keel or eminence and covered by sculpturing of radially arranged grooves and pits. Marcianosuchus angustifrons represents the first definitive record of a non-archosaurian archosauriform from the Buntsandstein Group of Germany. Its body plan most closely resembles that of Euparkeria capensis among well-known non-archosaurian archosauriform reptiles, but the two taxa are clearly distinct. [ABSTRACT FROM AUTHOR]

Here, we report a new small-bodied reptile taxon, Idiosaura virginiensis gen. et sp. nov., from the Upper Triassic (Carnian) Vinita Formation of the Richmond basin (Newark Supergroup) in east-central Virginia, U.S.A. The material consists of a fragmentary dentary bearing numerous tall cylindrical teeth implanted in a pleurodont fashion into spongy alveolar tissue. Micro-CT scan data reveal an unusual and complex network of interconnected neurovascular canals within the dentary with connections to the alveolar tissue and pulp cavities of the teeth. The external anatomy of the dentary is consistent with that of Triassic kuehneosaurid reptiles, suggesting affinities to that group; the results of a phylogenetic analysis were inconclusive but do not exclude kuehneosaurid relationships. Alongside the recently described Micromenodon pitti (Rhynchocephalia) and Vinitasaura lizae (Lepidosauromorpha), the new taxon adds to the relatively diverse assemblage of small-bodied reptiles known from the Tomahawk microvertebrate bonebed (USNM locality 39981). Relative tooth complexities of I. virginiensis and V. lizae were analyzed using the Orientation Patch Count Rotated method, and results suggest that the rise of lepidosauromorph ecomorphologies specializing for feeding on invertebrates occurred in Triassic communities alongside non-lepidosauromorph taxa with similar mandibulo-dental features, as in kuehneosaurs. [ABSTRACT FROM AUTHOR]

Most Triassic terrestrial diapsids belong to two clades, Lepidosauromorpha or (the more diverse) Archosauromorpha. Nevertheless, the phylogenetic relationships of some Triassic diapsids have remained uncertain for decades because of the lack of preservation of phylogenetically relevant anatomical regions or because of unusual combinations of features. One of these enigmatic forms is the small-sized Sphodrosaurus pennsylvanicus from the Upper Triassic Hammer Creek Formation of the Newark Supergroup in Pennsylvania (USA). It was first identified as a procolophonid parareptile, later as a probable rhynchosaur archosauromorph, and more recently as an indeterminate neodiapsid. Here we revise the anatomy of Sphodrosaurus pennsylvanicus in order to include it for the first time in a quantitative phylogenetic analysis, which is focused on Permo–Triassic neodiapsids. Sphodrosaurus pennsylvanicus is recovered in this analysis as a doswelliid proterochampsian within Archosauromorpha. As a result, this taxon is added to the list of doswelliids known from the Carnian–Norian of the eastern and south-western USA. Previous authors recognized that the most unusual feature of Sphodrosaurus pennsylvanicus is its proportionally very large skull. Phylogenetic generalized least squares regressions confirmed that Sphodrosaurus pennsylvanicus has a larger skull than the vast majority of Permo–Triassic diapsids. Optimization in the phylogeny of the skull width to presacral length ratio shows the most likely scenario is that the extremely broad skull of Sphodrosaurus pennsylvanicus is autapomorphic, but it is not unique among archosauromorphs, being paralleled by hyperodapedontine rhynchosaurs and the proterochampsian Proterochampsa barrionuevoi. Exploration of a morphospace of linear measurements shows that Sphodrosaurus pennsylvanicus shares strong similarities with the probably semi-aquatic Proterochampsa barrionuevoi, suggesting that the former species may have had a similar mode of life. A linear discriminant analysis of ungual functional categories found that the only preserved ungual of Sphodrosaurus pennsylvanicus was suitable for digging or some other way of substrate processing. [ABSTRACT FROM AUTHOR]

A new alvarezsaurid theropod, Dzharaonyx eski, gen. et sp. nov., is documented by a variety of dissociated but well-preserved postcranial bones from the Upper Cretaceous (Turonian) Bissekty Formation at Dzharakuduk, Uzbekistan. It has opisthocoelous posterior dorsal vertebrae lacking infrapostzygapophyseal fossae. The posterior caudal vertebrae are procoelous and have a longitudinal canal within the neural arch. The humerus is intermediate in structure between those of the Argentinian alvarezsaurid Patagonykus and the Mongolian parvicursorine Mononykus in having a small internal tuberosity, similar-sized radial and ulnar condyles, a distally protruding radial condyle, and a greatly reduced entepicondyle. The ulna has a hypertrophied olecranon process, a globular carpal trochlea, and a facet for the aponeurosis tubercle of the radius. On the carpometacarpus, the articular surface of metacarpal III is in line with the distal articular joint of metacarpal II. On manual phalanx II-1, the flexor ridges are similarly developed and the dorsolateral process and the 'hook-like' ventrolateral process are absent. The collateral grooves on manual ungual phalanx II-2 are either partially open or completely enclosed to form ventral foramina. The pubis bears a preacetabular tubercle. The pes is arctometatarsalian. Metatarsal II forms a posterolateral flange. Pedal phalanx IV-1 has a protruding proximomedial process, a proximoventral notch, and asymmetrical distal condyles. The flexor tubercles on the pedal ungual phalanges are small. Phylogenetic analysis found Dzharaonyx within Parvicursorinae in a polytomy with other Asiatic taxa. Dzharaonyx is the most plesiomorphic and geologically oldest member of Parvicursorinae known to date. [ABSTRACT FROM AUTHOR]

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 overlying Evangeline Member of the Wolfville Formation. Although dissociated and fragmentary, the skeletal elements document the presence of a lonchorhynchine trematosaurid and at least two taxa of capitosauroid temnospondyls, procolophonid parareptiles, several taxa of archosauromorph reptiles, and a kannemeyeriiform dicynodont synapsid. Particularly noteworthy is the first definite record of the long-necked archosauromorph Tanystropheus from eastern North America. The strata of the Economy Member were deposited in a semiarid setting but the presence of various temnospondyls indicates the existence of perennial bodies of water. The age of this unit has long been regarded as Middle Triassic (Anisian to Ladinian) based on the tetrapod record, and the present study supports this assessment. The tetrapod assemblage most closely resembles those from the upper Moenkopi Formation of the American Southwest and the upper Middle to Upper Buntsandstein of Germany. The Economy Member is the oldest known Triassic tetrapod-bearing stratigraphic unit as well as the first occurrence of Middle Triassic continental tetrapods in eastern North America. [ABSTRACT FROM AUTHOR]

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 this interval. Here we present an interesting record of a reptile with an unusual dentition. The material comprises a fragment of a left dentary. The teeth are tightly spaced and have chisel-shaped crowns, with the posterolingually extending apices abutting those of the successive teeth and forming a continuous cutting edge. Micro-computed tomography scanning of the jaw fragment revealed the teeth have expanded roots and sit on an open, shallow groove. The Meckelian canal is partially open lingually and a second canal for the inferior alveolar nerve and artery extends parallel to it. Although the preserved anatomical features of the material are insufficient for precise phylogenetic placement, the structure of the robust dentary and its teeth resembles those of some lepidosaurs and certain early Mesozoic marine diapsids. The distinctive morphology of the teeth, combined with the apparent lack of tooth wear, makes it difficult to assess their functional significance. It is interesting that extinct tetrapods with similar tooth morphologies come from strata representing freshwater and brackish-water paleoenvironments, which may serve as an additional line of evidence for future Morpho-functional assessments. [ABSTRACT FROM AUTHOR]

We describe a new taxon of lepidosauromorph reptile, Vinitasaura lizae, based on a nearly complete dentary and the posterior portion of a second dentary from the Upper Triassic (upper Carnian) Vinita Formation in east-central Virginia. It offers new insights into the morphological diversification and spatiotemporal distribution of lepidosauromorphs during the Triassic. The lepidosauromorph assemblage from the Vinita Formation include at least two other taxa and reveals connections to others in Europe and North America. It currently provides the best record of the early diversification of these reptiles in equatorial Pangaea, highlighting the potential importance of similar assemblages from still poorly sampled regions such as western North America for addressing questions concerning the origin and evolutionary history of this major diapsid clade during the Triassic. [ABSTRACT FROM AUTHOR]

This paper provides a description and analysis of cranial remains of a rhynchosaur from the Upper Triassic Evangeline Member of the Wolfville Formation of Nova Scotia, Canada. This material, primarily comprising jaw elements, represents the first definitive record of Late Triassic rhynchosaurs from eastern North America. All cranial bones can be assigned to Hyperodapedontinae. The dentition of the Nova Scotian hyperodapedontine differs from those of Hyperodapedon and Isalorhynchus. The maxilla apparently did not have more than two lateral rows and two medial rows of teeth. The teeth of the lateral row closest to the single groove dividing the maxillary tooth plate are more than twice as large as those of the medial row closest to the groove. The lateral and medial tooth-bearing portions of the maxilla become increasingly crest-like during ontogeny. The dentary lacks a lingual row of teeth. Based on this combination of features, the hyperodapedontine material from the Evangeline Member is assigned to a new taxon, Oryctorhynchus bairdi, gen. et sp. nov., which is the sister species to an unnamed hyperodapedontine taxon from Wyoming. This clade was recovered as the sister taxon to Hyperodapedon spp. in the phylogenetic analysis. The late Carnian or earliest Norian tetrapod assemblage from the Evangeline Member represents a mixture of faunal elements from a wide paleolatitudinal range, suggesting a more cosmopolitan distribution for continental tetrapods during the early Late Triassic than previously assumed. [ABSTRACT FROM AUTHOR]

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 craniodental autapomorphies, including mesial and distal carinae of labiolingually flattened maxillary and dentary tooth crowns with large, somewhat hook-shaped denticles aligned at distinct angle to apicobasal axis of tooth crown; premaxilla with long, leaf-shaped posterodorsal process that is slightly longer than body of element; presence of prominent lateral fossa on premaxilla anteroventral to external narial fenestra; premaxilla with five gently recurved, conical teeth; medial surface of maxilla with distinct ledge above the interdental plates; and maxilla and dentary with distinctly heterodont dentition. Phylogenetic analysis recovered Polymorphodon adorfi in a position crownward of Erythrosuchus africanus but in an unresolved polytomy with derived non-archosaurian archosauriforms such as Proterochampsidae and Euparkeria capensis and with Archosauria. The maxillary and dentary teeth of Polymorphodon adorfi differ from those of other non-archosaurian archosauriforms and indicate a different, possibly omnivorous diet, suggesting that these reptiles were more diverse in terms of feeding habits than previously assumed. [ABSTRACT FROM AUTHOR]

Teraterpeton hrynewichorum is an unusual archosauromorph reptile from the Upper Triassic (Carnian) Evangeline Member of the Wolfville Formation in Nova Scotia (Canada). Its long snout has transversely broad, cusped 'molariform' teeth posteriorly and lacks teeth anteriorly. The temporal region of the cranium is 'euryapsid' with large upper and closed lower temporal fenestrae. A previously undescribed specimen referable to Teraterpeton includes a nearly complete pelvic girdle and both hind limbs. The ilium has a long, dorsoventrally deep anterior process similar to that of derived rhynchosaurs. The pelvis has a well-developed thyroid fenestra, a feature shared only by Tanystropheidae among Archosauromorpha. Metatarsal V is proximodistally short, resembling the condition in Tanystropheidae. The pedal unguals of Teraterpeton are strongly flattened mediolaterally, dorsoventrally deep and weakly curved, much like the manual unguals. We performed a phylogenetic analysis of a matrix comprising 61 taxa of Permo-Triassic diapsid reptiles and 337 characters, which supports the position of Teraterpeton as the sister-taxon of Trilophosaurus + Spinosuchus. In the current phylogeny, parsimony-based character optimization of the aforementioned character-states in Teraterpeton indicate that all were acquired independently from other saurian lineages. The unusual combination of postcranial features in Teraterpeton underscores the critical importance of comprehensive taxon sampling for understanding the mode of character change among Triassic diapsid reptiles and careful apomorphy-based identifications to faunal analyses. [ABSTRACT FROM AUTHOR]

An isolated dorsal osteoderm of a chroniosuchian from a late Permian fissure filling in the lower Zechstein (Z1) of central Germany represents the first Permian-age record of this enigmatic tetrapod clade outside Russia and China. Based on a number of features, the specimen is designated the holotype of a new taxon, Hassiacoscutum munki, and referred to the chroniosuchian clade Bystrowianidae. Phylogenetic analysis based on a recently published data set with addition of Hassiacoscutum and other recently described bystrowianids (Yumenerpeton, Jiyuanitectum, and Vyushkoviana) found good support for the clade Chroniosuchia and its subclades Chroniosuchidae and Bystrowianidae, but with little internal resolution for the latter. A second phylogenetic analysis of all known bystrowianid genera based solely on osteoderm characters yielded a well-supported and well-resolved clade Bystrowianidae with two subclades: (Yumenerpeton + (Synesuchus + Bystrowiella)) and (Jiyuanitectum + (Bystrowiana + (Hassiacoscutum + (Vyushkoviana + (Dromotectum + Axitectum))))). Hassiacoscutum provides a paleobiogeographic link to other middle and late Permian assemblages of Laurasian continental tetrapods. To date, chroniosuchians are known only from Laurasia, and their apparent absence in Gondwana hints at faunal provincialism across Pangaea. [ABSTRACT FROM AUTHOR]

Richardoestesia is an enigmatic theropod dinosaur originally described on the basis of a pair of dentaries (holotype of R. gilmorei Currie et al., 1990) and isolated distinctive teeth, which are abundant in the Upper Cretaceous of North America. Richardoestesia asiatica (Nesov, 1995) is represented by numerous isolated teeth from the Upper Cretaceous Khodzhakul, Bissekty, and Aitym formations of Uzbekistan. Richardoestesia asiatica shows the typical features of the genus, including small mesial and distal denticles (on average 28.4 and 34.5 denticles per 5 mm, respectively), rectangular or knob-like denticles, and an apically convex distal margin of the tooth crown. The sample of R. asiatica has a large proportion of straight teeth (morphotype A) and includes several types of recurved teeth related to their position in the jaws (morphotypes B–E). This species differs from R. gilmorei in the presence of straight teeth and fully serrated mesial carinae. Richardoestesia asiatica cannot be distinguished from R. isosceles Sankey, 2001, which we consider a nomen dubium due, in part, to the imperfect nature of its holotype. Discriminant function analysis (DFA) of dental measurements found no distinction between the samples from Khodzhakul and Bissekty formations. In DFA including North American samples, the morphospace of R. asiatica completely overlaps that of the sample from the Lance Formation (Maastrichtian) of Wyoming and only partly overlaps with that of the sample from the Milk River Formation (Santonian) of Alberta. [ABSTRACT FROM AUTHOR]

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 and limbs. At the same time, it is more plesiomorphic in retaining a fully diapsid skull and in lacking both neurals and a plastron with plate-like elements. Pappochelys provides important new evidence that the carapace and plastron of turtles are distinct moieties that evolved independently from each other. The skull of Pappochelys is more or less triangular in plan view. The marginal dentition comprises peg-like teeth with subthecodont implantation. Whereas the upper temporal fenestra is relatively small and rounded, the lower temporal opening is large and ventrally open. The slender vomers are fused. The vertebral column of Pappochelys comprises probably eight cervical, probably nine dorsal, two sacral, and more than 24 caudal vertebrae. The dorsal ribs have asymmetrical anterior and posterior flanges and their external surfaces are heavily ornamented. The gastralia form pairs of robust elements, one per vertebral segment. The scapula has a slender dorsal shaft and a rounded ‘acromial’ flange. The humerus has a slightly dorsally raised proximal head and a gently sigmoidal curvature. The pubis closely resembles that of Odontochelys in overall shape and has a well-developed lateral process. We performed a phylogenetic analysis using a modified character-taxon matrix (272 characters, 50 taxa) from a recent study to assess the placement of Pappochelys among amniotes. Pappochelys was found to nest among Pantestudines with Eunotosaurus and the more derived Odontochelys and Proganochelys. The diapsid affinities of turtles are well supported but it is still unresolved whether turtles are saurians or only related to the latter. [ABSTRACT FROM AUTHOR]

An ornithomimid theropod dinosaur from the Upper Cretaceous (Turonian) Bissekty Formation of Uzbekistan is one of the basal members of Ornithomimidae. Here we present a description of ontogenetic changes in the long-bone histology of this taxon and distinguish four distinct histological stages. Analysis of a growth series of femora demonstrates early histological maturation during ontogeny in the Bissekty ornithomimid, expressed by the progressive formation of Haversian bone, endosteal bone deposition, and changing of composition of primary bone tissue from fibrolamellar complex to parallel-fibered bone with only a small amount of woven bone. The long-bone histology of the Bissekty ornithomimid is similar to that of the basal ornithomimidArchaeornithomimus asiaticusand differs from those of derived ornithomimids in early histological maturation, the absence of laminar and plexiform vascularization of the primary cortex, and the presence of little or no woven bone in medium-sized and large individuals. These differences could reflect size-related evolutionary transformation of the bone histology during the transition from basal to derived ornithomimids. The discovery of apparent medullary bone in a mid-sized femur suggests that the females of the Bissekty ornithomimid were sexually mature at least after attaining 75% of maximum size. [ABSTRACT FROM AUTHOR]

The isolated adult teeth of titanosaurian sauropods from the Upper Cretaceous Bissekty Formation at Dzharakuduk, Uzbekistan, differ little in overall structure but show considerable variation in enamel sculpturing and wear patterns. The crown shape of unworn juvenile teeth ranges from lanceolate to conical. Most specimens have enamel texture resembling crumpled paper or completely smooth enamel. Longitudinal grooves along the mesial and distal edges are present on only a few tooth crowns and might be developed on both the labial and lingual sides. Among 252 worn tooth crowns there are eight variants of wear patterns, all possible combinations of 0–2 apical and 0–2 lateral wear facets. The most common is wear pattern A1L0 (one apical facet, no lateral facets; 62.7%). The next most common variant has two apical and no lateral facets (A2L0, 12.3%). These apical wear facets include the primary wear facets, which are produced by an opposing functional tooth, and secondary wear facets, which are produced by a replacing upper tooth coming into contact with the functional lower tooth at a late wear stage. The relative abundance of tooth crowns with two apical wear facets possibly suggests incipient development of a tooth battery in the Bissekty titanosaur. [ABSTRACT FROM PUBLISHER]

Exposures of the Bissekty Formation (Upper Cretaceous: middle-upper Turonian) at Dzharakuduk in the central Kyzylkum Desert of Uzbekistan have yielded abundant dinosaurian remains. We report here on cranial and postcranial remains that can be attributed to titanosaurian sauropods. This material is of considerable interest in view of the relative scarcity of sauropod fossils from the Upper Cretaceous of Central Asia. An incomplete braincase originally assigned to the ceratopsian Turanoceratops tardabilis actually belongs to a derived titanosaurian. It shares a number of features (including broad basal tubera and presence of wide depression between basal tubera) with braincases of various derived titanosaurian taxa from Asia and South America. Computed tomographic (CT) scanning of the braincase permitted digital reconstruction of a partial endocast. Overall, this endocast resembles those of other sauropods, although the pituitary fossa is considerably swollen. As in other derived titanosaurians, the abducens nerve passed lateral to the pituitary fossa. The inner ear resembles that of some other titanosaurs in having a very short lateral semicircular canal and that the anterior semicircular canal is only slightly longer than the posterior one. Isolated sauropod teeth from Dzharakuduk have slender, 'pencil-shaped' crowns, which often bear high-angle apical wear facets. The caudal vertebrae are gently opisthocoelous rather than procoelous, as is typically the condition on at least the anterior caudals in many other titanosaurs. An anterior caudal vertebra shows extensive pneumatization of its neural arch. The sauropod remains from the Bissekty Formation establish the presence of titanosaurians in Central Asia during the Turonian. [ABSTRACT FROM AUTHOR]

Numerous well-preserved skeletal remains of a distinctive armoured archosauriform reptile from the Lower Keuper (Erfurt Formation; Middle Triassic: Ladinian: Longobardian) of Baden-Württemberg (Germany) represent a new taxon,Jaxtasuchus salomonigen. et sp. nov. The dermal armour ofJaxtasuchuscomprises transverse rows of four rectangular osteoderms each in the cervical, dorsal and caudal regions, with the individual plates closely resembling those ofDoswellia kaltenbachifrom Carnian strata in North America. The long and low maxilla ofJaxtasuchusheld at least 15 teeth. The labial and lingual surfaces of the tall, only slightly recurved crowns of the maxillary teeth bear distinct vertical ridges and smooth mesial and distal carinae. The cervical region of the vertebral column is long. Phylogenetic analysis placesJaxtasuchusas the sister taxon toDoswelliain DoswelliidaesensuDesojoet al. (2011). Doswelliidae is diagnosed by the coarsely reticulate, incised ornamentation of osteoderms composed of central regular pits of subequal size and contour, and a mostly smooth anterior articular lamina on each osteoderm. The discovery ofJaxtasuchusconfirms that Doswelliidae had a wide palaeogeographical distribution during the latter half of the Triassic. http://www.zoobank.org/urn:lsid:zoobank.org:pub:4A400628-07F3-4D1B-9CA8-336C379721FA [ABSTRACT FROM PUBLISHER]

The holotype of the large temnospondylCalamops paludosusis the oldest known tetrapod fossil from the Triassic of the Newark basin in Pennsylvania. Although it is usually placed in Metoposauridae, its affinities have remained unknown since its original description because the unique specimen had never been prepared. Preparation and casting of the specimen, which comprises three pieces of a left mandibular ramus, now permits detailed anatomical description of the jaw and assessment of its affinities.Calamops paludosusis a valid taxon of trematosauroid temnospondyls that can be diagnosed by several autapomorphies. It represents one of the geologically youngest known records of long-snouted trematosaurs and the first record of these temnospondyls from the Late Triassic of North America. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free atwww.tandfonline.com/UJVP [ABSTRACT FROM PUBLISHER]

The article discusses the discovery of Colognathus fossils in strata of the the Lower Keuper near Vellberg in Baden-Württemberg, Germany. It mentions the presence of an edentulous region anterior of the two large posterior teeth of the Vellberg specimens. It differentiates the crown structure details, such as crown surfaces shapes and the labiolingual fluting in the apical region, of the discovered fossils from Vellberg and the holotype of Colognathus obscurus. It states that the German specimens was identified as Colognathus sp. based on the difference in the occlusal outline of the posterior tooth and greater stratigraphic age.

Two embryonic skeletons preserved inside thin-shelled eggs of a partially preserved clutch from the Upper Elliot Formation (Lower Jurassic) of South Africa have been attributed to the sauropodomorph dinosaur Massospondylus carinatus. A virtually complete skeleton is exposed in right lateral view, with the slightly telescoped skull and several cervical vertebrae extending beyond the eggshell. A second, partial skeleton has a skull preserved in dorsal view. The embryos have proportionately very large skulls, with the broad skull table formed by wide parietals and frontals. The wide posterolateral wing of the frontal separates the postorbital from contact with the parietal. The embryos have short rather than elongated cervical vertebrae, with tall rather than low neural arches. The large forelimbs are only slightly shorter than the hind limbs, which suggests an obligatory quadrupedal posture for the hatchlings. This pattern may represent an ontogenetic constraint related to the large size of the head and horizontally oriented neck. Similarities between the embryonic and post-hatchling specimens include the slenderness of the lower jaw and slight ventral curvature of the symphyseal portion of the dentary, the large supraorbital process of the prefrontal, and the tall antorbital and infratemporal fenestrae. There are 10 cervical, 14 dorsal, and three sacral vertebrae. The large distal claw-bearing phalanx of manual digit 1 is longer than any other phalangeal element of either manus or pes. The embryos of Massospondylus carinatus represent the oldest dinosaurian embryos known to date. [ABSTRACT FROM AUTHOR]

We present a detailed account on the skeletal structure of the traversodont cynodont Boreogomphodon jeffersoni on the basis of a considerable quantity of excellently preserved craniodental remains and several referred postcranial bones from the Tomahawk Creek Member of the Vinita Formation (Upper Triassic: Carnian) of the Richmond basin (Newark Supergroup) in eastern Virginia. The small size, proportionately short snout and mandible, low number of molariform postcanine teeth, and presence of up to three sectorial postcanines all indicate that most of the specimens recovered to date represent immature individuals. The superbly preserved dental material permits detailed inferences regarding tooth replacement and dental function during ontogeny. Boreogomphodon differs from other known traversodont cynodonts primarily in the possession of lower molariform postcanine teeth with three rather than two anterior cusps in all but the smallest specimens, zygomatic arches that are bowed laterally at about mid-length, and pronounced, irregular sculpturing on the dorsal surface of the snout. Plesiomorphic features of traversodont cynodonts retained by Boreogomphodon include the position of the paracanine fossa anterolingual to the upper canine as well as the presence of a distinct central cusp and a posterior cingulum on the upper molariform postcanines. Phylogenetic analysis suggests the existence of a clade comprising Boreogomphodon plus two other taxa (Arctotraversodon and Nanogomphodon) in the Northern Hemisphere that is the sister group to most other known Middle and Late Triassic traversodonts from Gondwana. [ABSTRACT FROM AUTHOR]

The article presents a detailed redescription of the Late Triassic archosauromorph reptile Doswellia kaltenbachi from the Poor Farm Member of the Falling Creek Formation in the Taylorsville basin in Virginia. It also presents a new phylogenetic analysis to assess the phylogenetic position of Doswellia among basal archosauriforms and to test the current hypotheses of archosauriform interrelationships. The phylogenetic analysis presented incorporates new data of Doswellia and the taxa Turfanosuchus, Yonghesuchus and Quinosuchus that have not previously been combined in a single study.

Highlights from the article: Although now widely used in the paleontological literature, the name Tetrapoda has a surprisingly complex history and its first use as a formal taxonomic name has apparently never been clarified. Benton's textbook on vertebrate paleontology lists a "Superclass Tetrapoda" comprising Amphibia and Amniota as well as a number of extinct taxa (Benton, [1]:326, [2]:436). In the former publication, he designated Tetrapoda as an "Unterstamm" (subphylum) of Vertebrata to include Amphibia, Reptilia, Aves, and Mammalia, as well as various extinct groups (Jaekel, [23]:200). This raises the issue of whether the use of the nomen Tetrapoda as a homonym for higher taxa in Squamata, Lepidoptera, and Vertebrata is acceptable.

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-Württemberg, Germany, have yielded abundant skeletal remains of a diversity of small- to medium-sized diapsid reptiles, which include at least three taxa of lepidosauromorphs. One, here named Fraxinisaura rozynekae, is a small-bodied reptile characterized by (1) maxillary and dentary tooth crowns conical, with lingual striae near their apices; (2) maxilla with a dorsoventrally low facial process and long tooth-bearing portion anterior to this process; (3) jugal with a short anterior process and a very short, pointed posterior process; and (4) ilium with a tall, posterodorsally extending blade. Tooth implantation is pleurodont. Size variation in the sample sheds some light on ontogenetic changes, mainly affecting the shape of and ornamentation on cranial bones. Phylogenetic analysis recovered Fraxinisaura rozynekae among Lepidosauromorpha and as the sister taxon of the Middle to Late Jurassic Marmoretta oxoniensis. Unfortunately, currently existing character-taxon matrices do not allow confident resolution of the interrelationships of these and other early Mesozoic lepidosauromorph reptiles. http://zoobank.org/urn:lsid:zoobank.org:pub:02C69A1C-FCC8-4D0C-BA71-79BA30BC9DA7 SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Citation for this article: Schoch, R. R., and H.-D. Sues. 2018. A new lepidosauromorph reptile from the Middle Triassic (Ladinian) of Germany and its phylogenetic relationships. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2018.1444619. [ABSTRACT FROM AUTHOR]

Citation for this article: Scheyer, T. M., and H.-D. Sues. 2016. Expanded dorsal ribs in the Late Triassic pseudosuchian reptileEuscolosuchus olseni. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1248768. [ABSTRACT FROM AUTHOR]