Showing posts with label Early Triassic. Show all posts
Showing posts with label Early Triassic. Show all posts
Platypus-like Hupehsuchian from Early Triassic of China
Cheng, L., Motani, R., Jiang, D., Yan, C., Tintori, A. and O. Rieppel. 2019. Early Triassic marine reptile representing the oldest record of unusually small eyes in reptiles indicating non-visual prey detection. Scientific Reports 9, number 152. DOI: 10.1038/s41598-018-37754-6
Abstract - The end-Permian mass extinction (EPME) led to reorganization of marine predatory communities, through introduction of air-breathing top predators, such as marine reptiles. We report two new specimens of one such marine reptile, Eretmorhipis carrolldongi, from the Lower Triassic of Hubei, China, revealing superficial convergence with the modern duckbilled platypus (Ornithorhynchus anatinus), a monotreme mammal. Apparent similarities include exceptionally small eyes relative to the body, snout ending with crura with a large internasal space, housing a bone reminiscent of os paradoxum, a mysterious bone of platypus, and external grooves along the crura. The specimens also have a rigid body with triangular bony blades protruding from the back. The small eyes likely played reduced roles during foraging in this animal, as with extant amniotes (group containing mammals and reptiles) with similarly small eyes. Mechanoreceptors on the bill of the animal were probably used for prey detection instead. The specimens represent the oldest record of amniotes with extremely reduced visual capacity, utilizing non-visual cues for prey detection. The discovery reveals that the ecological diversity of marine predators was already high in the late Early Triassic, and challenges the traditional view that the ecological diversification of marine reptiles was delayed following the EPME.
New Specimen of Prolacerta broomi from the Early Triassic of Antarctica
Spiekman, S. N. F. 2018. A new specimen of Prolacerta broomi from the lower Fremouw Formation (Early Triassic) of Antarctica, its biogeographical implications and a taxonomic revision. Scientific Reports 8, Article number: 17996. https://www.nature.com/ articles/s41598-018-36499-6
Abstract - Prolacerta broomi is an Early Triassic archosauromorph of particular importance to the early evolution of archosaurs. It is well known from many specimens from South Africa and a few relatively small specimens from Antarctica. Here, a new articulated specimen from the Fremouw Formation of Antarctica is described in detail. It represents the largest specimen of Prolacerta described to date with a nearly fully articulated and complete postcranium in addition to four skull elements. The study of this specimen and the re-evaluation of other Prolacerta specimens from both Antarctica and South Africa reveal several important new insights into its morphology, most notably regarding the premaxilla, manus, and pelvic girdle. Although well-preserved skull material from Antarctica is still lacking for Prolacerta, a detailed comparison of Prolacerta specimens from Antarctica and South Africa corroborates previous findings that there are no characters clearly distinguishing the specimens from these different regions and therefore the Antarctic material is assigned to Prolacerta broomi. The biogeographical implications of these new findings are discussed. Finally, some osteological characters for Prolacerta are revised and an updated diagnosis and phylogenetic analysis are provided.
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UWBM 95529 |
Paleoecology of the Early Triassic Dinwoody Formation: Insights on Recovery After the End-Permain Extinction
Hofmann, R., Hautmann, M. and H. Bucher. 2013. A New Paleoecological Look at the Dinwoody Formation (Lower Triassic, Western USA): Intrinsic Versus Extrinsic Controls on Ecosystem Recovery After the End-Permian Mass Extinction Journal of Paleontology 87:854-880. 2013 doi: http://dx.doi.org/10.1666/12-153
Abstract - The Dinwoody Formation of the western United States represents an important archive of Early Triassic ecosystems in the immediate aftermath of the end-Permian mass extinction. We present a systematic description and a quantitative paleoecological analysis of its benthic faunas in order to reconstruct benthic associations and to explore the temporal and spatial variations of diversity, ecological structure and taxonomic composition throughout the earliest Triassic of the western United States. A total of 15 bivalve species, two gastropod species, and two brachiopod species are recognized in the study area. The paleoecological analysis shows that the oldest Dinwoody communities are characterized by low diversity, low ecological complexity and high dominance of few species. We suggest that this low diversity most likely reflects the consequences of the mass extinction in the first place and not necessarily the persistence of environmental stress. Whereas this diversity pattern persists into younger strata of the Dinwoody Formation in outer shelf environments, an increase in richness, evenness and guild diversity occurred around the Griesbachian–Dienerian boundary in more shallow marine habitats. This incipient recovery towards the end of the Griesbachian is in accordance with observations from other regions and thus probably represents an interregional signal. In contrast to increasing richness within communities (alpha-diversity), beta-diversity remained low during the Griesbachian and Dienerian in the study area. This low beta-diversity reflects a wide environmental and geographical range of taxa during the earliest Triassic, indicating that the increase of within-habitat diversity has not yet led to significant competitive exclusion. We hypothesize that the well-known prevalence of generalized taxa in post-extinction faunas is primarily an effect of reduced competition that allows species to exist through the full range of their fundamental niches, rather than being caused by unusual and uniform environmental stress.
Abstract - The Dinwoody Formation of the western United States represents an important archive of Early Triassic ecosystems in the immediate aftermath of the end-Permian mass extinction. We present a systematic description and a quantitative paleoecological analysis of its benthic faunas in order to reconstruct benthic associations and to explore the temporal and spatial variations of diversity, ecological structure and taxonomic composition throughout the earliest Triassic of the western United States. A total of 15 bivalve species, two gastropod species, and two brachiopod species are recognized in the study area. The paleoecological analysis shows that the oldest Dinwoody communities are characterized by low diversity, low ecological complexity and high dominance of few species. We suggest that this low diversity most likely reflects the consequences of the mass extinction in the first place and not necessarily the persistence of environmental stress. Whereas this diversity pattern persists into younger strata of the Dinwoody Formation in outer shelf environments, an increase in richness, evenness and guild diversity occurred around the Griesbachian–Dienerian boundary in more shallow marine habitats. This incipient recovery towards the end of the Griesbachian is in accordance with observations from other regions and thus probably represents an interregional signal. In contrast to increasing richness within communities (alpha-diversity), beta-diversity remained low during the Griesbachian and Dienerian in the study area. This low beta-diversity reflects a wide environmental and geographical range of taxa during the earliest Triassic, indicating that the increase of within-habitat diversity has not yet led to significant competitive exclusion. We hypothesize that the well-known prevalence of generalized taxa in post-extinction faunas is primarily an effect of reduced competition that allows species to exist through the full range of their fundamental niches, rather than being caused by unusual and uniform environmental stress.
An Absolutely Beautiful (and Incredible) Fossil from the Early Triassic of South Africa
Fernandez, V., Abdala, F., Carlson, K.J., Cook, D.C., Rubidge, B.S., Yates, A., and P. Tafforeau. 2013. Synchrotron Reveals Early Triassic Odd Couple: Injured Amphibian and Aestivating Therapsid Share Burrow. PLoS ONE 8(6): e64978. doi:10.1371/journal.pone.0064978.
Abstract - Fossorialism is a beneficial adaptation for brooding, predator avoidance and protection from extreme climate. The abundance of fossilised burrow casts from the Early Triassic of southern Africa is viewed as a behavioural response by many tetrapods to the harsh conditions following the Permo-Triassic mass-extinction event. However, scarcity of vertebrate remains associated with these burrows leaves many ecological questions unanswered. Synchrotron scanning of a lithified burrow cast from the Early Triassic of the Karoo unveiled a unique mixed-species association: an injured temnospondyl amphibian (Broomistega) that sheltered in a burrow occupied by an aestivating therapsid (Thrinaxodon). The discovery of this rare rhinesuchid represents the first occurrence in the fossil record of a temnospondyl in a burrow. The amphibian skeleton shows signs of a crushing trauma with partially healed fractures on several consecutive ribs. The presence of a relatively large intruder in what is interpreted to be aThrinaxodon burrow implies that the therapsid tolerated the amphibian’s presence. Among possible explanations for such unlikely cohabitation, Thrinaxodon aestivation is most plausible, an interpretation supported by the numerous Thrinaxodon specimens fossilised in curled-up postures. Recent advances in synchrotron imaging have enabled visualization of the contents of burrow casts, thus providing a novel tool to elucidate not only anatomy but also ecology and biology of ancient tetrapods.
Abstract - Fossorialism is a beneficial adaptation for brooding, predator avoidance and protection from extreme climate. The abundance of fossilised burrow casts from the Early Triassic of southern Africa is viewed as a behavioural response by many tetrapods to the harsh conditions following the Permo-Triassic mass-extinction event. However, scarcity of vertebrate remains associated with these burrows leaves many ecological questions unanswered. Synchrotron scanning of a lithified burrow cast from the Early Triassic of the Karoo unveiled a unique mixed-species association: an injured temnospondyl amphibian (Broomistega) that sheltered in a burrow occupied by an aestivating therapsid (Thrinaxodon). The discovery of this rare rhinesuchid represents the first occurrence in the fossil record of a temnospondyl in a burrow. The amphibian skeleton shows signs of a crushing trauma with partially healed fractures on several consecutive ribs. The presence of a relatively large intruder in what is interpreted to be aThrinaxodon burrow implies that the therapsid tolerated the amphibian’s presence. Among possible explanations for such unlikely cohabitation, Thrinaxodon aestivation is most plausible, an interpretation supported by the numerous Thrinaxodon specimens fossilised in curled-up postures. Recent advances in synchrotron imaging have enabled visualization of the contents of burrow casts, thus providing a novel tool to elucidate not only anatomy but also ecology and biology of ancient tetrapods.
Early Triassic Ichnoassemblages of Wyoming
This new paper suggests the presence of dinosauromorph (cf. Rotodactylus) and turtle-like (cf. Chelonipus) trackmakers from the Lower Triassic of Wyoming.
Lovelace, D. M., and S. D. Lovelace. 2012. Paleoenvironments and paleoecology of a Lower Triassic invertebrate and vertebrate ichnoassemblage from the Red Peak Formation (Chugwater Group), central Wyoming. Palaios 27:636-657. doi: 10.2110/palo.2012.p12-011r
Abstract - The Lower Triassic Red Peak Formation of the Chugwater Group has long been considered to have an extremely poor paleontological record, although the cause for the apparent dearth of fossils has yet to be been determined. During the course of fieldwork in central Wyoming numerous vertebrate and invertebrate ichnogenera (n ≥ 11) were observed. Vertebrate tracks and trackways representative of dinosauromorph, archosaur, lepidosaur, and testudinate trackmakers were found (cf. Rotodactylus, Chirotherium barthii, Rhynchosauroides, and cf. Chelonipus respectively). An invertebrate ichnoassemblage composed of at least 6 ichnogenera consistent with the Scoyenia ichnofacies were also found (e.g., Diplichnites, Lockeia, Fuersichnus communis, Palaeophycus striatus, cf. Scoyenia, and cf. Scolicia). The majority of these tracks and traces were found in the upper platy facies (upper 10–20 m of the Red Peak Formation), which is thought to be no younger than upper Spathian in age. Sedimentary structures, architectural elements, and lateral stratigraphic relationships support the interpretation of floodplain, fluvial, and lacustrine deposition for the upper platy facies in central Wyoming. The Red Peak Formation vertebrate and invertebrate ichnoassemblages, along with their associated depositional environments, are consistent with a fluviolacustrine (continental) setting comparable to those described from Lower to Middle Triassic strata with a Pangean distribution, including the Moenkopi Formation in the southwestern United States. This ichnoassemblage provides the first opportunity to observe paleoecological diversity and associated paleoenvironments within the Lower Triassic of the Chugwater Group.
Lovelace, D. M., and S. D. Lovelace. 2012. Paleoenvironments and paleoecology of a Lower Triassic invertebrate and vertebrate ichnoassemblage from the Red Peak Formation (Chugwater Group), central Wyoming. Palaios 27:636-657. doi: 10.2110/palo.2012.p12-011r
Abstract - The Lower Triassic Red Peak Formation of the Chugwater Group has long been considered to have an extremely poor paleontological record, although the cause for the apparent dearth of fossils has yet to be been determined. During the course of fieldwork in central Wyoming numerous vertebrate and invertebrate ichnogenera (n ≥ 11) were observed. Vertebrate tracks and trackways representative of dinosauromorph, archosaur, lepidosaur, and testudinate trackmakers were found (cf. Rotodactylus, Chirotherium barthii, Rhynchosauroides, and cf. Chelonipus respectively). An invertebrate ichnoassemblage composed of at least 6 ichnogenera consistent with the Scoyenia ichnofacies were also found (e.g., Diplichnites, Lockeia, Fuersichnus communis, Palaeophycus striatus, cf. Scoyenia, and cf. Scolicia). The majority of these tracks and traces were found in the upper platy facies (upper 10–20 m of the Red Peak Formation), which is thought to be no younger than upper Spathian in age. Sedimentary structures, architectural elements, and lateral stratigraphic relationships support the interpretation of floodplain, fluvial, and lacustrine deposition for the upper platy facies in central Wyoming. The Red Peak Formation vertebrate and invertebrate ichnoassemblages, along with their associated depositional environments, are consistent with a fluviolacustrine (continental) setting comparable to those described from Lower to Middle Triassic strata with a Pangean distribution, including the Moenkopi Formation in the southwestern United States. This ichnoassemblage provides the first opportunity to observe paleoecological diversity and associated paleoenvironments within the Lower Triassic of the Chugwater Group.
A New Ctenosauriscid from Eastern Europe, Bystrowisuchus flerovi May Represent the Oldest Known Crown-Group Archosaur
This paper describes a new ctenosauriscid archosaur from the Early Triassic of Europe. Bystrowisuchus flerovi is based upon a series of fragmentary cervical vertebrae and a partial right ilium. It differs from other ctenosauriscids in the presence of expanded spine tables on the apices of the neural spines, and by possessing generally shorter neural spines. Based on these characters Sennikov considers Bystrowisuchus to be transitional between rauisuchids and ctenosauriscids. Note that Sennikov prefers to use traditional Linnaean systematics rather than cladistics (and still recognizes Thecodontia as a taxonomic entity). A new family Lotosauridae is erected and considered distinct from other ctenosauriscids [Ctenosauriscidae]. The type locality is dated latest Olenekian, which means that Bystrowisuchus is probably older than Xilousuchus which is ambiguously from the latest Olenekian-early Anisian of China and therefore could represent the oldest record of a ctenosauriscid and crown-group archosaur.
Sennikov, A. G. 2012. The first ctenosauriscid (Reptilia: Archosauromorpha) from the Lower Triassic of Eastern Europe. Paleontological Journal [Paleontologicheskii Zhurnal] 46:499-511.
Abstract - A new Early Triassic thecodont from the Donskaya Luka locality is described. A new species and genus of Rauisuchidae, Bystrowisuchus flerovi gen. et sp. nov., the first East European and earliest known member of the family Ctenosauriscidae is established. The taxonomy and phylogeny of Rauisuchidae and their stratigraphical and geographical distribution in connection with new finds are discussed.
First Procolophonid from the Lower Triassic of Madagascar
Falconnet, J., Andriamihaja, M., Läng, É., and J.-S. Steyer. 2012. First procolophonid (Reptilia, Parareptilia) from the Lower Triassic of Madagascar. Comptes Rendus Palevol (advance online publication) http://dx.doi.org/10.1016/j.crpv.2012.04.001
Abstract - Lasasaurus beltanae nov. gen. nov. sp., a new procolophonid (Reptilia, Parareptilia) from the Lower Triassic of Madagascar, is represented by a single partial skeleton preserved in a ferro-calcareous nodule from the Middle Sakamena Formation, in the North of the island. This new taxon is unique in possessing peculiar, fine and dendritic crests running along the posterolateral side of the squamosal, widely spaced maxillary teeth, subparallel mesiodistal ridges connecting maxillary teeth to the tooth row, and a strongly acute anterior margin of the copula (hyoid bone). This well-preserved specimen belongs to a juvenile individual. The inclusion of L. beltanae nov. gen. nov. sp. in a phylogenetic analysis suggests that it is close to Theledectinae, Procolophoninae, and Leptopleurinae, though their respective relationships are uncertain. This specimen is the first procolophonid described from Madagascar and represents a minor terrestrial component of a coastal vertebrate assemblage dominated by amphibious to fully-aquatic taxa.
Abstract - Lasasaurus beltanae nov. gen. nov. sp., a new procolophonid (Reptilia, Parareptilia) from the Lower Triassic of Madagascar, is represented by a single partial skeleton preserved in a ferro-calcareous nodule from the Middle Sakamena Formation, in the North of the island. This new taxon is unique in possessing peculiar, fine and dendritic crests running along the posterolateral side of the squamosal, widely spaced maxillary teeth, subparallel mesiodistal ridges connecting maxillary teeth to the tooth row, and a strongly acute anterior margin of the copula (hyoid bone). This well-preserved specimen belongs to a juvenile individual. The inclusion of L. beltanae nov. gen. nov. sp. in a phylogenetic analysis suggests that it is close to Theledectinae, Procolophoninae, and Leptopleurinae, though their respective relationships are uncertain. This specimen is the first procolophonid described from Madagascar and represents a minor terrestrial component of a coastal vertebrate assemblage dominated by amphibious to fully-aquatic taxa.
Further Evidence of Burrowing in Procolophonid Parareptiles
MacDougall, M. J., Modesto, S. P., and J. Botha-Brink. 2012. The postcranial skeleton of the Early Triassic parareptile Sauropareion anoplus, with a discussion of possible life history. Acta Palaeontologica Polonica in press. Available
online 27 Feb 2012 doi: http://dx.doi.org/10.4202/app.2011.0099.
Earliest Evidence of Ovoviviparity in Coelocanths
Wen, W., Zhang, Q.-Y., Hu, S.-X., Benton, M. J., Zhou, C.-Y., Tao, X., Yuan, H.-J., and Z.-Q., Chen. 2012. Coelacanths from the Middle Triassic Luoping Biota, Yunnan, South China, with the earliest evidence of ovoviviparity. Acta Palaeontologica Polonica in press. Available online 08 Mar 2012 doi: http://dx.doi.org/10.4202/app.2011.0066
Abstract - The fossil record of coelacanths is patchy, with very few taxa known from the
Triassic of Asia. We report here two new genera and species of coelacanths from
the Luoping Biota, a recently found site of exceptional fossil preservation from
Yunnan, South China. The first new taxon, Luopingcoelacanthus eurylacrimalis, is
based on four specimens, which together show most aspects of the anatomy. One
specimen shows two small coelacanths inside the ventral portion of the abdominal
cavity, and these are interpreted as intrauterine embryos, close to birth size,
based on comparisons with previously reported embryos of the fossil coelacanths
Rhabdoderma and Undina, and the extant genus Latimeria. Our new find extends the
evidence for ovoviviparity in coelacanths back from the Late Jurassic to the
Middle Triassic. The second new taxon, Yunnancoelacanthus acrotuberculatus, is
based on one specimen, and differs from Luopingcoelacanthus in the dentary,
lachrymojugal, number of rays of the first dorsal fin, and especially in the
ornament on dermal bones and scales. A cladistic analysis shows that the new
taxa are closest relatives to the derived clade Latimerioidei. The relatively
high diversity of coelacanths in the Early Triassic, and adaptations of living
Latimeria to low-oxygen conditions, suggests that the group may have included
‘disaster taxa’ that benefited from anoxic and dysoxic ocean conditions in the
aftermath of the end-Permian mass extinction.
Panchetocynodon damodarensis, a New Cynodont from the Lower Triassic of India
Das, D. P., and A. Gupta. 2012. New cynodont record from the lower Triassic Panchet Formation, Damodar valley. Earth and Environmental Science Journal of the Geological Society of India Volume 79, Number 2, 175-180 DOI: 10.1007/s12594-012-0022-2
Abstract - This paper reports the find of a new non-mammalian cynodont from the Lower Triassic Panchet Formation of the Damodar valley, West Bengal, India. The fossil, recovered from a clay pellet rich calcareous sandstone bed, is a part of left lower jaw having five post canines that are damaged to various extents. A combination of mammal-like advanced characters such as much enlarged dentary, reduced post dentary bones, high coronoid process, large masseteric fossa, each post canine with a large central cusp flanked by a distal and a mesial accessory cusps with two additional lingually positioned cingular cusps, incipient root division and clearly demarcated crown-root juncture prompted to erect a new taxon Panchetocynodon damodarensis gen. et sp. nov.
Redescription of the Sail-backed Poposauroid Ctenosauriscus from the Early Triassic of Germany
Available now at PLoSONE is a redescription of this important historic Triassic taxon which is the namesake of a clade of sail-backed poposauroid archosaurs that have come into recent prominence given the discovery of a well-preserved specimen of Arizonasaurus babbitti in 2002.
Butler, R. J., Brusatte, S. L., Reich, M., Nesbitt, S. J., Schoch, R. R., and J. J. Hornung. 2011. The sail-backed reptile Ctenosauriscus from the latest Early Triassic of Germany and the timing and biogeography of the early archosaur radiation. PLoS ONE 6(10): e25693. doi:10.1371/journal.pone.0025693
Background
Archosaurs (birds, crocodilians and their extinct relatives including dinosaurs) dominated Mesozoic continental ecosystems from the Late Triassic onwards, and still form a major component of modern ecosystems (>10,000 species). The earliest diverse archosaur faunal assemblages are known from the Middle Triassic (c. 244 Ma), implying that the archosaur radiation began in the Early Triassic (252.3–247.2 Ma). Understanding of this radiation is currently limited by the poor early fossil record of the group in terms of skeletal remains.
Methodology/Principal Findings
We redescribe the anatomy and stratigraphic position of the type specimen of Ctenosauriscus koeneni (Huene), a sail-backed reptile from the Early Triassic (late Olenekian) Solling Formation of northern Germany that potentially represents the oldest known archosaur. We critically discuss previous biomechanical work on the ‘sail’ of Ctenosauriscus, which is formed by a series of elongated neural spines. In addition, we describe Ctenosauriscus-like postcranial material from the earliest Middle Triassic (early Anisian) Röt Formation of Waldhaus, southwestern Germany. Finally, we review the spatial and temporal distribution of the earliest archosaur fossils and their implications for understanding the dynamics of the archosaur radiation.
Conclusions/Significance
Comprehensive numerical phylogenetic analyses demonstrate that both Ctenosauriscus and the Waldhaus taxon are members of a monophyletic grouping of poposauroid archosaurs, Ctenosauriscidae, characterised by greatly elongated neural spines in the posterior cervical to anterior caudal vertebrae. The earliest archosaurs, including Ctenosauriscus, appear in the body fossil record just prior to the Olenekian/Anisian boundary (c. 248 Ma), less than 5 million years after the Permian–Triassic mass extinction. These earliest archosaur assemblages are dominated by ctenosauriscids, which were broadly distributed across northern Pangea and which appear to have been the first global radiation of archosaurs.
New Capitosaur from the Early Triassic of Poland
Sulej, T., and G. Niedźwiedzki. in press. A new large capitosaur temnospondyl amphibian from the Early Triassic of Poland. Acta Palaeontologica Polonica available online 09 Sep 2011 doi:10.4202/app.2011.0025
New Vertebrate Locality from the Lower Triassic of Brazil
The taxonomic diversity of these Gondwanan sites is incredible. I'd love to find even fragmentary procolophonids and synapsids in the Chinle.
Dias-da-Silva, S., and Á. A. S. da-Rosa. 2011. Granja Palmeiras, a new fossiliferous site for the Lower Triassic of southern Brazil. Revista Brasileira de Paleontologia 14(2):157-168 doi:10.4072/rbp.2011.2.04
Abstract - A new fossiliferous locality, Granja Palmeiras, is described for the Sanga do Cabral Formation (Lower Triassic of Southern Brazil, Rosário do Sul Group, Paraná Basin). It consists on orange and reddish fine sandstones, with sandy and calcareous concretions and intercalated fossiliferous intraformational conglomerates. Its fossils are fragmentary and badly preserved. Nevertheless, among the 46 specimens collected so far, putative actinopterygians,temnospondyls, procolophonoids, archosauromorphs, and non-mammalian cynodonts were identified. Besides, several non-diagnostic appendicular elements are ascribed to Tetrapoda indet. The fossiliferous content found in Granja Palmeiras can provide a valuable new framework for future correlation with other Lower Triassic South American units as well as other continental tetrapod- bearing deposits from Gondwana.
Dias-da-Silva, S., and Á. A. S. da-Rosa. 2011. Granja Palmeiras, a new fossiliferous site for the Lower Triassic of southern Brazil. Revista Brasileira de Paleontologia 14(2):157-168 doi:10.4072/rbp.2011.2.04
Abstract - A new fossiliferous locality, Granja Palmeiras, is described for the Sanga do Cabral Formation (Lower Triassic of Southern Brazil, Rosário do Sul Group, Paraná Basin). It consists on orange and reddish fine sandstones, with sandy and calcareous concretions and intercalated fossiliferous intraformational conglomerates. Its fossils are fragmentary and badly preserved. Nevertheless, among the 46 specimens collected so far, putative actinopterygians,temnospondyls, procolophonoids, archosauromorphs, and non-mammalian cynodonts were identified. Besides, several non-diagnostic appendicular elements are ascribed to Tetrapoda indet. The fossiliferous content found in Granja Palmeiras can provide a valuable new framework for future correlation with other Lower Triassic South American units as well as other continental tetrapod- bearing deposits from Gondwana.
RESUMO – Uma nova localidade fossilífera, Granja Palmeiras, é descrita para a Formação Sanga do Cabral (Triássico Inferior do sul do Brasil, Grupo Rosário do Sul, bacia do Paraná). Consiste em arenitos finos alaranjados e avermelhados, com concreções carbonáticas e arenosas, e conglomerados intraformacionais intercalados. Os fósseis se apresentam fragmentários e em mal estado de preservação. Mesmo assim, dentre os 46 espécimes coletados até o momento foram identificados restos de actinopterígios, temnospôndilos, procolofonóides, arcossauromorfos e prováveis cinodontes não-mamalianos. Além destes, vários elementos apendiculares não diagnósticos são atribuídos a Tetrapoda indet. O conteúdo fossilífero registrado na Granja Palmeiras pode fornecer informações valiosas para a correlação com outras unidades do Triássico Inferior sul-americano, bem como com outras localidades gondwânicas de outras regiões do globo.
New Record of Large Archosauromorphs from the Early Triassic of Antarctica
Smith, N. D., Crandall, J. R., Hellert, S. M., Hammer, W. R., and P. J. Makovicky. 2011. Anatomy and affinities of large archosauromorphs from the lower Fremouw Formation (Early Triassic) of Antarctica. Journal of Vertebrate Paleontology 31:784-797. DOI:10.1080/02724634.2011.586662
Abstract - The vertebrate assemblage of the lower Fremouw Formation has been studied for nearly 50 years, but many components remain poorly known. We describe a partial presacral vertebra and the distal end of a left humerus collected just above the Permian–Triassic boundary in the Shackleton Glacier region of the central Transantarctic Mountains. Our identification of these specimens as archosauromorphs that represent at least one taxon of large-bodied archosauriform increases the known reptile diversity of the Fremouw Formation considerably, and provides the first definitive evidence for the presence of Archosauriformes in the Early Triassic of Antarctica. These records increase faunal similarities between the lower Fremouw Formation and other Early Triassic assemblages. Although the lower Fremouw assemblage is typically considered a subset of the coeval Lystrosaurus Assemblage Zone (LAZ) of South Africa, the discrepancy in inferred body size between the Antarctic specimens and Proterosuchus fergusi, coupled with the fact that the LAZ of the Karoo Basin has been sampled much more thoroughly, suggests a real disparity in the maximum body size of apex carnivores between the lower Fremouw assemblage and the LAZ. The lower Fremouw specimens also demonstrate that one or more lineages of archosauriform had attained the large body size characteristic of later members of the clade very soon after the end-Permian mass extinction. This offers a point of contrast with the global pattern of post-extinction terrestrial communities, which are typified by a marked reduction in body size (the ‘Lilliput effect’).
Abstract - The vertebrate assemblage of the lower Fremouw Formation has been studied for nearly 50 years, but many components remain poorly known. We describe a partial presacral vertebra and the distal end of a left humerus collected just above the Permian–Triassic boundary in the Shackleton Glacier region of the central Transantarctic Mountains. Our identification of these specimens as archosauromorphs that represent at least one taxon of large-bodied archosauriform increases the known reptile diversity of the Fremouw Formation considerably, and provides the first definitive evidence for the presence of Archosauriformes in the Early Triassic of Antarctica. These records increase faunal similarities between the lower Fremouw Formation and other Early Triassic assemblages. Although the lower Fremouw assemblage is typically considered a subset of the coeval Lystrosaurus Assemblage Zone (LAZ) of South Africa, the discrepancy in inferred body size between the Antarctic specimens and Proterosuchus fergusi, coupled with the fact that the LAZ of the Karoo Basin has been sampled much more thoroughly, suggests a real disparity in the maximum body size of apex carnivores between the lower Fremouw assemblage and the LAZ. The lower Fremouw specimens also demonstrate that one or more lineages of archosauriform had attained the large body size characteristic of later members of the clade very soon after the end-Permian mass extinction. This offers a point of contrast with the global pattern of post-extinction terrestrial communities, which are typified by a marked reduction in body size (the ‘Lilliput effect’).
Review of the Lower Triassic Temnospondyl Fauna of Germany
Schoch, R. R. 2011. How diverse is the temnospondyl fauna in the Lower Triassic of southern Germany? Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 261:49-60. DOI: 10.1127/0077-7749/2011/0147
Abstract - Among the few fossiliferous Lower Triassic deposits in Europe, the Lower to Middle Buntsandstein of the German southwest has yielded a range of interesting finds. A review of the published and new material gives the following results: (1) The oldest identified remain is a mandible of a small stereospondyl from the Bernburg Formation (Induan); (2) A new palate from the early Olenekian (Badischer Bausandstein) stems from a basal capitosaur similar to Wetlugasaurus; (3) In the late Olenekian (Hardegsen Formation), two well-defined temnospondyl genera are present: the basal capitosauroids Meyerosuchus fuerstenbergianus and Odenwaldia heidelbergensis. Large remains formerly referred to Mastodonsaurus either pertain to a different family or are undiagnostic, pushing the first occurrence of mastodonsaurids into the Anisian. These finds highlight the presence of large aquatic predators by early Triassic time, revealing an increasing diversity of aquatic predators from the Induan to the Anisian. The documented faunal changes involved patterns of immigration and extinction/emigration rather than endemic evolution within the basin. In contrast to the northern parts of the basin, the genera Trematosaurus, Parotosuchus, and Sclerothorax are absent in the southern part, where Meyerosuchus and Odenwaldia existed.
Abstract - Among the few fossiliferous Lower Triassic deposits in Europe, the Lower to Middle Buntsandstein of the German southwest has yielded a range of interesting finds. A review of the published and new material gives the following results: (1) The oldest identified remain is a mandible of a small stereospondyl from the Bernburg Formation (Induan); (2) A new palate from the early Olenekian (Badischer Bausandstein) stems from a basal capitosaur similar to Wetlugasaurus; (3) In the late Olenekian (Hardegsen Formation), two well-defined temnospondyl genera are present: the basal capitosauroids Meyerosuchus fuerstenbergianus and Odenwaldia heidelbergensis. Large remains formerly referred to Mastodonsaurus either pertain to a different family or are undiagnostic, pushing the first occurrence of mastodonsaurids into the Anisian. These finds highlight the presence of large aquatic predators by early Triassic time, revealing an increasing diversity of aquatic predators from the Induan to the Anisian. The documented faunal changes involved patterns of immigration and extinction/emigration rather than endemic evolution within the basin. In contrast to the northern parts of the basin, the genera Trematosaurus, Parotosuchus, and Sclerothorax are absent in the southern part, where Meyerosuchus and Odenwaldia existed.
Redescription of a Lower Triassic Synapsid and a Reappraissal of Lower Triassic Therocephalian Biostratigraphy
Botha-Brink, J., and S. P. Modesto. 2011. A new skeleton of the Therocephalian synapsid Olivierosuchus parringtoni from the Lower Triassic South African Karoo Basin. Palaeontology Early View. DOI: 10.1111/j.1475-4983.2011.01048.x
Abstract - We provide a redescription of the therocephalian therapsid Olivierosuchus parringtoni based on a new specimen recovered from the Lower Triassic Lystrosaurus Assemblage Zone of South Africa and discuss the biostratigraphic implications of Lower Triassic South African therocephalians. The new specimen comprises a skull and articulated anterior portion of the postcranial skeleton. Olivierosuchus parringtoni can be distinguished from its akidnognathid relatives, Promoschorhynchus and Moschorhinus, by the presence of a relatively slender snout. Features that further distinguish Olivierosuchus from Promoschorhynchus include fewer upper postcanines, an obtuse angle of the transverse process of the pterygoid and an oblique alignment of the suborbital fenestra margin of the palatine. Features that further distinguish Olivierosuchus from Moschorhinus include the presence of a sharp rather than blunt crista choanalis, a spatulate posterior portion of the ectopterygoid instead of a narrow shaft, the presence of prominent pterygoid tuberosities and a narrow, elongated tabular. A reappraisal of Lower Triassic therocephalian biostratigraphy reveals that most of these taxa are restricted to the lowermost part of the Lystrosaurus Assemblage Zone revealing a high diversity, whereafter the diversity decreases dramatically in the middle of the zone. However, despite their scarcity in the middle and upper Lystrosaurus Assemblage Zone, therocephalians in the Karoo Basin remain the most diverse therapsid clade in the lowermost Triassic, which suggests that they were able to recover relatively quickly from the end-Permian extinction event and form an important part of the postextinction earliest Triassic recovery.
Abstract - We provide a redescription of the therocephalian therapsid Olivierosuchus parringtoni based on a new specimen recovered from the Lower Triassic Lystrosaurus Assemblage Zone of South Africa and discuss the biostratigraphic implications of Lower Triassic South African therocephalians. The new specimen comprises a skull and articulated anterior portion of the postcranial skeleton. Olivierosuchus parringtoni can be distinguished from its akidnognathid relatives, Promoschorhynchus and Moschorhinus, by the presence of a relatively slender snout. Features that further distinguish Olivierosuchus from Promoschorhynchus include fewer upper postcanines, an obtuse angle of the transverse process of the pterygoid and an oblique alignment of the suborbital fenestra margin of the palatine. Features that further distinguish Olivierosuchus from Moschorhinus include the presence of a sharp rather than blunt crista choanalis, a spatulate posterior portion of the ectopterygoid instead of a narrow shaft, the presence of prominent pterygoid tuberosities and a narrow, elongated tabular. A reappraisal of Lower Triassic therocephalian biostratigraphy reveals that most of these taxa are restricted to the lowermost part of the Lystrosaurus Assemblage Zone revealing a high diversity, whereafter the diversity decreases dramatically in the middle of the zone. However, despite their scarcity in the middle and upper Lystrosaurus Assemblage Zone, therocephalians in the Karoo Basin remain the most diverse therapsid clade in the lowermost Triassic, which suggests that they were able to recover relatively quickly from the end-Permian extinction event and form an important part of the postextinction earliest Triassic recovery.
New Skull Material from an Early Triassic Procolophonid
Macdougall, M. J., and S. P. Modesto. 2011. New information on the skull of the Early Triassic parareptile Sauropareion anoplus, with a discussion of tooth attachment and replacement in procolophonids. Journal of Vertebrate Paleontology 31:270-278. DOI: 10.1080/02724634.2011.549436
Abstract- A partial reptile skull collected from the Lower Triassic (Induan) Barendskraal locality of South Africa is referable to the procolophonid parareptile Sauropareion anoplus. The specimen comprises the left side of the skull roof, palate, and mandible, and preserves areas not preserved or accessible in the skulls of previously published specimens, including fragmentary remains of the premaxilla, the anterior end of the maxilla, and the anterior end and lingual aspect of the mandible. The maxilla exhibits a maxillary depression that is similar in both shape and relative size to that seen in Procolophon trigoniceps, an anterolateral maxillary foramen that is indistinguishable from those seen in other procolophonoids, and 11 conical teeth. The suborbital foramen is formed ventrally by the palatine and the ectopterygoid. The dentary and the coronoid are fused together indistinguishably in lateral aspect. The marginal teeth appear to be anchored to the jaws by bone of attachment. The dentary teeth are exposed in lingual aspect and appear to be ankylosed to the summit of the bone, suggesting acrodont tooth implantation. Tooth replacement is seen in these teeth, where the lingual surface of a single tooth crown base in the middle of the dentary series is excavated for the apex of a replacement tooth crown, but the excavation does not extend ventrally onto the lingual surface of the bone. Considering that no extant reptiles with acrodont tooth implantation exhibit tooth replacement or bone of attachment, we tentatively regard protothecodonty to be present in S. anoplus.
Abstract- A partial reptile skull collected from the Lower Triassic (Induan) Barendskraal locality of South Africa is referable to the procolophonid parareptile Sauropareion anoplus. The specimen comprises the left side of the skull roof, palate, and mandible, and preserves areas not preserved or accessible in the skulls of previously published specimens, including fragmentary remains of the premaxilla, the anterior end of the maxilla, and the anterior end and lingual aspect of the mandible. The maxilla exhibits a maxillary depression that is similar in both shape and relative size to that seen in Procolophon trigoniceps, an anterolateral maxillary foramen that is indistinguishable from those seen in other procolophonoids, and 11 conical teeth. The suborbital foramen is formed ventrally by the palatine and the ectopterygoid. The dentary and the coronoid are fused together indistinguishably in lateral aspect. The marginal teeth appear to be anchored to the jaws by bone of attachment. The dentary teeth are exposed in lingual aspect and appear to be ankylosed to the summit of the bone, suggesting acrodont tooth implantation. Tooth replacement is seen in these teeth, where the lingual surface of a single tooth crown base in the middle of the dentary series is excavated for the apex of a replacement tooth crown, but the excavation does not extend ventrally onto the lingual surface of the bone. Considering that no extant reptiles with acrodont tooth implantation exhibit tooth replacement or bone of attachment, we tentatively regard protothecodonty to be present in S. anoplus.
A New South African Therapsid in the Newest Issue of JVP
Quite a few Triassic papers in the new issue of JVP. Here is one:
Huttenlocker, A. K., Sidor, C. A., and R. M. H. Smith. 2011. A new specimen of Promoschorhynchus (Therapsida: Therocephalia: Akidnognathidae) from the Lower Triassic of South Africa and its implications for theriodont survivorship across the Permo-Triassic boundary. Journal of Vertebrate Paleontology 31:405-421. DOI: 10.1080/02724634.2011.546720
Abstract - The anatomy of a new subadult specimen of eutherocephalian therapsid, attributed to Promoschorhynchus cf. P. platyrhinus, is described from lowermost Triassic Lystrosaurus Assemblage Zone strata in the main Karoo Basin of South Africa. The specimen preserves information previously unknown in the genus, including details of the posterior region of the skull and intertemporal region, and a partial (though disarticulated) postcranial skeleton. A cladistic analysis of 32 therapsid taxa, including 24 Permo-Triassic therocephalian genera, and 121 craniodental and postcranial characters supports the specimen's placement within the Permian akidnognathid genus Promoschorhynchus (making it the youngest documented occurrence of this taxon) within a monophyletic Therocephalia. Inclusion of new postcranial characters strengthens support of the therocephalian clade. The new record of Promoschorhynchus offers insights into the diversity of eutheriodonts across the Permo-Triassic boundary (PTB) in the Karoo Basin. In contrast to cynodonts, therocephalians exhibited decreased rates of cladogenesis across the PTB, with several Triassic lineages having roots in the Late Permian rather than representing earliest Triassic radiations.
Huttenlocker, A. K., Sidor, C. A., and R. M. H. Smith. 2011. A new specimen of Promoschorhynchus (Therapsida: Therocephalia: Akidnognathidae) from the Lower Triassic of South Africa and its implications for theriodont survivorship across the Permo-Triassic boundary. Journal of Vertebrate Paleontology 31:405-421. DOI: 10.1080/02724634.2011.546720
Abstract - The anatomy of a new subadult specimen of eutherocephalian therapsid, attributed to Promoschorhynchus cf. P. platyrhinus, is described from lowermost Triassic Lystrosaurus Assemblage Zone strata in the main Karoo Basin of South Africa. The specimen preserves information previously unknown in the genus, including details of the posterior region of the skull and intertemporal region, and a partial (though disarticulated) postcranial skeleton. A cladistic analysis of 32 therapsid taxa, including 24 Permo-Triassic therocephalian genera, and 121 craniodental and postcranial characters supports the specimen's placement within the Permian akidnognathid genus Promoschorhynchus (making it the youngest documented occurrence of this taxon) within a monophyletic Therocephalia. Inclusion of new postcranial characters strengthens support of the therocephalian clade. The new record of Promoschorhynchus offers insights into the diversity of eutheriodonts across the Permo-Triassic boundary (PTB) in the Karoo Basin. In contrast to cynodonts, therocephalians exhibited decreased rates of cladogenesis across the PTB, with several Triassic lineages having roots in the Late Permian rather than representing earliest Triassic radiations.
New Tanystropheids from the Early Triassic of Europe
I don't have access to this article, only the abstract.
Sennikov, A.G. 2011. New Tanystropheids (Reptilia: Archosauromorpha) from the Triassic of Europe. Palaeontological Journal 45:95-104. DOI: 10.1134/S0031030111010151
Abstract—A new prolacertilian species and genus, Augustaburiania vatagini gen. et sp. nov. (Reptilia: Archosauromorpha), from the Lower Triassic of the Don River Basin is described. It is the first representative of the Tanystropheidae in the Eastern Europe and the world oldest member of this family. Another new genus (Protanystropheus gen. nov.) from Central and Western Europe is also established. The diversity, systematics, phylogeny, evolution, and stratigraphic and geographical distribution of prolacertilians are discussed. The ecological role of prolacertilians in Early Triassic communities and adaptation to marine environments are analyzed.
Sennikov, A.G. 2011. New Tanystropheids (Reptilia: Archosauromorpha) from the Triassic of Europe. Palaeontological Journal 45:95-104. DOI: 10.1134/S0031030111010151
Abstract—A new prolacertilian species and genus, Augustaburiania vatagini gen. et sp. nov. (Reptilia: Archosauromorpha), from the Lower Triassic of the Don River Basin is described. It is the first representative of the Tanystropheidae in the Eastern Europe and the world oldest member of this family. Another new genus (Protanystropheus gen. nov.) from Central and Western Europe is also established. The diversity, systematics, phylogeny, evolution, and stratigraphic and geographical distribution of prolacertilians are discussed. The ecological role of prolacertilians in Early Triassic communities and adaptation to marine environments are analyzed.
"Triassic Attack"
Unfortunately (or maybe not) I missed this movie, which aired in the U.S. last Saturday, about a Native American curse that causes roadside dinosaur attractions to come alive and eat everything. Despite being called "Triassic Attack" the main culprits are reportedly a Tyrannosaurus and a Cretaceous age pterosaur. Based on the previews and other comments it was probably pretty enjoyably horrible as a B-movie should be, but I am dissapointed that the producers didn't educate themselves a bit and use actual Triassic critters.
Did anyone see this and care to report?
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