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Originally published, uncorrected article. https://doi.org/10.1371/journal.pone.0093657.s001 (PDF) File S2. Nesbitt SJ, Butler RJ, Gower DJ (2013) A New Archosauriform (Reptilia: Diapsida) from the Manda Beds (Middle Triassic) of Southwestern Tanzania.

There were three typographical errors in the second and third paragraphs of the Introduction. Citation: Salamon MA, Niedźwiedzki R, Lach R, Brachaniec T, Gorzelak P (2013) Correction: Ophiuroids Discovered in the Middle Triassic Hypersaline Environment.

The end‐Triassic extinction (ETE) is one of the most severe biotic crises in the Phanerozoic. This event was synchronous with volcanism of the Central Atlantic Magmatic Province (CAMP), the ultimate cause of the extinction and related environmental perturbations. However, the continental weathering response to CAMP‐induced warming remains poorly constrained. Strontium isotope stratigraphy is a powerful correlation tool that can also provide insights into the changes in weathering regime, but the scarcity of 87Sr/86Sr data across the Triassic‐Jurassic boundary (TJB) hindered the use of this method. Here we present new high‐resolution 87Sr/86Sr data from bulk carbonates at Csővár, a continuous marine section that spans 2.5 Myrs across the TJB. We document a continuing decrease in 87Sr/86Sr ratio from the late Rhaetian to the ETE, terminated by a 300 kyr interval of a flat trend and followed by a transient increase in the early Hettangian that levels off. We suggest that the first in the series of perturbations is linked to the influx of non‐radiogenic Sr from the weathering of freshly erupted CAMP basalts, leading to a delay in the radiogenic continental weathering response. The subsequent rise in 87Sr/86Sr after the TJB is explained by intensified continental crustal weathering from elevated CO2 levels and reduced mantle‐derived Sr flux. Using Sr flux modeling, we also find support for such multiphase, prolonged continental weathering scenarios. Aggregating the new data set with published records employing an astrochronological age model results in a highly resolved Sr isotope reference curve for an 8.5 Myr interval around the TJB. Plain Language Summary The end‐Triassic mass extinction ∼201 million years ago was one of the most severe crises in the history of life, triggered by massive volcanism in areas around the present‐day Central Atlantic Ocean. Although volcanism is expected to produce greenhouse warming through carbon‐dioxide outgassing that leads to increased weathering in the continents, finding direct proof for such a scenario is challenging. We report new measurements of the ratios of strontium isotopes from marine limestones and reconstruct the weathering history at the Triassic‐Jurassic transition. In the ocean, unradiogenic 86Sr isotopes are sourced from submarine volcanism or weathering of fresh volcanic rocks from Earth's mantle, whereas radiogenic 87Sr isotopes are delivered by rivers from weathering of rocks in Earth's continental crust. We find that a steady long‐term decreasing trend in strontium isotope ratio was disturbed by a series of short‐term changes at the end of the Triassic. Supported by modeling, we suggest that these changes reflect the eruption of basalts of the Central Atlantic Magmatic Province and the effect of volcanism in intensifying the continental weathering. Knowing more detail about one component in a cascade of environmental changes ultimately helps our understanding of a critical event in the history of the Earth and its biosphere. Key Points High‐resolution 87Sr/86Sr data spanning 2.5 Myr across the end‐Triassic extinction reveals multiphase perturbation of the marine Sr system Aggregation with other Sr data documents long‐term and short‐term changes over 8.5 Myr during the Triassic‐Jurassic transition Modeling supports the role of Central Atlantic Magmatic Province volcanism in a stepped weathering scenario of fresh basalt and continental crust

Actinopterygians (ray-finned fishes) successfully passed through four of the big five mass extinction events of the Phanerozoic, but the effects of these crises on the group are poorly understood. Many researchers have assumed that the Permo-Triassic mass extinction (PTME) and end-Triassic extinction (ETE) had little impact on actinopterygians, despite devastating many other groups. Here, two morphometric techniques, geometric (body shape) and functional (jaw morphology), are used to assess the effects of these two extinction events on the group. The PTME elicits no significant shifts in functional disparity while body shape disparity increases. An expansion of body shape and functional disparity coincides with the neopterygian radiation and evolution of novel feeding adaptations in the Middle-Late Triassic. Through the ETE, small decreases are seen in shape and functional disparity, but are unlikely to represent major changes brought about by the extinction event. In the Early Jurassic, further expansions into novel areas of ecospace indicative of durophagy occur, potentially linked to losses in the ETE. As no evidence is found for major perturbations in actinopterygian evolution through either extinction event, the group appears to have been immune to two major environmental crises that were disastrous to most other organisms.

A review of the palynofloral succession at the well-documented Triassic–Jurassic boundary sites – Kuhjoch (Austria), St Audrie's Bay (UK), Stenlille (Denmark), Astartekløft (Greenland), Sverdrup Basin (Arctic Canada), Northern Carnarvon Basin (Western Australia), Southeast Queensland (eastern Australia) and New Zealand – show all sites experienced major to moderate re-organization of the terrestrial vegetation during the end-Triassic event. The changes led to subsequent taxonomic losses of between 17% and 73% of the Rhaetian pre-extinction palynoflora. The majority of the typical Rhaetian taxa that disappear are so far not known from in situ occurrences in reproductive structures of macrofossil plant taxa. From an ecological perspective, the most dramatic changes occurred in the Sverdrup Basin, Stenlille, Kuhjoch and Carnarvon Basin, where the pre- and post-extinction palynofloras were fundamentally different in both composition and dominance. These changes correspond to ecological severity Category I of McGhee et al. (2004), while the remaining sites are placed in their Subcategory IIa because there the pre-extinction ecosystems are disrupted, but recover and are not replaced post-extinction. Increased total abundances of spores on both hemispheres during the extinction and recovery intervals may indicate that environmental and/or climatic conditions became less favourable for seed plants. Such conditions may include expected effects of volcanism in the Central Atlantic Magmatic Province, such as acid rain, terrestrial soil and freshwater acidification due to volcanic sulfur dioxide emissions, fluctuating ultraviolet flux due to ozone depletion caused by halogens and halocarbon compounds, and drastic changes in climatic conditions due to greenhouse gas emissions.

Unidirectional breathing probably appeared among ancestral archosaurs during the Early Triassic period, some 250 million years ago, a time of low oxygen levels that might have encouraged evolutionary experimentation with improved ventilation.