Rapid neck elongation in Sauropterygia (Reptilia: Diapsida) revealed by a new basal pachypleurosaur from the Lower Triassic of China.

Neck elongation has appeared independently in several tetrapod groups, including giraffes and sauropod dinosaurs on land, birds and pterosaurs in the air, and sauropterygians (plesiosaurs and relatives) in the oceans. Long necks arose in Early Triassic sauropterygians, but the nature and rate of that elongation has not been documented. Here, we report a new species of pachypleurosaurid sauropterygian, Chusaurus xiangensis gen.

First filter feeding in the Early Triassic: cranial morphological convergence between Hupehsuchus and baleen whales.

Modern baleen whales are unique as large-sized filter feeders, but their roles were replicated much earlier by diverse marine reptiles of the Mesozoic. Here, we investigate convergence in skull morphology between modern baleen whales and one of the earliest marine reptiles, the basal ichthyosauromorph Hupehsuchus nanchangensis, from the Early Triassic, a time of rapid recovery of life following profound mass extinction. Two new specimens reveal the skull morphology especially in dorsal view.

The oldest record of Saurosphargiformes (Diapsida) from South China could fill an ecological gap in the Early Triassic biotic recovery.

Diversification following the end-Permian mass extinction marks the initiation of Mesozoic reptile dominance and of modern marine ecosystems, yet major clades are best known from the Middle Triassic suggesting delayed recovery, while Early Triassic localities produce poorly preserved specimens or have restricted diversity. Here we describe gen. et sp.

An injured pachypleurosaur (Diapsida: Sauropterygia) from the Middle Triassic Luoping Biota indicating predation pressure in the Mesozoic.

The Middle Triassic Luoping Biota in south-west China represents the inception of modern marine ecosystems, with abundant and diverse arthropods, fishes and marine reptiles, indicating recovery from the Permian-Triassic mass extinction. Here we report a new specimen of the predatory marine reptile Diandongosaurus, based on a nearly complete skeleton. The specimen is larger than most other known pachypleurosaurs, and the body shape, caniniform teeth, clavicle with anterior process, and flat distal end of the anterior caudal ribs show its affinities with Diandongosaurus acutidentatus, while the new specimen is approximately three times larger than the holotype.

Early Triassic marine reptile representing the oldest record of unusually small eyes in reptiles indicating non-visual prey detection.

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.

Response to comment on "lethally hot temperatures during the Early Triassic greenhouse".

Goudemand et al. replot a subset of our well-constrained data using a new Early Triassic biostratigraphic scheme based on a lower-resolution ammonoid zonation scheme and hypothetical ammonoid-conodont correlation to produce a less distinct seawater temperature history. We dispute their unsubstantiated correlation and, consequently, their allegations.

Lethally hot temperatures during the Early Triassic greenhouse.

Global warming is widely regarded to have played a contributing role in numerous past biotic crises. Here, we show that the end-Permian mass extinction coincided with a rapid temperature rise to exceptionally high values in the Early Triassic that were inimical to life in equatorial latitudes and suppressed ecosystem recovery. This was manifested in the loss of calcareous algae, the near-absence of fish in equatorial Tethys, and the dominance of small taxa of invertebrates during the thermal maxima.

[Safety and efficiency of pacing at right ventricular outflow versus at ventricular cardiac apex].

Objective: To compare the safety and efficiency of pacing at right ventricular outflow versus right ventricular apex.

Method: Patients were divided into two groups: pacing at ventricular cardiac apex (common pacing group, n = 22) and pacing at right ventricular outflow tract (uncommon pacing group, n = 18).

Results: Impedance and amplitude of R-wave were similar during implantation between the two groups (all P > 0.

[Report on initiating clinical research for electrical and mechanical synchronism of selective region pacing in the right ventricular].

Objective: To verify the electric synchronism, mechanic synchronism and hemodynamics of selective site pacing.

Methods: Pacing in the right ventricular cardiac apex (RVA), the right ventricular His bundle region (His), and the septum of right ventricular high-positioned outflow tract (RVOT), CO and CI were recorded. The electrical synchronism was assessed by observing the width and shape in a 12-lead surface ECG.