Nearly a quarter billion years ago an otter-sized, armored, platypus-faced, marine reptile paddled in tropical lagoons on the shores of islands that would become southern China. This weird species is part of a diverse lineage that was restricted to a few million years and those tropical lagoons.

Wadi Al Hitan, the Valley of the Whales, is a site that’s yielded dozens of skeletons of the early predatory whales Basilosaurus and Dorudon over the last hundred years. Newly uncovered specimens support the idea that it was a calving ground for the dolphin-sized Dorudon, and that those calves were hunted by the much larger Basilosaurus.

Extraordinarily well-preserved fossils discovered from the 1970s to the present day show that all pterosaurs were covered in hair-like fibers known as pycnofibers. Two new pterosaur specimens described by Zixiao Yang and colleagues show that some pycnofibers were actually brush- or tuft-shaped and probably share an evolutionary origin with feathers.

An incredible new specimen of the Early Jurassic genus Stenopterygius found in Germany was studied by Johan Lindgren and colleagues. It preserves skin in detail not previously seen in other ichthyosaur fossils. The team of researchers have learned new details of how ichthyosaurs looked in life, as well as details of their physiology.

Since their discovery and subsequent naming almost 200 years ago plesiosaurs have captured the imagination of people around the world with their dramatic appearance and incredible anatomy. An extremely successful group, plesiosaurs ruled the Mesozoic oceans for millions of years, exploring a wide range of habitats and niches. Despite their iconic nature we still lack a solid understanding about many aspects of their lifestyle. At the center of this discussion is the lingering question of what exactly they used their necks for.

Both hump-nosed species were part of a large radiation of chewing plant-eaters. Detailed comparison of the two species shows that their similarities were superficial.