Manipulonyx reshetovi was an alvarezsaurid theropod dinosaur that lived during the Late Cretaceous, about 70 million years ago, in what is now Mongolia.

Although only known from a partial skeleton, based on its close relatives it would have been about 50cm long (~1'8"), with a narrow snout, a coat of fluffy down-like feathers, long slender legs, and short stout arms with massively enlarged thumb claws. 

Notably the fossil specimen has the best preserved hands known from the parvicursorine subfamily of alvarezsaurs, revealing a surprising arrangement of three ossified conical spikes around the thumb. These hand spikes were positioned pointing forwards, backwards, and inwards, and may have improved the ability to grip with just one functional finger.

"Spike-like" hand bones were also previously reported in 2009 in another parvicursorine, Ceratonykus, suggesting that these structures weren't unique to Manipulonyx.

The paper describing Manipulonyx proposes that alvarezsaurs were ovivores, using their hands to carry and then break open eggs, but I'm personally very skeptical of this idea. I think the myrmecophagy interpretation for these little dinosaurs is still much more likely – they probably did opportunistically raid eggs when they could get them, like many modern predators do, but being specialized for just egg-eating is a big claim that definitely needs more evidence.

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this week's #Paleostream flocking results!!!

today we sketched Megamastax, Ornitholestes, Tanyka, and Eosteus

Microraptor art piece thing.

The earliest stages of the Cretaceous were a time of transition. The conifer and cycad plant communities of the past were being replaced by newly evolved angiosperms. With the change in plants came a change in herbivores and with that too a change in carnivores. Across Laurasia sauropods were disappearing, stegosaurs were supplanted by ankylosaurs, and the old guard of ceratosaurs, carnosaurs, and megalosaurs were being replaced by new clades of coelurosaurs. Much as in the Early and Middle Jurassic, this reshuffling of niches allowed for brief but interesting role reversals. During the Hauterivian stage in central Siberia the small carnivore guild is populated by coelurosaurs and a few odd ceratosaurs. Among this first group are members of the Proceratosauridae, tiny Tyrannosaurs, who primarily prey upon the many local mammals and the occasional early ceratopsian. The apex predator niche is occupied by a gigantic Eudromaeosaur. At just over a ton in mass, it is large enough to prey upon even the relict stegosaurs of the area.

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