A rare Ornitholestes dinosaur skeleton is to top Sotheby's Natural History auction in Paris on September 30 with a valuation of $477,218-613,556.
The lot was discovered in the Morrison Formation, which spans the western US, and dates to the late Jurassic period.
Ornitholestes was identified by Henry Fairfield Osborn of the American Museum of Natural History in 1903.
It stood at around 6ft long and is thought to have weighed around 15kg.
Its name, "bird robber", is in reference to an early belief that its powerful arms and whiplike tail were adapted in order to catch birds - although this was challenged soon after.
The lot is sold alongside a set of skeletal maps and permits from the initial excavation.
In November last year, a Diplodocus skeleton sold for £400,000 ($649,880) in a sale at Summer's Place in Sussex, UK.
A Lepidotus Maximus fossilised fish will prove another highlight with an estimate of $340,870-409,044.
Its value derives from its exceptional preservation. The scales are in particularly good condition and it retains its teeth, which are rarely present on comparable examples.
Lepidotus were active between the late Jurassic and middle Cretaceous period and are found all around the world, with this particular specimen discovered in the Solnhofen beds in southern Germany.
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