Halszkaraptor


Halszkaraptor (/ˈhɑːlʃkəræptər/; meaning "Halszka's seizer") is a genus of waterfowl-like dromaeosaurid dinosaurs from Mongolia that lived during the Late Cretaceous period. It contains only one known species, Halszkaraptor escuilliei.

The type specimen (holotype) has been compared to the bones of extant crocodilians and aquatic birds, and found evidence of a semiaquatic lifestyle,[1] while some researchers question about semiaquatic ecology.[2][3] A phylogenetic analysis revealed it was a member of the basal subfamily Halszkaraptorinae, along with Mahakala and Hulsanpes.

The holotype specimen of Halszkaraptor likely came from the Djadochta Formation at Ukhaa Tolgod in southern Mongolia, and was illegally removed by fossil poachers. The fossil found its way to Japan and Great Britain, being owned by several collectors for some years until the Eldonia company of fossil dealer François Escuillié obtained it. He identified it as a new species, and in 2015 took it to the Royal Belgian Institute of Natural Sciences in Brussels, showing it to paleontologists Pascal Godefroit and Andrea Cau for further verification. After verifying its authenticity, among other means by scanning it with synchrotron radiation, a beam of X-rays, at the European Synchrotron Radiation Facility, Cau and other prominent paleontologists described the genus in a detailed study published in the journal Nature. The fossil was returned to the Mongolian authorities.[1][4]

The holotype, MPC D-102/109, was found in a layer of orange sandstone of the Bayn Dzak Member of the Djadochta Formation, dating from the late Campanian, about seventy-five million years old. It consists of a relatively complete skeleton with skull. In 2017, the fossil was not further prepared. Work by the fossil dealers had at that point generally exposed the left side of the skeleton. The synchrotron revealed that the bones continued into the rock and that the piece was probably not a chimaera, an artificial assembly of bones of disparate species, though the top of the snout had been restored with plaster and some elements had been reattached to the rock by glue. The skeleton is largely articulated and not compressed. It represents a subadult individual, about one year old.[1]

The type species Halszkaraptor escuilliei was in 2017 named and described by Andrea Cau, Vincent Beyrand, Dennis F. A. E. Voeten, Vincent Fernandez, Paul Tafforeau, Koen Stein, Rinchen Barsbold, Khishigjav Tsogtbaatar, Philip John Currie, and Pascal Godefroit. The generic name combines a reference to the late Polish paleontologist Halszka Osmólska, who was involved in many expeditions to Mongolia and named the closely related Hulsanpes, with Latin raptor, "robber". The specific name honours Escuillié for having made the specimen available to science.[1]


Cretaceous-aged dinosaur fossil localities of Mongolia; Halszkaraptor fossils have been collected at the Ukhaa Tolgod locality
Skeletal diagram showing known remains. Scale bar equals 10 cm
Size compared to a human
Skull of holotype MPC D-102/109
Pectoral area of holotype MPC D-102/109
Pelvis area of holotype MPC D-102/109
Photo of the holotype at Munich Fossil Show in 2011 before the genus was named, labelled as a troodontid and with two rib fragments that are now lost
Reconstruction of Halszkaraptor escuilliei, with plumage and swimming posture based on aquatic birds that use wing-propelled swimming