Halszkaraptorinae
Halszkaraptorinae is a basal subfamily of Dromaeosauridae that includes the enigmatic genera Halszkaraptor, Mahakala, and Hulsanpes. A comparison of the fossils of Halszkaraptor with the bones of extant crocodilians and aquatic birds revealed evidence of a semiaquatic lifestyle. The group is named after Polish paleontologist Halszka Osmólska.Description
Halszkaraptorinae is defined as the most inclusive clade that contains Halszkaraptor escuilliei but not Dromaeosaurus albertensis, Unenlagia comahuensis, Saurornithoides mongoliensis or Vultur gryphus. The subfamily is diagnosed by their long necks, proximal caudal vertebrae with oriented articular processes and prominent zygodiapophyseal laminae, a flattened ulna with a sharp posterior margin, ilium with a shelf-like supratrochanteric process, metacarpal III shaft transversely as thick as that of metacarpal II, a posterodistal surface on the femoral shaft with an elongate fossa bound by a lateral crest and the proximal half of metatarsal III being unconstricted and markedly convex
anteriorly.Classification
The cladogram below is based on the phylogenetic analysis conducted in 2017 by Cau et al. using updated data from the Theropod Working Group in their description of Halszkaraptor.
