Boreonykus

Boreonykus is an extinct genus of dromaeosaurid dinosaur, that lived during the Late Cretaceous in the area of present Canada.

Boreonykus Temporal range: Late Cretaceous, ~
Restoration
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Clade:	Theropoda
Family:	†Dromaeosauridae
Clade:	†Eudromaeosauria
Subfamily:	†Velociraptorinae
Genus:	†Boreonykus Bell & Currie, 2015
Type species
†Boreonykus certekorum Bell & Currie, 2015

Fragmentary dromaeosaurid remains were discovered in the eighties at the Pipestone Creek site in central Alberta during excavations of a bonebed containing at least twenty-seven individuals of the ceratopsid Pachyrhinosaurus lakustai.[1] They were initially partly referred to a Saurornitholestes sp in 2001.[2]

The type species Boreonykus certekorum was named and described by Phil Bell and Philip John Currie in 2015. The genus name is a variation of "Boreonychus", "northern claw". The specific name certekorum references the Certek company, that works in the oil industry and provided financial support for the excavations.[1]

The holotype specimen of Boreonykus, TMP 1989.055.0047, was found in a layer of the Wapiti Formation in central Alberta, which dates from the late Campanian, 73.27 ± 0.25 million years ago. It consists of a right frontal bone. Fourteen loose teeth have been referred to the species, as well as several postcranial bones, perhaps of the same individual: the specimen TMP 1988.055.0129, a rear caudal vertebra; UALVP 53597, a claw of the second finger, and the specimen TMP 1986.055.0184.1, a sickle claw of the foot.[1]

A single autapomorphy, unique derived trait, was indicated: the ridges bordering the fronts of the depressions around the supratemporal fenestrae form an acute angle of 55° together, pointing to the rear.[1]

Boreonykus was, within the Dromaeosauridae, placed in the Velociraptorinae. It was seen as both an indication of faunal provincialism and a quick species turn-over rate.[1]