''Boreonykus'' is an extinct

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

dromaeosaurid Dromaeosauridae () is a family (biology), family of feathered coelurosaurian Theropoda, theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous period (geology), Period. The name Drom ...

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

, that lived during the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

in the area of present

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

. Fragmentary dromaeosaurid remains were discovered in the 1980s at the Pipestone Creek site in central

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

during excavations of a bonebed containing at least twenty-seven individuals of the ceratopsid '' Pachyrhinosaurus lakustai''. They were initially partly referred to a ''

Saurornitholestes ''Saurornitholestes'' ("lizard-bird thief") is a genus of carnivorous dromaeosaurid theropod dinosaur from the late Cretaceous of Canada (Alberta and Saskatchewan) and the United States (Montana, New Mexico, Alabama, and South Carolina). Two spe ...

'' sp in 2001. The

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

''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. The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

specimen of ''Boreonykus'', TMP 1989.055.0047, was found in a layer of the Wapiti Formation in central

, which dates from the late

Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...

, 73.27 ± 0.25 million years ago. It consists of a right

frontal bone In the human skull, the frontal bone or sincipital bone is an unpaired bone which consists of two portions.'' Gray's Anatomy'' (1918) These are the vertically oriented squamous part, and the horizontally oriented orbital part, making up the bo ...

. 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. A single

autapomorphy In phylogenetics, an autapomorphy is a distinctive feature, known as a Synapomorphy, derived trait, that is unique to a given taxon. That is, it is found only in one taxon, but not found in any others or Outgroup (cladistics), outgroup taxa, not ...

, 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. ''Boreonykus'' was, within the

Dromaeosauridae Dromaeosauridae () is a family of feathered coelurosaurian theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from ...

, placed in the Velociraptorinae. It was seen as both an indication of faunal provincialism and a quick species turn-over rate. However, in 2021, ''Boreonykus'' was recovered within the Dromaeosaurinae, restricting the distribution of velociraptorines only to Asia.

References

Eudromaeosauria Dinosaur genera Campanian dinosaurs Taxa named by Philip J. Currie Fossil taxa described in 2015 Dinosaurs of Canada {{theropod-stub