In 1747, the English naturalist
George Edwards included an illustration and a description of a female spruce grouse in the second volume of his
A Natural History of Uncommon Birds. He used the English name "The Brown and Spotted Heathcock". Edwards based his hand-coloured etching on a preserved specimen that had been sent to him in London from the
Hudson Bay in Canada by a Mr Light. Edwards was later sent what he assumed was a specimen of the male bird by
James Isham. In 1750, he included the male bird in the third volume of his book under the English name "The Black and Spotted Heathcock". When in 1758, the Swedish naturalist
Carl Linnaeus updated his
Systema Naturae for the
tenth edition, he placed the spruce grouse with other grouse in the
genus Tetrao. Linnaeus included a brief description, coined the
binomial name Tetrao canadensis and cited Edwards' work. The spruce grouse is now the only species placed in the genus
Canachites that was introduced in 1885 by the zoologist
Leonhard Stejneger. The genus name
Canachites combines the name
Canace from
Greek mythology with the
Ancient Greek -itēs meaning "resembling". In the first half of the 20th century, spruce grouse were classified as two separate species in the genus
Canachites: spruce grouse (
C. canadensis) and
Franklin's grouse (
C. franklinii), a position reinstated by Birdlife International in 2014. However, as of early 2021, the
International Ornithological Congress (IOC), the
American Ornithological Society, and the
Clements taxonomy retain Franklin's grouse as a subspecies of spruce grouse. The species was later moved to the genus
Dendragapus, congeneric with the
blue grouse with which spruce grouse often share coniferous habitats. However, spruce grouse do not have inflatable cervical sacs as in blue grouse, and the natal plumage of the two species is different. Based on its stronger resemblance to the
Siberian grouse (
Falcipennis falcipennis), the spruce grouse was later reclassified into the genus
Falcipennis. However, taxonomic studies found this classification to be
paraphyletic, with the Siberian grouse being
basal to a clade containing the spruce grouse,
Tetrao, and
Lyrurus. Due to this, the spruce grouse was again reclassified in
Canachites, bringing its taxonomy full-circle. The spruce grouse has six recognized subspecies: ==Description==