The complete chloroplast genome sequence of Viola labradorica (Violaceae)

Viola labradorica is commonly known as Alpine violet, American dog violet, Dog violet, and Labrador violet. This species is distributed throughout eastern Canada and North America. In the present study, we sequenced the chloroplast genome of V. labradorica for the first time and performed a phylogenetic analysis of the genus Viola. The length of the chloroplast genome of V. labradorica was 158,751 bp. A large single-copy region (87,211 bp), a small single-copy region (17,344 bp), and two inverted repeat regions (27,098 bp each) were identified. A phylogenetic analysis was conducted using 77 protein-coding genes from the chloroplast genomes of 34 Viola. . Salix koriyanagi (Salicaceae) was used as an outgroup. The genus Viola forms a monophyletic clade. Among the clades for the genus Viola, , the sect. Viola formed a clade and was divided into two subclades: subsect. Viola and subsect. Rostratae. . Within the subsect. Rostratae, V. labradorica was placed in a basal position. These results contribute to a clear identification of the phylogenetic position of V. labradorica in the subsect. Rostratae.