About Vulpicida canadensis (Räsänen) J.-E.Mattsson & M.J.Lai
Vulpicida canadensis has a leafy (foliose) thallus that is an intense yellow. It commonly produces apothecia, its sexual reproductive structures. Its asexual reproductive structures, called pycnidia, are embedded within the thallus and produce lemon-shaped (citriform) pycnoconidia. Like all other species in the genus Vulpicida, this lichen contains usnic acid in its cortex, and vulpinic acid plus pinastric acid in its medulla; these compounds are what give the thallus its characteristic yellow colour. Due to sharing a similar yellow colour, Vulpicida canadensis can be mistaken for Letharia columbiana. Unlike Vulpicida canadensis, Letharia columbiana is a shrubby (fruticose) lichen with a white medulla. Vulpicida canadensis is endemic to northwestern North America. It grows as an epiphyte on the bark and wood of conifer trees, and it often occurs alongside horsehair lichens from the genus Bryoria.
