This willow leaf beetle, Calligrapha verrucosa (Suffrian 1858) was found moving on the sand near a stream in Dinosaur Provincial Park, Alberta. They feed on the coyote willow (Salix exigua), whose habitat is best understood by its other common name, ‘Sandbar willow’. Calligrapha means ‘beautiful writing’ in Greek, in reference to the raised black markings (‘maculations’) on a pale background of the elytrawing covers.
C. verrucosa is highly variable in appearance (see images in the paper below}, and it can be confused with its near look-alike ‘cousin’, C. multipunctata. They are usually distinguishable, with C. verrucosa having a pale or bicolored pronotum (not completely dark) and elytronwing covers sutures that are paler than the maculations. If still in doubt, differences in the aedeagithe reproductive organ of male insects - the penis. can seal the ID¹.
Thanks to John Acorn for the ID and for the reference material.
¹Geographic variability in Calligrapha verrucosa (Suffrian 1858), a willow-feeding leaf beetle from western North America (Coleoptera: Chrysomelidae). MARK H. GOODMAN AND SHAWN M. CLARK. Insecta Mundi 2009(0092): September 25, 2009 (1-11)
(Image use from papers at Insecta Mundi is permitted under a Creative Commons Attribution-NonCommercial 3.0 Unported License.)