During a review of the Blepharicera of western North America, we discovered a new species from several mid-sized rivers in southwestern Oregon and northwestern California. We hereby present descriptions of the larvae, pupae, and adults of B. kalmiopsis, new species. Diagnostic characters and a brief discussion of bionomics and distribution are also provided. Based on previous and ongoing studies, B. kalmiopsis clearly belongs to the B. micheneri Alexander species group and appears closely related to B. zionensis Alexander.