Penstemon scariosus is a species of flowering plant in the plantain family known by the common name White River beardtongue. It is native to Colorado, Utah, and Wyoming in the United States.[1]
There are four varieties of this species, including var. albifluvis (White River beardtongue), var. cyanomontanus (Neese's Blue Mountain beardtongue), and var. garrettii (Garrett's beardtongue).[2] The var. albifluvis is a rare variety limited to northeastern Utah and northwestern Colorado. It is up to 30 centimeters tall and produces lavender or light blue flowers.[3] The flowers are pollinated by bees.[4] This variety is a candidate for federal protection because it grows on oil shale, a common source of petroleum.[5]