Mimulus mephiticus is a species of monkeyflower known by the common names skunky monkeyflower and foul odor monkeyflower. It has been reclassified as Mimulus nanus var. mephiticus. The species is native to the Sierra Nevada and western Great Basin of California and Nevada. Mimulus nanus var. mephiticus is a diminutive summer annual growing to a height of 15 cm (usually much smaller, especially at high elevation). The oppositely arranged leaves are linear or lance-shaped and up to 3 centimeters in length. The leaves emit an unpleasant scent when crushed, the characteristic that earned the plant its name. The trumpet-shaped flower may be up to 2 centimeters long and has an upper lip with two lobes and a lower lip with three. The flower is magenta or yellow, and populations occasionally have plants with both colors. The lower lip of the flower is marked with purplish lines and spots.