Mimulus exiguus is a rare species of monkeyflower known by the common name San Bernardino Mountains monkeyflower. It is native to the San Bernardino Mountains of southern California, as well as an area of Baja California. It grows in moist, rocky habitat, including the rare quartz pebble plain habitat of the mountain meadows near Big Bear, Southern California. It is native to the San Bernardino Mountains of southern California, as well as an area of Baja California. It grows in moist, rocky habitat, including the rare quartz pebble plain habitat of the mountain meadows near Big Bear, Southern California. Mimulus exiguus is a petite annual herb producing a hair-thin, erect stem just a few centimeters tall. The herbage is reddish in color and lightly hairy. The oppositely arranged oval leaves are a few millimeters in length. The tubular lavender flower is under 4 millimeters long and the corolla is divided into five lobes.