Clarkia mosquinii is a rare species of flowering plant in the evening primrose family known by the common name Mosquin's clarkia.

It is endemic to California, where it is known only from the northern Sierra Nevada foothills at the border between Butte and Plumas Counties.

[2] It is an erect annual herb often exceeding half a meter in height.

The oval or lance-shaped leaves are 2 to 5 centimeters long.

The diamond-shaped petals are one to two centimeters long light to medium purple in color, and sometimes speckled with reddish purple.