Calochortus excavatus is a species of flowering plant in the lily family known by the common name Inyo County star-tulip. The flowering plant is endemic to eastern California, where it is known from several reduced and threatened populations in Mono and Inyo Counties. It occupies grassy habitats in alkaline Shadscale scrub plant communities, alongside Atriplex and other playa halophyte flora, primarily in Owens Valley. The species is listed as endangered, threatened by the loss of local groundwater. Calochortus excavatus is a perennial bulb, growing a slender unbranched stem to about 30 centimetres (12 in) in maximum height. The inflorescence bears 1 to 6 erect bell-shaped flowers in a close cluster. Each flower has three sepals which lack spotting, and three white petals. The petals may have green striping on their outer surfaces and generally have a red-purple blotch at the base. The anthers are reddish to purple.