Muilla is a genus with three species in the Androstephium-Muilla clade of the family Asparagaceae according to APGIII and Themidaceae according to APGII. They are native to the southwestern United States and northern Mexico, although all three species can be found in California. Plants grow from a corm and the small flowers are borne in an umbel.
Muilla coronata Greene is native to the desert regions of southeastern California and western Nevada. It is distinguished by filaments that are swollen at the base forming a crown with inflorescence 3–15 cm tall, and flowers 3–4 mm wide. The first two photos from iNaturalist taken by Jim Morefield in Mono County California in April and shared under a CC BY-NC license. The last photo taken outside the town of Joshua Tree, California by Kollibri terre Sonnenblume who has written a book on the wildflowers of Joshua Tree County.
Muilla maritima (Torr.) S.Watson ex Benth. grows in grassland, woodland and open scrub mostly in western California, the southeastern desert of California, south to Baja Mexico. The species can be distinguished from the rest by the thread-like filament that may only be swollen at the base. It blooms spring into summer. Flowers are small, white to greenish, striped brown. Anthers are blue-green or purple. The photos below were taken by Nhu Nguyen. Photo 1 was taken in March from Jepson Prairie Preserve, Solano Co, CA. Photos 2-4 were taken also in March from Anza-Borrego Desert State Park in southern California.
Photos 1-3 below were taken by Mary Sue Ittner of plants in cultivation. She wrote: "I collected seed of what I thought was an Allium along the Mendocino coast and when the plants were grown and it bloomed keyed it out to this genus and species that I didn't know grew where I lived. It was only in bloom for a few weeks and the flowers are small so it would be easily missed". Photos 4-5 were taken by Nhu Nguyen from the UC Botanical Garden of plants originating from Santa Clara Co., CA.
Muilla transmontana Greene is native to the desert regions of northeastern-central California and western Nevada (Great Basin Floristic Province). It is distinguished by filaments that are swollen at the base forming a crown with inflorescence 15–50 cm tall, and flowers 6–8 mm wide. Photos from iNaturalist taken by mtash in South Lake Tahoe in June and Jim Morefield in Indian Hills, Nevada, in May and shared under a CC BY-NC license.