Brodiaea filifolia, known by the common name thread-leaved brodiaea, is a rare species of flowering plant in the cluster-lily genus. It is endemic to southern California, mostly in the region around the junction of Orange, Riverside, and San Diego Counties.

The bulb is a resident of scattered remaining vernal pool and grassland habitats. It is a federally listed threatened species and it has been listed as an endangered species since 1982 on the state level.

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