Calycadenia oppositifolia is an annual herb that is native to California, and endemic (limited) to California.
California Rare Plant Rank: 4.2 (limited distribution).
[Wikipedia] Limited Range: It is native primarily to Butte County, California, although a few populations have been found in other parts of the state.[3] It grows in the foothills of the high mountain ranges. (link added by Mary Ann Machi)
Calflora:
Information on California plants for education, research and conservation,
with data contributed by
public and private institutions and individuals.
[web application]. 2025.The Calflora Database
[a non-profit organization].Available:
https://www.calflora.org/(Accessed: 03/28/2025).
one or more occurrences