 Acanthomintha duttonii

Acanthomintha duttonii is a species of annual plant endemic to San Mateo County, California in the family Lamiaceae.It is commonly called San Mateo thornmint or Dutton's acanthomintha and is found growing on serpentine soils near the Crystal Springs Reservoir in a six-mile (10 km) long strip on the east side of Montara Mountain at elevations of approximately 150 to 300 meters.