Linnaea 34: 147. 1865
Phenology: Flowering year-round.
Habitat: Desert scrub, sandy, rocky, calcareous soils.
Elevation: 0–1600 m.
Ariz., Calif., Nev., N.Mex., Tex., Mexico, Central America (Guatemala, Nicaragua).
Argythamnia serrata is widely distributed and variable; six species have been described to recognize this variation. However, these groups overlap morphologically and geographically, and many specimens cannot be determined with confidence. A broadly defined A. serrata is therefore recognized here.