Also called : Guaymas Poreleaf, hierba del venado, maravilla
P.pausodynum, a less well known variety of slender poreleaf that was used by the Mexicans of Guaymas to alleviate headaches. (Johnson 1969).
Guaymas poreleaf is native to the semi-arid region of subtropical northern Mexico and is named after an historical port city in Sonora. Before European settlement this area was populated by the Guaymas, Seri and Yaqui peoples.

P.pausodynum can be a little more water sensitive than others in this species and may not be seen during dry seasons or years. (Felger etal 2016)

References
Robinson B.L. and Greenman J.M. (1896) A PROVISIONAL KEY TO THE SPECIES OF POROPHYLLUM, RANGING NORTH OF THE
ISTHMUS OF PANAMA : Contributions from the Gray Herbarium of Harvard University , 1896, No. 10