syn Porophyllum scoparium
also called Hierba del venado, jarilla, romerillo (1) (Coahuila)
- Romerillo is also the common name for Bidens pilosa (which is also called black-jack, beggarticks, hairy beggarticks, cobbler’s pegs, devil’s needles, Spanish needle, shepherds needles, farmers friend, Devils Pitchfork, sticky beaks, toothache plant)

Porophyllum X fruticulosum Rydb. was first proposed in 1916 as a species, typified by a specimen collected by Palmer near Saltillo, Mexico. The species was subsequently treated as a natural hybrid between the relatively localized P. amplexicaule and the more abundant and widespread P. scoparium
This plant is one of the more common roadside weeds throughout much of its range.
Other plants identified as Romerillo are….
Tridax procumbens Bidens pilosa
Hypericum laricifolium Asclepias linaria
Eupatorium buniifolium Hymenoclea monogyra
References
- Johnson, Roy.R. : Monograph of the Plant Genus Porophyllum (Compositae: Helenieae) : The University of Kansas Science Bulletin : Vol XLVII : No 7. Jan 31, 1969
- Turner, B.L. 2013. Taxonomic status of Porophyllum X fruticulosum Rydb. (Asteraceae: Tageteae). Phytoneuron : ISSN 2153 733X