Syn. : Anthemis valentina, Porophyllum macrocephalum DC. var. leiocarpum Urb.

Also called : yerba de peo

Porophyllum macrocephalum and Bifora testiculata have also been called yerba de peo.

P.leiocarpum is native to the region of Puerto Rico and can also be found in the Dominican Republic, Venezuela, and Brazil. This plant is considered an “invasive” in Venezuela. (Rodrigo etal 2007)

In the Monograph of the Plant Genus Porophyllum (Johnson 1969) P.leiocarpum is noted thusly,

“This entity is retained as a species rather than as a variety of P. macrocephalum. Specimens from Puerto Rico show no signs of intergradation or hybridization of P. leiocarpum with P. ruderale subsp. ruderale, which occurs in the same area. Furthermore, there is no indication of hybridization with P. ruderale subsp. macrocephalum on the South American mainland where both P. leiocarpum and macrocephalum occur.”

Porophyllum leiocarpum was originally described as a variety of P.macrocephalum but was elevated to specific status by Rydberg and has been treated as such by subsequent authors (Hansen 2012).

This variety (as is typical of the species) is described as “ill smelling” (Liogier 1985)

• Debra R. Hansen, Robert K. Jansen, Rowan F. Sage, José Luis Villaseñor, Beryl B. Simpson “Molecular Phylogeny of Pectis (Tageteae, Asteraceae), a C4 Genus of the Neotropics, and its Sister Genus Porophyllum,” Lundellia, 19(1), 6-38, (1 December 2016)
• Johnson, Roy.R. : Monograph of the Plant Genus Porophyllum (Compositae: Helenieae) : The University of Kansas Science Bulletin : Vol XLVII : No 7. Jan 31, 1969
• Liogier, A. H. (1985). Descriptive flora of Puerto Rico and adjacent islands: Spermatophyta. 1a ed. Río Piedras, P.R.: Editorial de la Universidad de Puerto Rico.
• S, Rodrigo & Aymard, Gerardo & Huber, Oo. (2007). Catálogo anotado e ilustrado de la ora vascularde los llanos de Venezuela