The identity of Grindelia angustifolia DC. ex Dunal (Asteraceae : Astereae)

A colored painting from the Sesse and Mocino expedition serves as the holot ype for the validly published name Grindelia angustifolia DC. ex Dunal, 181 9 (= Grindelia dunalii Sprengel, nom. nov., 1825; non Grindelia angustifoli a Kunth, in HBK, 1818). The illustration represents the species heretofore identified as Keerlia linearifolia DC., 1836 (= Gutierrezia alamanii A. Gra y, nom. nov., 1852; non Gutierrezia linearifolia Lagasca & Segura, 1816), w hich occurs in the south-central Mexican states of Mexico and Morelos. Guti errezia dunalii (Sprengel) Nesom, comb, nov., is proposed as the earliest v alid name for this species. Gutierrezia megalocephala (Fernald) Nesom is pr oposed for a closely related entity (Gutierrezia alamanii var. megalocephal a (Fernald) Lane = Xanthocephalum megalocephalum Fernald).