Pityopsis graminifolia var. latifolia

Pityopsis graminifolia (Michx.) Small var. latifolia (Fern.) Semple is a  morphologically variable race.  It is widely distributed throughout much of the range of the species and in disjunct locations in Guatemala and adjacent Mexico and Honduras in Central America.  It usually has large basal rosette leaves that range from very narrow (P. nervosa morph) to broad. The variety is mostly tetraploid (2n=36), but some hexaploid (2n=54) populations occur in northern Alabama and eastern Tennessee. See Semple (2006 FNA). Nesom (2019) treated it as P. latifolia restricted to central Florida.and cited Bridges and Orzell (2018, p. 28). Nesom (2019) illustrated Semple 10904 USF as P. tracyi which I had treated as var. latifolia. He stated that narrowly defined species is characterized by its "well developed rosette of spreading to somewhat ascending, broadly strap-like basal leaves, typically over 2 cm wide, and its reduced, clasping cauline leaves."  Both multivariate morphometric and polygenomic DNA studies involving many samples over the range of P. graminifolia is needed to hopefully provide support for either species or variety rank.

The diversity of morphs within the variety is reflected in the multiple names placed in synonymy and in the long history of being placed in multiple genera: Chrysopsis graminifolia (Michaux) Elliott var. latifolia Fernald; C. argentea (Persoon) Elliott; C. correllii Fernald; C. latifolia (Fernald) Small; C. nervosa (Willdenow) Fernald; C. nervosa var. stenolepis Fernald; C. nervosa var. virgata Fernald; Diplopappus sericeus Hooker; Erigeron nervosus Willdenow; Heterotheca correllii (Fernald) H. E. Ahles; H. nervosa (Willdenow) Shinners; Heyfeldera sericea Schultz-Bipontinus; Inula argentea Persoon; Pityopsis argentea (Persoon) Nuttall; P. nervosa (Willdenow) Dress.

Last revised 20 April 2025 by J.C. Semple

© 2025 J.C. Semple, including all photographs unless otherwise indicated