Penstemon
laetus
var.
leptosepalus
Greene ex A. Gray
Synonyms
Penstemon
laetus
subsp.
leptosepalus
(Greene ex A. Gray) D.D. Keck
Flora of North America Editorial Committee. 2019. Magnoliophyta: Tetrachondraceae to Orobanchaceae. 17: i–xxiv, 1–737. In Flora of North America Editorial Committee (eds.)
Fl. N. Amer.
. Oxford University Press, New York.