Position in a system
varietas
Penstemon fruticosus var. serratus (D.D. Keck) Cronquist
| system | Vitae - living organisms |
| domain | Eukaryota Whittaker & Margulis, 1978 - lifeforms with nucletic cells |
| superregnum | Bikonta - bikonts |
| Corticata | |
| Archaeplastida | |
| kingdom | Plantae Haeckel - plants |
| divisio | Magnoliophyta Cronquist, Takht. & W.Zimm. - flowering plants |
| class | Rosopsida Batsch - eudicots |
| order | Lamiales Bromhead |
| family | Plantaginaceae Juss. |
| genus | Penstemon Schmidel - beardtongue |
| species | Penstemon fruticosus (Pursh) Greene - Bush Penstemon |
| varietas | Penstemon fruticosus var. serratus (D.D. Keck) Cronquist |