Penstemon albomarginatus is a member of subgenus Penstemon, section Penstemon, subsection Arenarii. There are two species in this subsection, both endemic to deep sand (the other species is P. arenarius). The common name for P. albomarginatus is White-margined Penstemon – the only Penstemon with white margins along the leaves.
This beautiful plant is endemic to the Mojave Desert, found in eastern California, southwestern Nevada, and northwestern Arizona. Despite being found in three states, the distribution is within about a 30 mile radius of Las Vegas, Nevada. There are fewer than 20 populations known and monitored, which makes it a species of concern despite it not yet being listed as Federally Threatened or Endangered.
My lab has been involved in a conservation genetics study as part of the RUMBA project, an NSF-sponsored program for undergraduate research involving biology and math students. The results have not yet been published, but we hope to remedy that in the coming months.
For more information about this interesting Penstemon, here are some links for further reading:
An environmental impact statement from Desert Renewable Energy Conservation Plan (development for solar energy is one of the main threats to the habitat).
Characterizing the ecology of the White-margined Penstemon (Powerpoint presentation by Stephen Zitzer).
Also, here are a few photos from my 2010 field season. I was able to collect from all known populations (many thanks to Stephen Zitzer from the Desert Research Institute!)