''Penstemon thompsoniae'', Thompson's beardtongue, is a low perennial plant

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the southwestern United States, where it grows in dry shrublands, woodlands and forests. It is considered a species of conservation concern in California.

Taxonomy

''Penstemon thompsoniae'' originally was considered a variety of ''Penstemon pumilis'', as published by

Asa Gray Asa Gray (November 18, 1810 – January 30, 1888) is considered the most important American botany, botanist of the 19th century. His ''Darwiniana'' (1876) was considered an important explanation of how religion and science were not necessaril ...

in 1878. It was later reclassified as ''Penstemon caespitosus'' var. ''thompsoniae'' by

Aven Nelson Aven Nelson (March 24, 1859 – March 31, 1952) was an American botanist who specialized in plants of the Rocky Mountains. He was one of the founding professors of the University of Wyoming, where he taught for 55 years as professor and served as ...

, and then elevated to full species by

Per Axel Rydberg Per Axel Rydberg (July 6, 1860 – July 25, 1931) was a Swedish-born, American botanist who was the first curator of the New York Botanical Garden Herbarium. Biography Per Axel Rydberg was born in Odh, Västergötland, Sweden and emigrated to ...

. In 1937, David D. Keck recognized two subspecies of ''Penstemon thompsoniae'': ssp. ''jaegeri'', restricted to mountains of Clark County, Nevada, which he distinguished by its few, remote stems and open

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

, and ssp. ''thompsoniae'' in Arizona, Nevada, and Utah, which he distinguished by its tufted stems and compact inflorescences. These subspecies are no longer recognized due to the morphologic continuum that exists between them.thompsoniae'' in Flora of North America
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Description

''Penstemon thompsoniae'' is a mat-forming perennial herb or subshrub, less than 15 cm high, with a woody base. It is ashy gray-green with a thick coating of hairs. The leaves are oval or spoon-shaped, to 2 cm long. The short

bears wide-mouthed tubular purple flowers to 2 cm long, glandular hairy on the outer surface, and somewhat hairy on the inner. The tip of the

staminode In botany, a staminode is an often rudimentary, sterile or abortive stamen, which means that it does not produce pollen.Jackson, Benjamin, Daydon; ''A Glossary of Botanic Terms with their Derivation and Accent''; Published by Gerald Duckworth & Co ...

is covered in yellow to orange hairs.

Distribution

''Penstemon thompsoniae'' is endemic to the southwestern United States, occurring in Nevada, southwest Utah, Arizona and southeastern California. Habitat includes sandy to gravelly soils, sagebrush shrublands, pine-juniper woodlands and pine forests, at 1500–3400 m elevation. It typically blooms May–Aug. The limited range of ''Penstemon thompsoniae'' in California has made it of state conservation concern.

History

''Penstemon thompsoniae'' was first collected by

Ellen Powell Thompson Ellen Louella (Nellie) Powell Thompson (1840–1911) was an American naturalist and botanist, and an active advocate for women's suffrage. Life Ellen Louella (Nellie) Powell was born in Ohio to parents of English origin. Her siblings included ...

in 1872 in the vicinity of Kanab, Utah, during the US Topographical and Geological Survey of the Colorado River (led by

John Wesley Powell John Wesley Powell (March 24, 1834 – September 23, 1902) was an American geologist, U.S. Army soldier, explorer of the American West, professor at Illinois Wesleyan University, and director of major scientific and cultural institutions. He ...

). Her specimen, the

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

, is deposited at the Gray Herbarium.

Cultivation

Although it is sometimes grown in rock gardens, ''Penstemon thompsoniae'' is more sensitive to moisture than

Penstemon caespitosus ''Penstemon caespitosus'', commonly known as mat penstemon, is a summer blooming perennial flower in the large ''Penstemon'' genus. It is a widespread plant from near timberline to the foothills in the Southern Rocky Mountains and Colorado Plate ...

and outside its native habitat it is better in specialized cultivation situations like an Alpine house.

References

External links

Jepson Manual TreatmentPhoto gallery
{{Taxonbar, from=Q7164894 thompsoniae Flora of the Southwestern United States