Penstemon ophianthus Pennell
Family: Plantaginaceae
Arizona Beardtongue,  more...
[Penstemon jamesii subsp. ophianthus (Pennell) Keck]
Penstemon ophianthus image
Freeman, in prep (draft for FNA vol. 17), Allred and Ivey 2012, Springer et al. 2008

Duration: Perennial

Nativity: Native

Lifeform: Forb/Herb

General: Perennial herb, 10-40 cm tall, from a branched woody caudex; stems 1 to 10 per plant, ascending to erect, sometimes glandular-pubescent and sometimes sparsely retrorsely puberulent near the base.

Leaves: Opposite along the stems, and also in a basal cluster; lower leaves on petioles and upper leaves usually sessile; blades linear to oblanceolate, 2-12 cm long and 2-22 mm wide, the edges smooth or with wavy teeth (sinuate-dentate), and the midvein sparsely retrorsely puberulent (with backward-pointing hairs).

Flowers: Purple and showy; arranged in narrow secund (one-sided) panicles, 6-20 cm long, at tops of stems; sepals 5 per flower, lanceolate, 6-9 mm long, glandular-pubescent; corolla 14-22 mm long, ventricose-ampliate (asymmetrically inflated) and 2-lipped, with the upper 2 lobes spreading to projecting (curving outward or not), and the lower 3 lobes spreading to reflexed (curving outward to downward); outside surface of corolla is glandular-pubescent, lavender to violet; inside of corolla is glandular-pubescent on the lower (abaxial) side, with dark purple nectar guide lines on both sides. Staminode (single sterile stamen) prominently exserted (sitcking out) from flower, with a recurved tip, the entire staminode covered with yellow hairs.

Fruits: Capsule 6-11 mm long, glabrous; splitting open longitudinally to release black angled seeds, 3-4 mm long.

Ecology: Found in sandy, gravelly, or clay soils in sagebrush shrublands, pinyon-juniper and oak woodlands, and ponderosa pine forests, from 4,500-7,500 ft (1372-2286 m); flowers May-June.

Distribution: AZ, NM, CO, UT

Notes: This purple-flowered Penstemon is most similar to P. jamesii, and indeed has been treated as a subspecies of that species. Distinguish between them based on flower size (corolla 14-22 mm long in P. ophianthus vs. 24-35 mm long in P. jamesii). While both species have asymmetrically inflated corollas, in P. jamesii the corolla is abrubtly constricted at the top of the throat, making the inflated portion of the corolla look more bladdery compared to P. ophianthus. Both species are characterized by the single sterile stamen (staminode) prominently sticking out of the flower, curling at the tip, and being covered by yellow hairs. In contrast, P. virgatus has a shorter, flat, non-hairy staminode. P. fendleri, another purple Penstemon, differs because it does not have an inflated corolla.

Ethnobotany: Unknown, but other species in the genus have uses.

Etymology: Penstemon comes from the Latin paene, nearly or almost, and Greek stemon, thread, alluding to the single sterile stamen within each flower; ophianthus comes from the Greek ophi, snake, and anthos, flower, alluding to the coiled staminode.

Synonyms: Penstemon jamesii subsp. ophianthus

Editor: AHazelton 2017