Penstemon barnebyi N.H.Holmgren
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Authority
Pavlik, Bruce M. & Barbour, Michael G. 1988. Demographic monitoring of endemic sand dune plants, Eureka Valley, California. Biol. Conserv. 46: 217-242.
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Family
Scrophulariaceae
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Scientific Name
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Type
TYPE: UNITED STATES. NEVADA. White Pine Co.: N end of White River Valley, 4.3 km (2.7 mi) up (W) White River road from U.S. Highway 6, 14.4 km (9 mi) airline distance W of Preston, T12N, R60E, S3, 1900 m (6250 ft) eleva- tion, among sagebrush in open pinyon-juniper country, 23 Jun 1977, N. & P. Holmgren 8492 (HOLOTYPE: NY; ISOTYPES: BRY, RENO, UTC, and others to be dis- tributed).
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Description
Latin Diagnosis - Foliis puberulis, staminodio exserto, corolla glanduloso-puberula, corollae faucibus ventre rotundatis, antherisque explanatis P. miserum A. Gray simulans, sed corolla minori 10-14 (nec 15-20 raro 14) mm longa, capsulisque minoribus 3-6 (nec 7-12 raro 6) mm longis diversa.
Species Description - Perennial herb with well developed basal leaves (mostly from short, sterile stems); flowering stems suberect to erect, 0.6-2 (3) dm tall, few to several clus- tered on a thick, sometimes branched caudex, surmounting a taproot; herbage re- trorsely-puberulent; leaves entire or obscurely toothed, 2-5.5 (7.5) cm long, 4-10 mm broad, the basal and lower cauline leaves lance-elliptic to spatulate, obtuse to rounded, petiolate, the upper cauline ones lanceolate, acute to obtuse, sessile; thyrse not secund, narrow, of 3-6 verticillasters, leafy, the cymes compressed, ca 3-5- flowered, the axis, peduncles and pedicels glandular-pubescent; sepals 4.5-7 cm long at anthesis, sometimes to 12 mm in fruit, linear-lanceolate to lanceolate, acute, glandular-pubescent, sometimes reddish-brown, the margins scarious proximally; corolla 10-13 (14) mm long, more or less abruptly ventricose-ampliate, the throat 4-5 mm broad (in pressed specimens), rounded ventrally, the tube 4-5 (6) mm long, strongly bilabiate, the upper lip projecting-arched, (3) 4-4.5 (5.5) mm long, the lobes of the lower lip reflexed, violet, the lobes blue towards the tips, the throat white within with red-violet guidelines and the tube yellowish, glandular-pubescent externally, the palate pale yellow to densely brownish-yellow bearded; staminode conspicuously exserted, coiled apically, densely orange-yellow bearded; fertile sta- mens included, the anther-sacs 0.7-0.9 mm long (after dehiscence), dehiscing the full length and becoming explanate, blue, essentially glabrous; capsule 3-6 mm long, broadly ovoid, acuminate; seeds ca 1.5-2.0 mm long.
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Discussion
(Fig. 5)
Alluvial gravels or silts derived from limestone, in sagebrush and pinyon-juniper communities, 1500-2500 m (5000-8200 ft) elevation. Endemic to east-central Nevada from the southern half of White Pine Co. to northern Lincoln Co. and northeastern Nye Co. (Fig. 4). Late May-June.
Penstemon barnebyi is a close relative of P. miser and P. janishiae, but because of its smaller flowers it more closely resembles P. concinnus Keck of the adjacent Bonneville Basin and P. atwoodii Welsh of the Kaiparowits Plateau. It is possible that these three small-flowered species have a common ancestor which became frag- mented during the climatic shifts of the Pleistocene.
Nearly fourteen years ago, while discussing the Intermountain flora with me, Rupert C. Barneby pointed out some of the dissimilarities between this small- flowered Penstemon of limestone alluvial soils and the large-flowered one on weath- ered volcanic soils to the west (P. janishiae). The results of the present study confirm his observations. It gives me great pleasure to name this species after him in commemoration of the many such enlightening discussions on the western floras. His vast knowledge, intellect, enthusiasm, insatiable curiosity, boundless energy and keen sense of humor have been a constant source of inspiration and help to me.