Monographs Details: Psorothamnus kingii (S.Watson) Barneby
Authors:Rupert C. Barneby
Authority: Barneby, Rupert C. 1977. Daleae Imagines, an illustrated revision of Errazurizia Philippi, Psorothamnus Rydberg, Marine Liebmann, and Dalea Lucanus emen. Barneby, including all species of Leguminosae tribe Amorpheae Borissova ever referred to Dalea. Mem. New York Bot. Gard. 27: 1-892.
Family:Fabaceae
Synonyms:Dalea kingii S.Watson, Parosela kingii (S.Watson) A.Heller
Description:Species Description - Subherbaceous, low and diffuse, the stems arising singly from buds on widely creeping reddish cordlike stolons running at a depth of 1-10 cm below level of the sand ± pilosulous with straight, narrowly ascending and subappressed white hairs up to 0.5-0.8 mm long, the lower stem and early leaves thinly so or sometimes glabrous bright yellow-green, the leaflets of upper leaves densely pubescent, canescent above greener and gland-punctate beneath; stems above ground 1-3.5 dm long, at almost every node divaricately branched, becoming stiff, pustulate with yellow glands, the distal branchlets and raceme-axes modified into tapering, yellow-pointed spines 1-(3.5) cm long; leaf-spurs up to 1 mm long; stipules ± dimorphic, those subtending leaves subherbaceous becoming papery and yellowish, narrowly subulate to linear attenuate, (1) 1.5-5 mm long, subglabrous, but some low on the stem broadly oblanceolate, up to 1 cm long, coarsely 1-3-dentate; leaves 1-4.5 cm long, short-petioled with margins, pustular rachis and 1-4 (the main cauline leaves with 2-4, the upper ones with 1-2) pairs of ovate to rhombic-ovate or oblong-elliptic, stoutly yellow mucronate leaflets (3) 5-12 (15) mm long, their margins thickened, subrevolute, entire to obscurely undulate or rarely dentate; racemes sessile or almost so, loosely 1- (5)-flowered, the first flower borne at or just above base, the axis running out into glabrous yellow spinule; bracts resembling stipules, 1.5-2.5 mm long; pedicels slender 1-2.3 mm long, charged at apex with a pair of bracteoles 0.6-2.3 mm long, often accompanied by a pair of glands; calyx 7-8.2 mm long, thinly strigulose-pilosulous externally, the inner face of the teeth silky-canescent, the disc 1-1.5 mm deep, the vase-shaped tube 3.8-4.2 mm long, herbaceous throughout but the intervals a little thinner than the inconspicuous ribs and charged with 1 row of 2-7 glands of varying sizes, the teeth unequal, the ventral pair (united no higher than the rest) ovate, acute, 3-4.2 mm long, 1.8-2.6 mm wide, about twice wider and a little longer than the lanceolate lateral and dorsal ones; petals glabrous, blue, the banner charged with a large subapical gland, the keel and often the wings glandless; banner 7-9.2 mm long, obovate- cuneate, deeply notched, the blade 5.2-7.4 mm wide, evenly curved backward, tapering downward into the scarcely differentiated claw; wings as long or a trifle longer, 7.8-9.3 mm long, the claw 3-3.6 mm, the oblong, obtuse or obliquely emarginate blade 5-6.6 mm long, 3.2-3.9 mm wide; keel 8-10 mm long, the claw 3-3.8 mm, the broadly obovate blade 5.2-6.5 mm long, 3.4-4 mm wide; androecium 8-9.5 mm long, the filaments free for 3.2-4.4 mm, the anthers 0.8-1.5 mm long; pod in profile obliquely, rather narrowly obovate in outline, (3.5) 4-5.5 mm long, the style-base lateral slightly below apex, the valves in the lower half hyaline, glabrous, distally papery, pilosulous, sprinkled with small, pale yellow glands; seeds 1 or 2, when 2 one raised obliquely beyond the other, 3.1-3.8 mm long, 2.1-2.5 mm diam, pallidly olivaceous with a linear brown patch extending from scar half way to base; 2n = 20 (Mosquin). — Collections: 11 (i).

Distribution - Sandbanks and hollows of hummocked dunes, ± 1300-1400 m (4350-4700 ft), forming extensive colonies but extremely local, known by modern collections only from the great dunes in the piedmont of Santa Rosa Mts. on the w. bank of Little Humboldt River (Paradise Valley) and from s. end of Silver State Valley at points 8-20 mi n.-w. of Winnemucca, Humboldt County, Nevada, but described from Hot Springs Mts, s.-w. of Brady’s Hot Springs in Carson Sink, n.-w. Churchill County ± 180 km s.-w. of Paradise Valley), to be sought elsewhere in lower Humboldt River Valley.-Flowering June to August, in fruit July to September.

Discussion:

(Plate III)

Distribution:United States of America North America| Nevada United States of America North America|

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