Riverside Spineflower

Plants erect to infrequently spreading, (0.3-)0.5-2.5(-3) × 0.5-3(-5) dm, thinly pubescent. Leaves basal or nearly so; petiole 1-2(-3) cm; blade oblong or oblong-ovate to ovate, 0.3-1(-1.5) × 0.3-0.8(-1) cm, thinly pubescent adaxially, densely tomentose abaxially. Inflores-cences mostly flat-topped and openly branched, usually reddish; bracts persistent, 2, usually leaflike at proximal nodes and similar to proximal leaf blades only more reduced, short-petiolate, oblong-ovate to ovate, 0.3-0.8 cm × 2-6 mm, becoming sessile, reduced and scalelike at distal nodes, linear, acicular, often acerose, 0.1-0.4 cm × 0.5-1 mm, awns straight, 0.5-1 mm. Involucres in open clusters with 1 at node of dichotomies, reddish, cylindric, not ventricose, 3-4.5 mm, not corrugate, without scarious or membranous margins, thinly to densely pubescent; teeth spreading, unequal, 0.7-1.5 mm, 3 longer ones more erect than 3 shorter and less-prominent ones; awns uncinate, 0.5-1 mm. Flowers long-exserted; perianth rose to red, infrequently with white lobes, cylindric, 4.5-6 mm, pubescent; tepals connate ca. 2/ 3 their length, monomorphic to slightly dimorphic, narrowly oblanceolate, rounded apically, those of outer whorl occasionally slightly broader and longer than those of inner whorl; stamens 9, mostly included; filaments distinct, 4-6 mm, glabrous; anthers pink to red, oblong, 0.5-0.6 mm. Achenes brown, lenticular, 4-4.5 mm.