Dorn’s twinpod

Perennials; (compact); caudex simple, (stout); densely (silvery) pubescent throughout (except style), trichomes several-rayed, rays furcate, fused at base, (umbonate, tuberculate through-out). Stems simple from base, erect, (arising from a condensed rosette), to 1 dm. Basal leaves (ascending or erect); blade elliptic to oblanceolate to obovate, (usually curled from middle to apex), (1.5-) 5-7 cm (width 12-20 mm), margins entire. Cauline leaves (1-5); blade oblanceolate, 1-2.5 cm, margins entire. Racemes compact (or elongated in fruit, to 1 dm, barely exceeding leaves). Fruiting pedicels (divaricate-ascending, slightly curved), 7-18 mm. Flowers: sepals (erect), oblong to linear or spatulate, 5.5-7 mm; petals spatulate, 10-14 mm, (claw undifferentiated from blade). Fruits didymous, irregular, highly inflated, 8-11(-18) × 10-15 mm, (papery, basal sinus shallower than the deep apical sinus; valves retaining seeds after dehiscence); replum obovate, not constricted, 1-1.8 mm, apex obtuse, as wide as or wider than fruit; ovules (4-)8(-12) per ovary; style 4-6 mm, (glabrous). Seeds flattened, (oblong to elliptic, thin-margined or not).

Flowering May-Jun. Calcareous shale, slopes, ridges; of conservation concern; 1900-2200 m; Wyo.