Erect, densely foliate shrublet ±3-6 dm tall with terete long-shoots, the growing tips and lf-axes thinly minutely puberulent and minutely granular, the small crowded lfts bicolored, facially glabrous ciliate, adaxially dark and ± lustrous, the few-fld umbelliform capitula slenderly pedunculate in coeval lf-axils; phyllotaxy distichous. Stipules linear-lanceolate or narrowly subulate ±2-3.5 x 0.5 mm, tardily deciduous. Lf-formula iv-vii/25-29; lf-stk of primary lvs ±2-5 cm, the petiole 6-12 mm, at middle 0.6-0.9 mm diam, the ventral groove bridged at insertion of pinnae, the longer interpinnal segments 5-7 mm; pinnae distally subaccrescent, the furthest or the penultimate pair longest, their rachises 2.2-4.5 cm, the longer interfoliolar segments 1-1.8 mm; lft-pulvinules at most 0.3 x 0.4 mm, not wrinkled, the blades sessile against the rachis; lft-blades decrescent only at very ends of rachis, semi-ovate from short obtuse auricle, slightly curved upward, acute, those near mid-rachis ±3.5-5 x 1.1-1.4 mm, 3-3.5 times as long as wide; venation indistinct, the midrib displaced to divide blade ±1:2, faintly 1-2-branched at or beyond middle, the one posterior primary nerve sometimes immersed, when visible incurved-ascending to mid-blade at furthest. Peduncles ±3-4.5 cm, ebracteate; capitula 3-6-fld, the receptacle 0.5-1 mm; bracts ovate 0.4-1 mm, deciduous; fls homomorphic; pedicels 2.5—4 x 0.5 mm; perianth 5-merous, reddish, remotely strigulose and charged with a few minute, amorphously pluri- cellular trichomes, the calyx weakly 5-nerved, the corolla externally nerveless, its lobes granular- ciliolate; calyx shallowly campanulate ±1.2-1.7 mm, the deltate teeth ±0.6 mm; corolla ±4.5 mm, cleft to middle, the lance-ovate lobes spreading-recurved; androecium red-pink, 18- or 32-merous in 2 dissected fls, ±2 cm, the tube ±2 mm, the stemonozone ±1 mm; ovary at anthesis glabrous, surrounded by a lobed disc 0.55 mm. Pods erect, in broad profile ±4.5-6.5 x 0.6 cm, the sutural ribs in dorsal view nearly 2 mm wide, the brown, stiffly chartaceous valves weakly randomly nerved, subappressed-puberulent overall; seeds (1 seen fully ripe) 6.2 x 3.2 mm, the testa smooth fuscous, pleurogrammic.

In open places on steep mountainsides in dry oak- pine forest, 1900-2000 m, known only from the type- locality, near 20°20'N, 104°30'W in s.-w. Jalisco, Mexico. — Fl. IX-X.