Thelypodium integrifolium var. longicarpum (Al-Shehbaz) N. H. Holmgren

Racemes (moderately to strongly congested), not elongated in fruit; central rachis (4.3-)8-20 cm. Fruiting pedicels usually horizontal to reflexed, rarely divaricate, straight, whitish, stout, (6-)7-11(-13) mm, strongly flattened at base. Flowers: petals white, (7.5-)8-11(-13) mm; gynophore stout, (1-)1.5-4(-5.5) mm. Fruits usually horizontal to reflexed, rarely divaricate, straight or incurved to arcuate, (2.2-)3.5-6.5(-8) cm.

Flowering Aug-Oct. Canyons, shrub communities; of conservation concern; 500-1300 m; Ariz.

Subspecies longicarpum is known from the Grand Canyon National Park and adjacent canyons of the Colorado River.