In his Flora Franciscana (Greene, 1891) he placed this unique species in a special group of the genus Streptanthus characterized by "Calyx very irregular, the uppermost sepal greatly enlarged, in aestivation conduplicate
over the others".
In the plantlets, cotyledons unfold from a conduplicate
6 cm, not basally constricted, linear, usually conduplicate
, pubescent on both surfaces, rarely glabrous, margins scabrous towards the apex, acute apex; ligule 0.
suberosus have a conduplicate
blade that leaves only the abaxial face exposed, which seems to explain the distribution pattern of the glandular trichomes in those organs.
6-4 mm, thinly chartaceous, hirsute, the inner ones foliar, elliptic-lanceolate, hirsutulous, usually slightly smaller than the outer series; receptacle minute, paleate, the pales lanceolate, conduplicate
5 to 15 mm wide, green, clothed by 4 triangular to narrowly triangular sheaths, acute to acuminate, scarious-papyraceous, lacking a foliar blade, deciduous; leaf solitary, at the apex of the mature pseudobulb, conduplicate
, oblong to oblong-elliptic, acute, fleshy, 6 to 29 cm long, ca.
2 cm the largest one), concolorous with the petals, a white, conduplicate
spiral stigma in an elongated, white style 6.
variegatifolia; the leaves are concolorous, green, ovate to ovate-lanceolate in outline, usually conduplicate
along their midrib with epicuticular wax over a striated or folded epidermis.