Solanum asterophorum

Gouvêa, Yuri & Stehmann, João, 2019, A Revision of the Solanum asterophorum Species Group (subg. Leptostemonum), Systematic Botany 44 (1), pp. 210-232 : 217

KEY TO THE SPECIES Of SOLANUM ASTEROPHORUM SPECIES GROUP

1. Major leaves entire (in mature plants), elliptic, the apex acuminate; stem prickles straight, sparsely distributed (less often with unarmed young stems); calyx cupuliform, usually densely covered with long-stalked trichomes; calyx lobes deltate........................... 3. Solanum piluliferum

1. Major leaves lobed, ovate to obovate, the apex acute to obtuse; stem prickles curved, moderately to densely distributed; calyx obconic, sparsely to densely covered with sessile to short-stalked trichomes; calyx lobes narrowly oblong, elliptic or lanceolate............................... 2

2. Pedicels notably curved downward and the flower buds pointing down; pedicel insertion points evenly and very closely spaced, usually overlapping......................................................................................... 1. Solanum asterophorum

2. Pedicels straight or nearly so, and the flower buds erect to spreading; pedicel insertion points more widely spaced proximally, if overlapping only on the more distal portion of the inflorescence.................................................................................. 3

3. Young stems and adaxial leaf surface completely covered by orange to ferruginous trichomes; branches horizontally spreading (plagiotropic); inflorescence axis unarmed............................................................................ 2. Solanum igniferum

3. Young stems and adaxial leaf surface covered by hyaline to brown-tinged trichomes; branches erect; inflorescence axis usually armed...................................................................................................... 4. Solanum sessilantherum