Subspecies, varieties, forms and cultivars of plants belonging to the Arrojadoa dinae group

Arrojadoa dinae, Arrojadoa multiflora, Arrojadoa eriocaulis and Arrojadoa beateae are a group of distinct but related species in Minas Gerais and Bahia. They are readily distinguished by their subterranean tubers, stems, wood anatomy, bi-colored flowers, and fruits. Most authors regard them as conspecific under the oldest name Arrojadoa dinae. However some studies in the field, show that it should be better to maintain these taxa as separate species. In some cases they even grow together (A. dinae, A. eriocaulis) without hybridization.

• Arrojadoa beateae P.J.Braun & Esteves
• Arrojadoa dinae Buining & Bredero: (subsp. dinae) has stems up to 30 cm tall, usually with 11 ribs, whitish spines, and brownish carmine flowers with yellow interiors. Distribution: Bahia.
• Arrojadoa dinae subs. eriocaulis (Buining & Bredero) N.P.Taylor & Zappi: typically has 8-9 ribs, yellowish brown spines, and light violet-pink flowers. Distribution: Minas Gerais.
• Arrojadoa dinae var. nana P.J.Braun & Esteves: this is a smallish form strictly related to Arrojadoa dinae subs. eriocaulis.
• Arrojadoa eriocaulis var. rosenbergeriana Van Heek & W.Strecker: Distribution: East of Mato Verde, Minas Gerais, Brazil.
• Arrojadoa multiflora F.Ritter: has stems, up to 80 cm tall. Ribs 7-8. Flowers inside pale yellowish , outside somewhat ruby. Distribution: Bahia.