[3] Disa bracteata is naturalised in Western Australia, where the local name is "African weed-orchid.

Species that adapted to the same pollinator often independently evolved a similar floral morphology which confounded the infrageneric classification of Disa until cladistic analysis was applied to DNA sequences from this genus.

[11] The first molecular phylogeny of the genus involved comparison of nuclear ribosomal ITS1, 5.8S rDNA, and ITS2 sequences, and showed that Herschelia and Monadenia were nested within a paraphyletic Disa.

[12] In Genera Orchidacearum volume 2, Disa and Schizodium compose the subtribe Disinae of the tribe Diseae.

[13] After that volume was published in 2001, molecular phylogenetic studies showed that Schizodium is nested within Disa.

This version of Disinae is probably not monophyletic, but was created as a holding classification, to avoid the unnecessary designation of subtribes before further studies can clarify the relationships of these three genera.

Those with relatively large balloon-shaped seeds up to 1.5 mm long belong to the Disa uniflora group.

They belong to the few species in Orchidaceae that do not rely on mycorrhizal fungi for germination, and are thought to be an adaptation to hydrochory.