Domin, K. (1928), Beitrage zur Flora und Pflanzengeographie Australiens. Bibliotheca Botanica 22(89): 983 [comb. nov.]

basionym: Pigea banksiana Ging. ex DC. legitimate nomenclatural synonym: Ionidium banksianum (Ging. ex DC.) Steud. legitimate

Specht, R.L. in Specht, R.L. & Mountford, C.P. (ed.) (August 1958), The Gymnospermae and Angiospermae collected on the Arnhem Land Expedition. Records of the American-Australian Scientific Expedition to Arnhem Land No. 3 Botany and Plant Ecology: 261 [secondary reference]

taxonomic synonym: Ionidium suffruticosum (L.) Schult. legitimate

Chippendale, G.M. (17 April 1972), Check List of Northern Territory Plants. Proceedings of the Linnean Society of New South Wales 96(4): 249 [secondary reference]

Bennett, E.M. (14 November 1972), A revision of the Australian species of Hybanthus Jacquin (Violaceae). Nuytsia 1(3): 228 [taxonomic synonym]

taxonomic synonym of: Hybanthus enneaspermus (L.) F.Muell. subsp. enneaspermus legitimate

Jacobs, S.W.L. & Pickard, J. (1981), Plants of New South Wales: 210 [taxonomic synonym]

taxonomic synonym of: Hybanthus enneaspermus (L.) F.Muell. subsp. enneaspermus legitimate

Adams, L.G. & George, A.S. in George, A.S. (ed.) (1982), Violaceae. Flora of Australia 8: 103 [taxonomic synonym]

taxonomic synonym of: Hybanthus enneaspermus (L.) F.Muell. subsp. enneaspermus legitimate

Stanley, T.D. in Stanley, T.D. & Ross, E.M. (1986), Violaceae. Flora of South-eastern Queensland 2: 100 [taxonomic synonym]

taxonomic synonym of: Hybanthus enneaspermus (L.) F.Muell. subsp. enneaspermus legitimate

Council of Heads of Australasian Herbaria (2005), Australian Plant Census: - [taxonomic synonym]

taxonomic synonym of: Hybanthus enneaspermus (L.) F.Muell. legitimate

Council of Heads of Australasian Herbaria (2010), Australian Plant Census: - [taxonomic synonym]

taxonomic synonym of: Hybanthus enneaspermus (L.) F.Muell. legitimate

Forster, P.I. (24 March 2021), Reinstatement of Pigea Ging., an earlier generic name for the spade flowers previously included in Afrohybanthus Flicker (Violaceae). Austrobaileya 11: 30 [taxonomic synonym]

taxonomic synonym of: Pigea enneasperma (L.) P.I.Forst. legitimate

Council of Heads of Australasian Herbaria (7 July 2021), Australian Plant Census: - [taxonomic synonym]

taxonomic synonym of: Afrohybanthus enneaspermus (L.) Flicker legitimate

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