Mueller, F.J.H. von (1866), Fragmenta Phytographiae Australiae 5(40): 202 [tax. nov.]

• Type: Helmholtzia acorifolia F.Muell.

Mueller, F.J.H. von (1882), Systematic Census of Australian Plants: 122 [secondary reference]

Baillon, H.E. (1895), Histoire des Plantes 13: 234 [basionym]

basionym of: Philydrum sect. Helmholtzia (F.Muell.) Baill. legitimate

Dixon, W.A. (1906), The Plants of New South Wales: 277 [secondary reference]

Skottsberg, C.J.F. (December 1948), Philydraceae. Flora Malesiana Series I 4(1): 5 [secondary reference]

Evans, O.D. & Johnson, L.A.S. (1966), Philydraceae. Contributions from the New South Wales National Herbarium, Flora Series 31: 5-6 [secondary reference]

Hamann, U. (1966), Willdenowia Beihefte: 155-157 [secondary reference]

Cronquist, A.J. (1981), An Integrated System of Classification of Flowering Plants: 1201 [secondary reference]

Jacobs, S.W.L. & Pickard, J. (1981), Plants of New South Wales: 35 [secondary reference]

Adams, L.G. in George, A.S. (ed.) (1987), Philydraceae. Flora of Australia 45: 44-46 [secondary reference]

nomenclatural synonym: Philydrum sect. Helmholtzia (F.Muell.) Baill. legitimate taxonomic synonym: Orthothylax (Hook.f.) Skottsb. legitimate

• APC Dist.: Qld, NSW

Stanley, T.D. in Stanley, T.D. & Ross, E.M. (1989), Philydraceae. Flora of South-eastern Queensland 3: 61 [secondary reference]

Brummitt, R.K. (1992), Vascular Plant Families and Genera: 307 [secondary reference]

taxonomic synonym: Orthothylax (Hook.f.) Skottsb. legitimate

Jacobs, S.W.L. in Harden, G.J. (ed.) (1993), Philydraceae. Flora of New South Wales 4: 251 [secondary reference]

Hamann, U. in Kubitzki, K. (ed.) (1998), Philydraceae. The Families and Genera of Vascular Plants 4: 393 [secondary reference]

Cooper, W.E. & Cooper, W.T. (2004), Fruits of the Australian Tropical Rainforest: 395 [secondary reference]

Mabberley, D.J. (1 May 2008), Mabberley's Plant-Book Edn. 3: 398 [secondary reference]

Council of Heads of Australasian Herbaria (7 July 2021), Australian Plant Census: - APC [secondary reference]

nomenclatural synonym: Philydrum sect. Helmholtzia (F.Muell.) Baill. legitimate taxonomic synonym: Philydrum subg. Orthothylax Hook.f. nom. alt. taxonomic synonym: Philydrum sect. Orthothylax Hook.f. nom. alt. taxonomic synonym: Orthothylax (Hook.f.) Skottsb. legitimate

• APC Dist.: Qld, NSW

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