Fenzl, E. in Endlicher, S.F.L., Fenzl, E., Bentham, G. & Schott, H.W. (April 1837), Rhamneae. Enumeratio plantarum quas in Novae Hollandiae ora austro-occidentali ad fluvium Cygnorum et in Sinu Regis Georgii collegit Carolus liber baro de Hügel: 25 [nom. nov.]

replaced synonym: Ceanothus spatulatus Labill. legitimate

• Comment: The designation “Trymalium billardierei Fenzl. var. billardierei” is listed by A.D.Chapman, Austral. Pl. Name Index 2919 (1991), but since the species name is illegitimate this autonym is not established, in accordance with ICN Art. 27.2 (Shenzhen Code, 2018).
• Comment: nom. illeg., nom. superfl., as the epithet spatulatum was available in Trymalium in 1837 and thus ought to have been adopted by Fenzl (ICN Art. 11.4 (Shenzhen Code, 2018)).

Bentham, G. (30 May 1863), Flora Australiensis 1: 423 [secondary reference]

nomenclatural synonym: Ceanothus spatulatus Labill. legitimate nomenclatural synonym: Pomaderris spatulata (Labill.) G.Don legitimate taxonomic synonym: Trymalium floribundum Steud. legitimate

Mueller, F.J.H. von (1882), Systematic Census of Australian Plants: 60 [replaced synonym]

replaced synonym of: Cryptandra billardierei F.Muell. nom. illeg., nom. superfl.

Diels, F.L.E. & Pritzel, E.G. (6 December 1904), Fragmenta Phytographiae Australiae occidentalis. Beitrage zur Kenntnis der Pflanzen Westaustraliens, ihrer Verbreitung und ihrer Lebensverhaltnisse. Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 35(2-3): 351-352 [secondary reference]

Ostenfeld, C.E.H. (1921), Contributions to West Australian Botany, part III : Additions and notes to the flora of extra-tropical W. Australia. Biologiske meddelelser, Kongelige Danske Videnskabernes Selskab 3(2): 85 [nomenclatural synonym]

nomenclatural synonym of: Trymalium spatulatum (Labill.) Ostenf. isonym

Rye, B.L. (31 July 1996), A synopsis of the genera Pomaderris, Siegfriedia, Spyridium and Trymalium (Rhamnaceae) in Western Australia. Nuytsia 11(1): 130 [nomenclatural synonym]

nomenclatural synonym of: Trymalium spatulatum (Labill.) G.Don legitimate

Kellermann, J., Rye, B.L. & Thiele, K.R. (2008), Nomenclatural notes, typifications and name changes in Trymalium (Rhamnaceae: Pomaderreae). Transactions of the Royal Society of South Australia 132(1): 24 [nomenclatural synonym]

nomenclatural synonym of: Trymalium spatulatum (Labill.) G.Don legitimate

Council of Heads of Australasian Herbaria (2011), Australian Plant Census: - [secondary reference]

orthographic variant: Trymalium billardieri Fenzl orth. var.

Council of Heads of Australasian Herbaria (2011), Australian Plant Census: - [nomenclatural synonym]

nomenclatural synonym of: Trymalium spatulatum (Labill.) G.Don legitimate

Kellermann, J. (7 April 2021), The importance of the ‘h’ – Parahomonymy in Trymalium (Rhamnaceae: Pomaderreae). Swainsona 35: 26 [nomenclatural synonym]

nomenclatural synonym of: Trymalium spatulatum (Labill.) G.Don legitimate

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