Airy Shaw, H.K. (November 1980), A partial synopsis of the Euphorbiaceae - Platylobeae of Australia (excluding Phyllanthus, Euphorbia and Calycopeplus). Kew Bulletin 35(3): 684 [comb. nov.]

basionym: Phyllanthus rigidulus Müll.Arg. legitimate

Dunlop, C.R. (1987), Checklist of the Vascular Plants of the Northern Territory. Technical Report: Conservation Commission of the Northern Territory 26: 32 [secondary reference]

Council of Heads of Australasian Herbaria (2009), Australian Plant Census: - APC [secondary reference]

nomenclatural synonym: Phyllanthus rigidulus Müll.Arg. legitimate nomenclatural synonym: Diasperus rigidulus (Müll.Arg.) Kuntze legitimate

• APC Dist.: NT, Qld

Barrett, R.L. & Telford, I.R.H. (3 November 2015), Two new species of Phyllanthus from northern Australia and notes on Phyllanthus, Sauropus and Synostemon (Phyllanthaceae) in Western Australia. Nuytsia 26: 160-163, Fig. 3 [secondary reference]

nomenclatural synonym: Phyllanthus rigidulus Müll.Arg. legitimate nomenclatural synonym: Diasperus rigidulus (Müll.Arg.) Kuntze legitimate taxonomic synonym: Sauropus sp. Cockburn Range (D.Dureau 81) WA Herbarium [n/a] common name: Shrubby Synostemon [n/a]

• Etymology: "The epithet refers to the rigid, erect habit of this species."

Parker, C.M. & Percy-Bower, J.M. (31 March 2016), Updates to Western Australia’s vascular plant census for 2015. Nuytsia 27: 15 [secondary reference]

taxonomic synonym: Sauropus sp. Cockburn Range (D.Dureau 81) WA Herbarium [n/a]

Telford, I.R.H., Pruesapan, K., Welzen, P.C. van & Bruhl, J.J. (4 June 2019), Morphological and molecular data show an enlarged tropical Australian radiation in Synostemon (Phyllanthaceae, Phyllantheae) previously concealed by heteromorphic species concepts. Australian Systematic Botany 32(2,3): 172 [nomenclatural synonym]

nomenclatural synonym of: Synostemon rigidulus (F.Muell. ex Müll.Arg.) I.Telford & Pruesapan legitimate

Parker, C.M. & Percy-Bower, J.M. (10 December 2019), Updates to Western Australia’s vascular plant census for 2019. Nuytsia 30: 347 [nomenclatural synonym]

nomenclatural synonym of: Synostemon rigidulus (F.Muell. ex Müll.Arg.) I.Telford & Pruesapan legitimate

Brown, G.K. & Bostock, P.D. (December 2020), Appendix A: New names and name and status changes 2019 to 2020. Introduction to the Census of the Queensland Flora 2020: 17 [nomenclatural synonym]

nomenclatural synonym of: Synostemon rigidulus (F.Muell. ex Müll.Arg.) I.Telford & Pruesapan legitimate

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