Hopper, S.D. & Brown, A.P. (29 April 2004), Robert Brown's Caladenia revisited, including a revision of its sister genera Cyanicula, Ericksonella and Pheladenia (Caladeniinae: Orchidaceae). Australian Systematic Botany 17(2): 229-230, Fig. 13 (map) [tax. nov.]

• Type: 1.1 km S of Jerramungup pub, 33 58' S 118 56' E, 1 September 1987, s.d. Hopper [sic] 5968. holo: PERTH; iso: AD, CBG, K, MEL, NSW, PERTH.

taxonomic synonym: Cyanicula caerulea subsp. apertala N.Hoffman & A.P.Br. nom. inval. taxonomic synonym: Cyanicula caerulea subsp. apertala N.Hoffman & A.P.Br. nom. inval.

Brown, A., Dundas, P., Dixon, K. & Hopper, S. (2008), Orchids of Western Australia: 138 [secondary reference]

common name: Western tiny blue orchid [n/a]

• Etymology: "open, alluding to the pronounced gap between the mid and lateral labellum lobes"

Hoffman, N. & Brown, A. (2011), Orchids of South-West Australia Edn. 3: 192 [secondary reference]

common name: Western Tiny Blue Orchid [n/a]

Clements, M.A., Howard, C.G. & Miller, J.T. (1 April 2015), Caladenia revisited: results of molecular phylogenetic analyses of Caladeniinae plastid and nuclear loci. American Journal of Botany 102(4): 597 [basionym]

basionym of: Caladenia aperta (Hopper & A.P.Br.) M.A.Clem. legitimate

Backhouse, G.N., Bates, R.J., Brown, A.P. & Copeland, L.M. (1 March 2016), Checklist of the orchids of Australia including its island territories: 20, 127 [secondary reference]

Council of Heads of Australasian Herbaria (28 February 2018), Australian Plant Census: - APC [secondary reference]

nomenclatural synonym: Caladenia aperta (Hopper & A.P.Br.) M.A.Clem. legitimate taxonomic synonym: Cyanicula caerulea subsp. apertala N.Hoffman & A.P.Br. nom. inval. taxonomic synonym: Cyanicula caerulea subsp. apertala Paczk. & A.R.Chapm. nom. inval. misapplication: Caladenia caerulea R.Br. legitimate by Hoffman, N. & Brown, A. (1984), Orchids of South-West Australia: 179 misapplication: Caladenia caerulea R.Br. legitimate by Green, J.W. (1985), Census of the Vascular Plants of Western Australia Edn. 2: 54, 193

• APC Dist.: WA

Jones, D.L. (January 2021), Native Orchids of Australia Edn. 3: 93 [nomenclatural synonym]

nomenclatural synonym of: Caladenia aperta (Hopper & A.P.Br.) M.A.Clem. legitimate

Brown, A. (19 July 2022), The Complete Orchids of Western Australia 1: 236 [secondary reference]

common name: Western Tiny Blue Orchid [n/a]

• Etymology: "From the Latin apertus (open), in reference to the pronounced gap between the mid and lateral labellum lobes."

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