Hallegraeff, G. et al. (2020), The marine planktonic dinoflagellate Tripos: 60 years of species-level distributions in Australian waters. Australian Systematic Botany 33: 3396, Table 2 [comb. nov.]

basionym: Ceratium symmetricum Pavill. legitimate

Guiry, M.D. & Guiry, G M. (2021), -. Algaebase web site: www.algaebase.org: - AAL [secondary reference]

nomenclatural synonym: Ceratium tripos var. gracile Gourret nom. illeg. nomenclatural synonym: Ceratium symmetricum Pavill. legitimate nomenclatural synonym: Neoceratium symmetricum (Pavill.) F.Gómez, D.Moreira & López-García legitimate taxonomic synonym: Ceratium gracile (Gourret) Jørg. nom. illeg.

Gómez, F. (2021), Speciation and infrageneric classification in the planktonic dinoflagellate Tripos (Gonyaulacales, Dinophyceae). Current Chinese Science 1(3): 370 [secondary reference]

ABRS (2023), Australian Algal Name Index Edn. 2023 (Australian algal updates): - [secondary reference]

taxonomic synonym: Tripos symmetricus nom. inval.

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