• Trigonium Cleve, 1867
• Trigonium adspersum Mann
• Trigonium alternans (J.W. Bailey) A. Mann, 1907
• Trigonium arcticum (Brightwell) Cleve, 1868
• Trigonium bicoronatum (Castracane) A. Mann
• Trigonium caelatum (Janisch) A. Mann
• Trigonium cinnamomeum (Grev.) Mann
• Trigonium condecorum (Ehrenberg) Hendey
• Trigonium contumax A. Mann
• Trigonium coscinoides (Grove & Sturt) Mann
• Trigonium diaphanum A. Mann
• Trigonium dissimile (Grunow) A. Mann
• Trigonium dobreeanum (Greville) Hustedt in Schmidt, 1959
• Trigonium dulce (Greville) A. Mann
• Trigonium eulensteinii (Grunow) A. Mann
• Trigonium formosum (Brightwell) Cleve, 1867
• Trigonium frauenfeldii (Grunow) A. Mann
• Trigonium geminum (A. Schmidt) A. Mann
• Trigonium glandiferum (Grunow) Hustedt, 1959
• Trigonium graeffeanum (Witt) Hendey
• Trigonium hertleinii (Hanna) V.A. Nikolaev & E. Fourtanier
• Trigonium heteroporum (Grunow) A. Mann
• Trigonium inelegans (Greville) A. Mann
• Trigonium inglorium (Crevilie) A. Mann
• Trigonium latum (Grev.) A. Mann, 1925
• Trigonium membranaceum (Cleve) A. Mann
• Trigonium moronense (Greville) T.V. Desikachary
• Trigonium multiplex (Janisch) A. Mann
• Trigonium oamaruense (Grove & Sturt) Mann
• Trigonium parallelum (Ehrenberg) Mann
• Trigonium pardus (A.F.W. Schmidt) A. Mann, 1925
• Trigonium planoconcavum (Brun) Mann
• Trigonium pseudonervatum (Grove & Sturt) Hustedt, 1959 accepted as Triceratium pseudonervatum Grove & Sturt, 1887
• Trigonium punctatum (Brightwell) A. Mann, 1925 accepted as Triceratium punctatum Brightwell, 1856 accepted as Biddulphia reticulum (Ehrenberg) Boyer, 1900
• Trigonium radfordianum (Castracane) A. Mann
• Trigonium reticulum (Ehrenberg) Simonsen, 1974 accepted as Triceratium reticulum Ehrenberg, 1844
• Trigonium rusticum D.G. Mann
• Trigonium sculptum (Shadb.) Mann accepted as Triceratium sculptum Shadbolt, 1854 accepted as Biddulphia reticulum (Ehrenberg) Boyer, 1900
• Trigonium striolatum (Ehrenberg) A. Mann, 1907 accepted as Biddulphia striolata (Ehrenberg)
• Trigonium tabellarium (Bright.) Mann
• Trigonium trinitas (Brun) Mann
• Trigonium zonulatum (Grev.) Mann
• Trigoniumaceae Glezer, 1986