Synonyms: Calolisianthus acutangulus; Chelonanthus acutangulus (homotypic); Chelonanthus chelonoides; Chelonanthus leucanthus; Chelonanthus whitei; Helia acutangula; Helia alata; Helia campanulacea; Helia chelonodes; Helia chelonoides; Helia crassicaulis; Helia cujabana; Helia oerstedii; Helia oerstedtii; Helia tetragona; Helia trifidus; Helia virgata; Irlbachia alata (homotypic); Irlbachia alata alata; Lisianthius acutangulus (homotypic); Lisianthius alatus (homotypic); Lisianthius campanulaceus; Lisianthius chelonoides; Lisianthius crassicaulis; Lisianthius oerstedii; Lisianthius tetragonoalatus; Lisianthius tetragonus; Lisianthius trifidus; Lisianthus acutangulus (heterotypic); Lisianthus alatus; Lisianthus campanulaceus; Lisianthus chelonoides; Lisianthus crassicaulis; Lisianthus oerstedii; Lisianthus tetragono-alatus; Lisianthus tetragonus; Lisianthus trifidus; Lisianthus virgatus (heterotypic); Lisyanthus alatus; Penstemon chelonoides; Tetragonanthus whitei