Pontederia triflora (Endl. ex Seub.) G.Agostini et al., Ernstia 27: 9. 1984.

Pellegrini, Marco O. O., Horn, Charles N. & Almeida, Rafael F., 2018, Total evidence phylogeny of Pontederiaceae (Commelinales) sheds light on the necessity of its recircumscription and synopsis of Pontederia L., PhytoKeys 108, pp. 25-83 : 25

5.7. Pontederia triflora (Endl. ex Seub.) G.Agostini et al., Ernstia 27: 9. 1984.

Reussia triflora Endl. ex Seub., Fl. Bras. 3(1): 96. 1847. Type (not found). BRAZIL. Pohl; Sellow (B?).

Distribution.

Colombia, Venezuela, Guyana, Bolivia, Argentina and Brazil (states of Roraima, Mato Grosso, Mato Grosso do Sul and Minas Gerais).

Nomenclatural notes.

Due to the impossibility of finding the type specimen(s?) of Reussia triflora in any of the visited herbaria, we do not designate any types for this name at this point.

Taxonomical notes.

Pontederia triflora has been greatly confused with P. subovata , since its original description as R. triflora by Seubert (1847). Both species share similar habit, leaf and floral morphology. Nonetheless, in P. triflora , the petiolate leaf-blades are linear-lanceolate to linear-elliptic or linear rhomboid (vs. emergent and elliptic to narrowly ovate to ovate or subrhomboid in P. subovata ) and the inflorescences are 2 –4(– 5)-flowered [vs. (6 –)8– 20-flowered]. Thus, we reaffirm P. triflora as an accepted name, distinct from P. subovata .