Pontederia ovalis Mart. ex Schult. & Schult.f., Syst. Veg. (ed. 15 bis) 7(2): 1140. 1830.

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

5.2. Pontederia ovalis Mart. ex Schult. & Schult.f., Syst. Veg. (ed. 15 bis) 7(2): 1140. 1830.

Pontederia lanceolata f. ovalis (Mart. ex Schult. & Schult.f.) A.Cast., Arch. Jard. Bot. Rio de Janeiro 15: 62. 1957.

Pontederia cordata var. ovalis (Mart. ex Schult. & Schult.f.) Solms, Monogr. Phan. 4: 533. 1883. Lectotype (designated here). BRAZIL. s.loc., fl., s.dat., C.F.P. Martius 14 (M barcode M0242238!).

Distribution.

Costa Rica, Guatemala, Honduras, Bolivia, Brazil (states of Bahia, Maranhão, Paraíba, Distrito Federal, Goiás, Mato Grosso, Espírito Santo, Minas Gerais, Rio de Janeiro, São Paulo, Paraná, Santa Catarina and Rio Grande do Sul), Colombia, Paraguay and Uruguay.

Nomenclatural notes.

When describing P. ovalis , Schultes and Schultes (1830) mention that their new species is based in Martius specimens from Brazil. However, the author makes no mention in which herbarium the specimens are housed or their collectors’ numbers. While consulting the specimens at M, we came across two Martius’ specimens (i.e. Martius 14 M0242238; Martius 16 M0242244) that matched the protologue of P. ovalis . Both specimens were annotated in Martius handwriting and were probably analysed by Schultes. Since the specimen Martius 14 (M0242238) is a more complete collection, when compared with Martius 16 (M0242244), which is composed of two detached leaves and two inflorescences, it is selected by us as the lectotype for P. ovalis .

Taxonomical notes.

Pontederia ovalis has been considered by most authors and online databases as either a variety ( Dubs 1998, Tropicos.org 2018) or a synonym ( Schulz 1942, Tropicos.org 2018) of P. cordata . Nonetheless, both morphologically and phylogenetically, P. ovalis is much more similar to P. sagittata , due to its pubescent inflorescence main axis and fruits with sinuate ridges. Thus, P. ovalis is here re-established, being also part of the P. cordata species complex.