Pontederia paniculata Spreng., Neue Entdeck. Pflanzenk. 3: 18. 1822.

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

1.2. Pontederia paniculata Spreng., Neue Entdeck. Pflanzenk. 3: 18. 1822.

Piaropus paniculatus (Spreng.) Small, Fl. S.E. U.S. (ed. 2): 1328. 1913.

Eichhornia paniculata (Spreng.) Solms, Monogr. Phan. 4: 530. 1883.

Cabanisia caracasana Klotzsch ex Schltdl., Abh. Naturf. Ges. Halle 6: 176. 1862, nom. superfluous. Neotype (designated here). BRAZIL. S.loc., fl., Mar 1817, M. Wied s.n. (BR barcode BR0000005188734!).

Distribution.

Pontederia paniculata possesses a peculiarly disjunctive distribution between North-eastern Brazil (states of Alagoas, Bahia, Ceará, Paraíba, Pernambuco, Rio Grande do Norte and Sergipe), north-western South America (Colombia, Ecuador, Guyana and Venezuela), Central America (Nicaragua), Antilles (Cuba and Jamaica) and North America (Mexico).

Nomenclatural notes.

When describing P. paniculata , Sprengel (1822) makes no mention of any specimen, just mentioning that his newly described species is native to Brazil. According to Stafleu and Cowan (1985), Sprengel’s herbarium was acquired by B, but later entirely lost during the WWII. The specimen Wied s.n. (BR0000005188734) is an excellent match to the diagnosis provided by Sprengel, was collected prior to the publication of P. paniculata and was originally part of the Martius Herbarium. Despite having no proof that this specimen might have been examined by Sprengel, this specimen was surely available at the time of the publication, being originally identified as P. paniculata and later examined by Seubert (1847) and identified as Eichhornia tricolor Seub, thus making it a good choice for a neotype for P. paniculata and being here designated as such.

Taxonomical notes.

The very evident disjunctions in the distribution of P. paniculata might indicate a species complex, instead of a sole species. Nonetheless, we believe that without proper studies, it would be precocious to re-establish any names or recognise any new taxa at this time.