''Nymphaea pedersenii'' is a species of waterlily native to Argentina, Bolivia, Brazil, and Uruguay.

Description

Vegetative characteristics

''Nymphaea pedersenii'' has ovoid to subglobose tubers. The broadly elliptic leaf blade is up to 31 cm long and 22 cm wide. The coriaceous blade of the floating leaves is connected to non-brittle, brownish, glabrescent, 7.1−10 mm wide petioles with a ring of trichomes at the apex. It has two primary central air and six secondary peripheral air canals. The leaf venation is actinodromous.

Generative characteristics

The nocturnal flowers float on the water surface. The syncarpous gynoecium consists of approximately 39 carpels with clavate, cream-coloured, curved, 1.2−1.8 cm long and 2−4 mm wide appendages. The globose apex shows rosy colouration. The ellipsoid, granulose, pilose seeds have trichomes arranged in continuous longitudinal lines.Pellegrini, M. O. O. & Jardim Botânico do Rio de Janeiro. (n.d.-b). ''Nymphaea pedersenii'' (Wiersema) C.T.Lima & Giul. Flora E Funga Do Brasil. Retrieved December 20, 2023, from https://floradobrasil.jbrj.gov.br/FB623374

Cytology

The diploid chromosome count is 2n = 18.

Reproduction

Vegetative reproduction

In Argentina, the main mode of reproduction relies on stolon formation. Proliferating pseudanthia are absent.de Lima, C. T., Machado, I. C., & Giulietti, A. M. (2021)
"Nymphaeaceae of Brasil."
Sitientibus série Ciências Biológicas, 21.

Generative reproduction

This species is not autogamous and outcrossing is obligatory. Flowering occurs throughout the year.

Taxonomy

It was first described by Wiersema in 1987 as ''Nymphaea amazonum'' subsp. ''pedersenii'', but later it was elevated to a separate species ''Nymphaea pedersenii'' by C.T.Lima and

Ana Maria Giulietti Ana Maria Giulietti Harley (born 1945) is a Brazilian biochemist, botanist, and educator known for researching ''Eriocaulaceae'', as well as her work at the University of São Paulo, State University of Feira de Santana, and Vale Institute of Tech ...

in 2021.

Type specimen

The type specimen was collected by Wiersema, Vanni and Schinini in a lagoon in Itatí,

Corrientes Corrientes (; Guaraní: Taragui, literally: "Currents") is the capital city of the province of Corrientes, Argentina, located on the eastern shore of the Paraná River, about from Buenos Aires and from Posadas, on National Route 12. It has ...

, Argentina on the 15th of April 1982.

Placement within ''Nymphaea''

It is placed in ''Nymphaea'' subg. ''Hydrocallis''.

Etymology

The specific epithet ''pedersenii'' honours Troels Myndel Pedersen.Wiersema, J. H. (1987). A monograph of ''Nymphaea'' subgenus ''Hydrocallis'' (Nymphaeaceae). Systematic Botany Monographs, 1-112.

Ecology

Habitat

In Brazil, it was observed in a stream with up to 3 m depth in the state

Pará Pará () is a Federative units of Brazil, state of Brazil, located in northern Brazil and traversed by the lower Amazon River. It borders the Brazilian states of Amapá, Maranhão, Tocantins (state), Tocantins, Mato Grosso, Amazonas (Brazilian st ...

and in permanent or temporary lagoons in the

Pantanal The Pantanal () is a natural region encompassing the world's largest tropical wetland area, and the world's largest Flooded grasslands and savannas, flooded grasslands. It is located mostly within the Brazilian state of Mato Grosso do Sul, but i ...

. In Argentina, it was observed growing in a lagoon.

Pollination

It is pollinated by the beetle species '' Cyclocephala mollis''. Beetles have been found trapped within the flowers.

References

{{Taxonbar, from=Q123930073, from2=Q21383937 pedersenii Flora of Argentina Flora of Bolivia Flora of Brazil Flora of Uruguay Flora of Southern America Plants described in 1987