Victoria (plant)

Description

Vegetative characteristics

Victoria species are rhizomatous, aquatic, short-lived, perennial herbs with tuberous rhizomes bearing contractile adventitious roots. The floating leaves are peltate and orbicular. The margin of the lamina is raised to form a rim 10–20 cm (4–8 in) high. The lamina possesses stomatodes (i.e. microscopic perforations) which are believed to allow rainwater to escape. The leaves emerge from a stipular sheath 16 cm (6 in) long and wide or more. The abaxial leaf surface possesses prominent, reticulate venation. In Victoria amazonica the leaves are glabrous, with long, hard spines and the underside is red. In Victoria cruziana the leaves are fuzzy with soft spines and the underside is purple. The shape of the rims is also different.

Generative characteristics

The up to 25 cm wide, nocturnal, thermogenic, solitary, actinomorphic, chasmogamous, protogynous flowers have prickly pedicels with 4 primary and 8 secondary air canals. The flowers have four prickly, petaloid, 12 cm long, and 7–8 cm wide sepals. The 50-100 petals gradually transition towards the shape of the stamens, however there is an abrupt change between the innermost petals to the outermost staminodia. The androeceum consists of 150–200 stamens. The gynoecium consists of 30–44 fused carpels. The 0–15 cm wide, spiny, irregularly dehiscencent fruit bears arillate, glabrous, smooth or granular seeds. Proliferating pseudanthia are absent.