Nuphar ulvacea

Nuphar ulvacea is a species of rhizomatous aquatic plant native to the US-American states Alabama and Florida.

Vegetative characteristics
Nuphar ulvacea is an aquatic plant with stout, 2-5 cm wide rhizomes with 11-13 mm long, and 8-9 mm wide leaf scars. The petiolate, lanceolate, glabrous floating leaves with a blunt apex are 115-165 mm long, and 54-66 mm wide. The glabrous, terete, smooth petiole is 45-70 cm long, and 7 mm wide. The very thin submerged leaves are 23-28 cm long, and 7-10 wide.

Generative characteristics
The flowers, supported by long peduncles, extend above the water surface. They are 15-18 mm long, and 20-23 mm wide. They have six sepals. The subglobose, prominently ribbed fruit bears 3.5-4 mm long, and 2.5 mm wide seeds.

Generative reproduction
Flowering occurs from Spring to early Autumn.

Publication
It was first described as Nymphaea ulvacea G.S.Mill. & Standl. by Gerrit Smith Miller Jr. and Paul Carpenter Standley in 1912. Later, it was included in the genus Nuphar Sm. as Nuphar ulvacea (G.S.Mill. & Standl.) Standl. published by Paul Carpenter Standley in 1931.

Type specimen
The type specimen was collected by A. H. Curtiss in a blackwater River near Milton, Florida, USA on the 14th of May 1898.

Etymology
The specific epithet ulvacea references the genus of algae Ulva, as the submerged leaves of Nuphar ulvacea resemble it.

Conservation
Its habitat is imperiled.

Habitat
It occurs in blackwater habitats, streams fed by springs, and old, water-filled sand and gravel pits.