Nymphaea jacobsii is a species of waterlily endemic to Queensland, Australia.
Nymphaea jacobsii is an annual or perennial aquatic plant with elongate to globose rhizomes. The broadly elliptic, 40 cm long, 35 cm wide, petiolate leaves have a dentate margin.
The inodorous flowers extend up to 30 cm above the water surface. The sepals are 4.2âÂÂ13 cm long, and 5.5 cm wide. The 12-24 white to deep blue, lanceolate petals are 1âÂÂ11.5 cm long, and 2.5-5.5 cm wide. The androecium consists of 150-300 yellow stamens. The gynoecium consists of 12-25 carpels. The globose, 2.3âÂÂ9 cm wide fruit bears numerous large, ovoid, 2.6âÂÂ7 mm long and 2âÂÂ3.5 mm wide seeds with 0.1-0.13 mm long trichomes.
It was first described by Carl Barre Hellquist in 2011.
The Type specimen was collected by S. W. L. Jacobs and C. B. Hellquist in Lake Powlanthanga, Queensland, Australia on the 12th of June 2007.
Two subspecies, namely Nymphaea jacobsii subsp. jacobsii, and Nymphaea jacobsii subsp. toomba Hellq., have been described.
It is placed in Nymphaea subgenus Anecphya.
A natural hybrid of Nymphaea jacobsii and Nymphaea violacea has been described, but not named.
It is named after Surrey Wilfrid Laurance Jacobs.
The NCA status of Nymphaea jacobsii is Special Least Concern (SL).
It is found in lakes, and creeks.