Potamogeton ×jacobsii (Potamogetonaceae) from New South Wales, Australia – the first Potamogeton hybrid from the Southern Hemisphere

Although more than 80 hybrids are documented for Potamogeton in the Northern Hemisphere, the hybrid diversity in the Southern Hemisphere is largely unknown. A taxonomically uncertain Potamogeton plant discovered in New South Wales, Australia, was subjected to detailed morphological investigation and molecular analyses to discover its exact identity. Both approaches resulted in the identification of the Potamogeton specimen as P. crispus P. ochreatus, which is a previously unrecorded hybrid and is here described as Potamogeton jacobsii nothosp. nova. Although P. crispus is known to hybridise with many other species, P. jacobsii is the first known hybrid involving P. ochreatus.