Drosera falconeri is a species within the section Lasiocephala (Petiolaris complex) endemic to the Darwin area of the Top End. The species is famous for its iconic expanded laminae, which are bright red and often noted for their similarity to the traps of the venus fly trap.
D. falconeri is a medium sized sundew that grows around 5 cm in diameter. The lamina is extremely expanded and reniform in shape. The petiole is broad. The leaves lie flat on the ground. The plants are usually blood red in colour, tending towards bronze when shaded. As the wet season ends, the plants tend to form smaller leaves or stops producing leaves altogether as it begins storing energy for dormancy. Unlike most other species in the Petiolaris complex, D. falconeri does not form an insulating resting bud. Instead it retreats underground as a resting corm beneath the dried clay substrate. The species is amongst the first in the subgenus to enter dormancy, immediately initiating the process when the rains stop. Flowering occurs at the onset of the wet season.
D. falconeri grows in the clayey floodplains depositied by large rivers south west of Darwin and on Bathurst Island. The habitats are frequently inundated during heavy rain, and the species can grow underwater during exceptionally wet periods. More commonly, the water drains off rather quickly. In the later half of the wet season, this habitat is covered by dense spear grass that grows up to 2m tall. The species grows in a grey sandy silt substrate, which is pliable when wet but dries rock hard. Although it is a common belief that the substrates are alkaline, my own sampling of the top soil show an acidity of around pH 5.
Drosera falconeri is unlikely to be confused with other sundews. It appears most closely related to D. kenneallyi sharing reniform laminae (much smaller in D. kenneallyi) and growing habit (flat rosette with a lack of hairy dormant bud). The species is easily distinguished by its large laminae. In nature, it often hybridises with D. brevicornis and D. darwinensis, especially near roadside embankments where the taxa are brought into close proximity.
