Utricularia dunlopii is a terrestrial bladderwort from tropical Northern Territory and Western Australia. The species is notable for its extremely long filamentous appendages extending from the flower. These antennae extend from the upper corolla lip and form a ‘V’ shape, although they do not cross over each other. Three shorter appendages extend from the lower corolla lip. The spur forms a bulbous structure on the underside of the bloom. The flowers (including the stalk) are roughly 10 cm tall, and are coloured a tawny orange. Two or three blooms are usually produced on each peduncle.
U. dunlopii has a patchy distribution in the Top End of the Northern Territory and Mitchell Plateau in Western Australia. The species occupies sand plains, as well as skeletal soils atop sandstone. I observed the species on the outskirts of Darwin, where a single flower was present growing in a flat field of wet sand beneath some grasses. At the time in May, the water table had receeded to just below the surface of the ground.
The species can be distinguished from other filamentous Utricularia by examining the number of appendages on the lower corolla lip (1 in U. antennifera, 5 in U. capilliflora, 1 in U. dunstaniae and 3 in this species). It can potentially be confused with larger specimens of U. capilliflora, which is often sympatric and shares a ‘V’ shaped arrangement of the upper antennae. Close examination shows that the antennae cross over each other in U. capilliflora, but not in U. dunlopii.