Utricularia brennanii is a terrestrial bladderwort native to tropical and north eastern Australia. It was recently separated from the closely related U. lasiocaulis by Jobson and Baleeiro (2022) and is named in honour of Kym Brennan from the NT herbarium.

Utricularia brennanii is a medium-sized bladderwort that is coloured pink to purple at the front and orange on the back. The lower corolla lip is variably divided into three shallow lobes, which are sometimes upturned at the edge. The palate features two raised orange ridges and is often flanked by darker purple markings. The upper corolla lip is raised upwards, narrower at the base, about half the width of the lower corolla lip and usually has an undivided margin. The spur is long, pointed and slightly constricted towards the middle. The peduncle is hairy towards the base. The traps feature wing-like projections common in the U. lasiocaulis complex.

The species has a broad distribution from Torrington in Northern NSW, sporadically appearing in the coastal heathlands of SE to central Queensland and becoming common in the tropical heathlands of Far North Queensland. It is also found in the Northern Territory. Blooming occurs as its environmental waters begin to seasonally recede. I have observed it in seepages emanating from granite outcrops, in a waterlogged grassy meadow in a broad valley, on skeletal soils atop sandstone, in creekside heathland and in the muddy floodplains of swamps.

Utricularia brennanii is most similar to its close relative U. lasiocaulis. It is distinguished by its (usually) three lobed lower corolla lip and less widely flaring upper corolla lip (The lower corolla lip of U. lasiocaulis does not have three obvious lobes and the upper corolla lip is widely flaring such that it almost meets the margins of the lower corolla lip). It is somewhat similar to the bladdeworts of the U. leptorhyncha complex by it s distinguished by its purple/orange colouration with orange palate ridges (those of U. leptorhyncha tend white with white ridges).