Drosera lasiantha is a pygmy sundew endemic to the Porongurup Range and nearby national park in southern Western Australia. It notably forms a towering stem of old growth, which can reach several centimetres high in the oldest specimens. Atop this stem is a raised rosette of leaves. The plant is very restricted in range, growing only on the laterite scree slopes of a few mountains.
Drosera lasiantha is has a small rosette of raised leaves. This rosette is borne on top of a long stem of old growth. The flower stalk and sepals are covered with long woolly hairs (with no glands) as well as short hairs with glands at the end. The flowers are pink.
The species grows in the Porongurup Range and Mount Lindesay National Parks where it inhabits laterite scree slopes and skeletal soils atop granite.
The towering morphology is shared by Drosera gibsonii, D. scorpioides and D. dichrosepala. Whilst their niches do not really overlap, Drosera lasiantha can be distinguished by its floral scape, which is covered with a thick layer of woolly, non-glandular hairs as well as short glandular indumenta (The scapes of D. gibsonii have dense glands but no long hairs, D. scorpioides has long hairs with glands and D. dichrosepala is almost glabrous).