[3] Large insect, females 36–44 mm (excluding antennae and cerci), males generally smaller.

The prothorax is large, oval-shaped and orange and with a distinct black marking in the centre of the pronotum.

The cylindrical abdomen is slightly flattened dorsally and pale yellowish-grey with black markings.

[2] Thaumatoperla alpina are endemic to the Bogong High Plains of the Victorian alpine area in south-eastern Australia.

[3] Where introduced rainbow trout (Oncorhynchus mykiss) are absent, T. alpina nymphs are the top-level stream predators.