Illyria viridis, the yidiyidi, is a species of singing cicada found in Western Australia.

Adults inhabit tall grass, which grows near little water channels, typically in a mixture of both live and dead leaves.

The insect has a brown rostrum that becomes black at the tip as it reaches the bases of the hind coxae.

Scutal depressions; black submedian and lateral sigilla on the mesonotum, with the latter occasionally reticulate.

A large black suffusion covers the anterior distal half of the opercula, which are wide and rounded.