Dog-day cicadas are large insects with highly characteristic shapes and bodies that are twice as long as they are wide. They are 27 to 33 mm long, with wingspans of up to 82 mm. Their bodies are mostly dark with green and black markings on the upper side of the thorax. The veins at the base of the long transparent wings are also green. Significant colour variations may be related to the geographic origin of different populations. The green form described above is the most abundant.