Pyralidae in the context of Crambidae

A tympanal organ (or tympanic organ) is a hearing organ in insects, consisting of a tympanal membrane (tympanum) stretched across a frame backed by an air sac and associated sensory neurons. Sounds vibrate the membrane, and the vibrations are sensed by a chordotonal organ. Hymenoptera (bees, wasps, ants, etc.) do not have a tympanal organ, but they do have a Johnston's organ.

Tympanal organs have evolved in at least seven different orders of insects. Tympanal organs can occur in just about any part of the insect: the thorax, the base of the wing, the abdomen, the legs, etc., depending on the group of insects. The structures are thought to have evolved independently many times. As a result, their position and structures are often used to help determine the taxonomy of the species. For example, all members of the Geometridae share distinctive paired abdominal tympanal organs that open towards the front side of the first abdominal segment. Within the organ, particular structures vary in shape and are used to indicate shared ancestry of subfamilies. In other families of Lepidoptera having abdominal tympanal organs, the opening may be in a different orientation and the structures differ in shape.

Cadra calidella, the dried fruit or date moth, is a species of snout moth in the genus Cadra and commonly mistaken for the species Cadra figulilella. It thrives in warmer conditions and is found primarily in Mediterranean countries, although it can also be found in Central Asia, Kazakhstan, Transcaucasia, Caucasus, and the western part of Russia. It feeds on dried fruits, carobs, nuts and seeds, hence earning its colloquial name. This diet damages the food industry, and it is a common storage pest. Because of this, much research has been done to study ways to limit its reproduction rate and population size. It was first described by Achille Guenée in 1845.