The Pentatomidae (shield bugs), some of which are metallic or otherwise brightly coloured, are easily recognized by the great development of the scutellum, which reaches at least half-way back towards the tip of the abdomen, and in some genera covers the whole of the hind body, and also the wings when these are closed.
The Coreidae have a smaller scutellum, and the feelers are inserted high on the head, while in the Lygaeidae they are inserted lower down.
In the curious little Tingidae, whose integuments exhibit a pattern of network-like ridges, the feet are two-segmented and the scutellum is hidden by the pronotum.
The Aradidae have two segmented feet, and a large visible scutellum.
The part in contact with the endosperm is plate-like, and is known as the scutellum; the surface in contact with the endosperm forms an absorptive epithelium.