Insect foam on a plant stalk. Close up of foam encasing an insect nymph (immature form). This insect is most likely to be a froghopper (superfamily Cercopoidea), as these are characterised by their production of frothed plant sap, which resembles spittle. The nymphs of these insects, which produce the foam during their development into adults, are therefore known as spittlebugs or spit bugs. The foam, sometimes called cuckoo spit, is important for hiding the nymph from predators and parasites and for keeping them moist. It also insulates against heat and cold, providing thermal control. Photographed in Zamora-Chinchipe, Ecuador.