The nymph taps xylem, a fluid so dilute that it must process large volumes for a small nutritional return. The excess passes out of the anus mixed with secretions from abdominal glands that stabilise it, and air pumped through a channel formed by the abdomen turns it into persistent foam. The nymph is enclosed head-downwards so the froth flows over it.
The foam gives cover from parasitoids and birds, buffers temperature and prevents desiccation in a soft-bodied insect that cannot leave its feeding site. It is not toxic and does not come from the plant.
The adult, by contrast, leaves the froth entirely and jumps. Measurements published by Malcolm Burrows in 2003 recorded froghoppers accelerating at several hundred times gravity and clearing heights of the order of seventy centimetres, giving the group a strong claim to be the best jumpers among insects for their size.