Thorn Treehopper

Umbonia crassicornis is a treehopper in Membracidae, within Hemiptera. Amyot and Serville named the species in 1843. [1]

Adults are typically green or yellow with reddish lines and brown markings. The pronotum rises into a conspicuous horn; its shape is especially variable in males. Young nymphs carry three horns. [1]

Records extend through South and Central America, Mexico and southern Florida. Adults and nymphs cluster on twigs and branches of woody plants. [1]

Females insert eggs into tender twig bark and tend the developing brood. The Florida account reports hatching after approximately 20 days and broods of 15–50 nymphs. [1]

Documented hosts include wild tamarind, tamarind, Jerusalem thorn and several ornamental legumes. Adults and nymphs pierce plant tissue to obtain sap. [1]

During predator encounters, clustered nymphs produce collective vibrations that advertise the attacker’s location to their defending mother. Communication travels through the host plant. [2]

Maternal signals also regulate the end of an alarm. In a 2012 experiment, communication after the predator’s eviction reduced false alarms from the offspring. The authors proposed that these signals raise the threshold at which nymphs resume collective signalling. [2]