Amazon Basin of South America
Waterhyacinth (Pontederia crassipes)
Eggs are elliptical and milky white when laid but turn yellowish with reddish eye spots before hatching. Nymphs are similar to wingless adults but are smaller (up to 2½ mm long). Nymphs have yellowish bodies with mottled brown markings; their coloration darkens through each instar. Adults can be either wingless or winged (with clear wings). Adults are typically 2½–3½ mm long and are mottled brown, gray, and yellowish.
At warm locations with winter temperatures above freezing, both M. scutellaris and waterhyacinth develop throughout the year. At cold sites, immature stages overwinter in decaying mats of waterhyacinth. Adults lay eggs within leaves of waterhyacinth in spring; oviposition scars can be recognized by three parallel marks. Nymphs develop through five instars. Nymphs and adults feed on leaves and stems of waterhyacinth. Environmental cues determine whether adults will be winged or wingless. When planthoppers are overcrowded or waterhyacinth plants are of poor quality, adults develop wings (i.e., become macropterous) that enable them to disperse to more suitable waterhyacinth plants/infestations. There are multiple overlapping generations per year.
Nymphs and adults pierce waterhyacinth leaves and stems and feed on sap. Plants with heavy feeding produce fewer leaves and eventually wilt and die.
Smith, M.C., A.B.C. Goode, and N.E. Harms. 2022. Waterhyacinth Biocontrol Agents: History and Ecology in North America. In: R.L. Winston, Ed. Biological Control of Weeds in North America. North American Invasive Species Management Association, Milwaukee, WI. NAISMA-BCW-2022-16-WATERHYACINTH-A. https://bugwoodcloud.org/resource/files/25358.pdf