South America
Alligatorweed (Alternanthera philoxeroides)
Eggs are elongated and yellow at first but turn reddish with age. Nymphs are up to 2 mm long. The first nymphal stage is pale yellow, but nymphs turn increasingly orange to red with black legs through subsequent stages. Adults can be either wing-less or winged (with fringed wings). Most winged forms have only short wings and are flightless; long-winged forms are uncommon. Adults are 2 mm long and black with black legs and antennae.
Eggs are laid singly (an average of 200 per female) on hairs at alligatorweed stem nodes. Unmated females produce all males, but females that are fertilized produce equal amounts of male and female progeny. Adults and nymphs feed on new growth of alligatorweed leaves and stems. There are multiple overlapping generations per year; 4–5 generations have been observed in the native range. All stages can overwinter, though the most common overwintering stage is adult.
Nymphs and adults puncture alligatorweed leaves and stems and suck out cell contents. Feeding causes leaf and tip deformation which stunts plants. This typically does not kill plants so the overall impact is not severe.
Harms, N.E., I.A. Knight, and P.D. Pratt. 2022. Alligatorweed 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-2022-25-ALLIGATORWEED-A. https://bugwoodcloud.org/resource/files/23221.pdf