Lygidolon flavoscutellatus (Lindberg, 1958)
Lygidolon lindbergi (Ghauri, 1971)
Necrotic tissue develops around punctures in the pinnules because of the apparently phytotoxic saliva injected into the plant tissue whilst feeding. The bark turns into a dull, greyish colour with dark blotches and the leaves begin to shed. Plantations become “skeletonised”. Infestation by wattle mirid can cause distorted and stunted tree growth. Following heavy infestation, multiple leaders develop on the damaged shoots resulting in the “witches’ broom” effect. It is also possible to see active small mirids on the leaves and branches.
Nymphs are green with no wing pads and therefore cannot fly. They are however active and can move between trees when the trees touch.
Adults: The mirid is approximately 3 mm, it is black or chestnut brown, with a yellow triangular scutellum (yellow spot on the back). This mirid can be confused with the wattle leafhopper (Iassomorphus cedaranus).
The female lays eggs approximately 9 days after mating. The female lives for 40 days and lays its eggs on young shoots and developing tissue. The eggs hatch after 6 to 14 days. The larval stage consists of five nymphal stages and lasts between 14 to 20 days. The entire life cycle lasts 4 to 5 weeks.
The “witches’ broom” and forking can be pruned out but this is labour intensive. The pruning should be done during the winter months. Sticky traps are used to monitor the mirids presence. Extensive surveys of the mirid and its damage should be conducted during the first two years after the tree has been planted. Chemical control is considered when mirid populations are high. Aerial and ground application (mist blowers) are commonly used.
Ingham DS, Samways MJ, Govnder P. 1998. Monitoring the brown wattle mirid, Lygidolon laevigatum Reuter (Hemiptera: Miridae). African Entomology 6: 111-116.
Little K. 2021. Fungicides and an insecticide tested for the control of wattle rust and brown wattle mirid in Acacia mearnsii plantations. Southern Forests: a Journal of Forest Science 83: 144.157.
Wheeler AJ. Biology of the plant bugs (Hemiptera: Miridae): Pests, predators, opportunists. Comstock publishing Associates, Cornell University Press, Ithaca and London.
Lygidolon laevigatum Reuter, 1907 in GBIF Secretariat (2021). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2022-08-17.
