The wasps can be recognised by:
- Adult wasps are between 10 to 40mm long with a cylindrical body. Adults have a spear-shaped plate (cornus) at the tail end.
- Females have a yellow abdomen with a black stripe in the middle. The female has an ovipositor on the end of its abdomen for egg-laying.- Male adults are smaller than females. The abdomen is yellow at the center with black at the base and tail end.
- Larvae are creamy white, cylindrical grubs up to 30 mm long with a dark spine at the end of the abdomen.- Larval stage usually lasts for 1-3 years before mature larvae pupate near the bark surface.