Tectocoris diophthalmus Thunberg, 1783 (Scutelleridae)
Tectocoris diophthalmus Thunberg, 1783 (Scutelleridae, Tectocorinae). Common Name: Hibiscus Harlequin Bug or Cotton Harlequin Bug. They are a brightly coloured convex and rounded shield-shaped bug with a metallic sheen. Adult females are mostly orange and males are both blue and red or orange. The nymphs are often very differently coloured. These nymphs are quite similar to the males. Colours are variable. It lives in Northern and Eastern Australia, New Guinea and several Pacific Islands. Its main native host plant is Beach Hibiscus (Hibiscus tiliaceus in the Malvaceae family) but will suck sap from other species. The bright colours serve as a signal for toxicity to ward off potential predator. They also emit a foul "stink" if annoyed. Females guard their eggs until all young have hatched.