Lychee Stink Bug

Common name for a species of giant Stink Bug, with the scientific designation Tessaratoma papillosa, which is also commonly known as Lychee Giant Shield Bug. Nymphs are vividly coloured and undergo several successive stages of moulting, known as ecdysis, in which they increase in size and become more adult-like with each stage of moulting, which is individually known as an instar. In the first nymphal instar, just after hatching from their eggs, the nymphs are greyish with a white V-shaped line, as well as a central white stripe on the back; white legs with black tarsi, i.e. the final segments of the legs; white antennae with black tips; and reddish spots on the outer side of each of the tiny black eyes (fig.). In an older nymphal instar, the centre of the shield as well as the feet of the nymphs become orangey, while the white V-shaped pattern, as well as a central white stripe on the back, remains unchanged (fig.). After the final moulting, the adult Lychee Stink Bug is dull brown in colour and now has wings. Lychee Stink Bugs feed exclusively upon plants and spent most of their lives in tree leaves. They are considered an agricultural pest in lychee, longan and rambutan crops. When threatened they use chemical defenses, known as allomones, which they produce in glands in their thorax, and is notable for being one of the most incapacitating to vertebrates. It can squirt a strong jet of this chemical up to a distance of about 30 centimeters, which –while lethal to fellow anthropods– can cause damage upon contact to the human skin, and even cause temporary blindness if sprayed in the eyes. In Thailand, where Lychee Stink Bugs are called muan lamyai (มวนลำไย), this species of bug is eaten as food. 回