Abstract: The biology and host plants of the distinctive longicorn beetle from eastern Australia, Thyada barbicornis (Pascoe) (Cerambycidae: Lamiinae: Zygocerini) are reviewed from the literature and from previously unpublished data. The beetle appears to be restricted to the subtropical rainforests of south-eastern Queensland and north-eastern New South Wales, where it has been recorded breeding in the wood of native fig trees, Ficus spp. [viz. Ficus macrophylla Desf. ex Pers. and F. rubiginosa Desf. ex Vent. (Moraceae)]. The food of the adults is not known for certain but adults have been recorded frequenting the foliage of fig trees. The colour pattern of the adults and the morphology and size of the antennae are described. It is suggested here for the first time that the combination of colour pattern, the form of the antennae and the habit of holding the two antennae together when disturbed, functions as crypsis and possibly mimicry for the insect. The models are most likely rainforest stink bugs (Hemiptera) or pompilid wasps (Hymenoptera).