Maze-back Bug

Size 3mm. Fast moving on our lemon tree. Its back has a unique pattern. It looks like a brown/white maze of thin lines, ending in a wide conical band on the dorsal apex. I assumed it was a ladybird, but found better matches in leaf beetles. The long antennae certainly don't match ladybirds well. Any help for identification is appreciated. Update 29/11/2016: This species is staying around. I found several matches in the Thyanta genus, especially Thyanta pallidovirens, but none of them is really reliable. I still think that it may be a Stink or Shield Bug. It is certainly a nymph and could even be the juvenile of the Green Shield Bug (Nezara viridula listed elsewhere, also in need of being reviewed).