Macropophora accentifer (Olivier, 1795)
Cerambycidae: Lamiinae: Acanthoderini; Also known as yellow harlequin, trunk drill, small harlequin.
In citriculture, this pest attacks only the trunks. It can be found in other crops such as avocado, blackberry, fig, peach and in forest essences.
I guess I need to watch my lemon tree more closely...