Think you are right as usual Oron, we get many different kinds of leaf beetles, some very pretty! and often on the Willows. Interestingly they don't seem to be dealing with our current unseasonal cold, wet weather at the moment. My morning inspection revealed many of them seem to be dead or dying (thank goodness)- mainly the bigger ones whilst the younger ones seem to be coping better. Many thanks.
David, just for interest, the "fat" end is the head with three pairs of legs and a different "spot "pattern to the rest of the body.
Although I don't like all these pests it is ,nevertheless, interesting to observe them and know what they are such is the diversity in this area.