I found this larva on a Bindweed leaf on August 28th,the Bindweed was growing through Gorse which had GreenHairstreak butterflies perching in it earlier in the season.I am not sure if damage to leaf is due to catterpillar or the gorse spines,although it remained on the leaf for 3-4 days,it was 22-25mm long.Can anyone help with an id please?
I am pretty sure that this funky little caterpillar is that of the Plume moth, Emmelina monodactyla - I say 'pretty sure' as several species have pretty similar looking caterpillars but I think this is the principal Convolvulus feeding species.
It is a common and widespread species, the caterpillars making lace-work out of the leaves with their feeding.
Thanks Bombuscolorum for that id,I am not sure its Emmilina monodactyla as I have seen this species .There was no colour other than the green you see in photo,and the shape was getting narrower towards the tail ,it was also more segmented than the Emmilina monodactyla that I have seen.
Of course it could be a different stage of development of the larva also. The other plume moth species are also a possibility as you suggest too.