While cutting back a dead vine I have, I found several of these grubs living in small chambers within the vine trunk. I don't know what it is and whether it was the cause of the vine's death.
No identification made yet.
No interactions present.
I guess that Vine Weevil is a possible candidate, although I'm not sure how far they normally burrow into woody stems like this, they're usually underground among the roots as far as I know. Do you have any other photos showing the grub itself more clearly?
Entomologist and biological recorder
my experience of vine weevil larvae is they live in loose compost and eat relatively soft plant roots, so I'm not convinced by this. My best guess is that it is some sort of long-horn beetle (Cerambycidae) or other stem boring beetle, but that's just a guess. In north America there are clearwing moths and stem boring beetles that attack grape stems/rootstocks and are considered serious pests, hopefully it is not one of these! If you find it again, it would be helpful to have a better picture of the larva and ideally the adult insect if you can rear it.
Lat/Lng: 51.32142, -0.17505
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