We found this in our garden and can not seem to identify it at all, looked through numerous images on moth and butterfly caterpillars and nothing seemed to match it. Please would really appreciate an identification, as my 3 year old boy wants to watch it pupate and I want to make sure we look after it.
This is the larva of the Dot Moth (Melanchra persicariae), they want to overwinter as a pupa, in an underground cocoon. They feed by day and night, on a wide range of wild and cultivated herbaceous and woody plants, Common Nettle, Hop, Field Bindweed, Dock, Groundsel, Michaelmas-daisy, black currant, ivy, hazel...loads of trees etc. so surely you can find something suitable for him to eat until he is ready to pupate, which should be between now and October.
Just place a inch or so of dirt into a good sized container, with a bit of leaf liter on top, cut food plant and place into wet sponge in a small jar and let him go. If you keep it inside all winter be sure to moisen the dirt once a week or so, and keep it in a cool/cold location. They should emerge around June.