We found this yesterday, clearing grasses from a steep slope behind the Croft.
It looks like a snake, shortened. In fact (and I only know this thanks to my friend Constantí Stefanescu at the Catalan Butterfly Monitoring Scheme) it is a final stage larva of the Convolvulus Hawkmoth. At the end of the summer, says Constantí, they burrow underground in preparation for pupating.
The good news is that her or his name, Convolvulus, comes from the fact that they eat Convolvulus arvensis, Field Bindweed. As we have to wage a constant war against the horrible binding weed around the Croft, it's great to know that we have an ally. And a meaty one at that.