Until I was filing away my recent photos of this creature, I’d forgotten that I actually saw one – my first, the one shown below – tootling along amongst the stones and sparse vegetation in King Barrow quarry on the Isle of Portland during my visit last September.

I spotted this second beast on a wall in a local street very recently. And, at around 12mm long (measured by taking a photo of my left index finger right next to it), this crustacean really was a beast, and, according to the Naturespot website, they can grow to 20mm so this one wasn’t even fully grown.

Meet the Southern pill woodlouse (Armadillidium depressum), a creature that curls itself into a ball when threatened and which can be distinguished from your common or garden Pill woodlouse (Armadillidium vulgare) by the way the sections of its armadillo-like outer skin curve up slightly at the ends.