Thosea sinensis (扁刺蛾).
A species of slug caterpillar moth. Several times in early July, I came across these caterpillar on rocks and maesa trees in the forested areas on and around Yuelu Mountain (嶽麓山). So often were they in the company of tiny ants that I suspected they might be myrmecophiles. I have not seen any since, until today when I came across one late summer straggler.
