Grote's Tussock Moth (Calliteara grotei, 线丽毒蛾).
They range from the Himalayas to southeast Asia. It has been an unseasonably warm November in Changsha, so everywhere one examines nature, life seems to be experiencing one last hurrah before cold weather is unbridled: each week there are new flowers, new birds and new insect larva to be found. Recently these yellow and white caterpillars have been present on Yuelu Mountain in conspicuous numbers; it is the first time I have noticed any of them so far this year. Often they have been feeding and shedding their hair on broad-leaf trees. Two, we found resting together on a warm rock near the mountain summit. When disturbed, they raise their bristles and stare at you with their jet black eyes, but we left them unmolested as possible, so they could enjoy and destroy their allotments of woodland shrubbery.
