A cuckoo bumble bee!

On the way down from backpacking Paintbrush Divide in Grand Teton National Park this indiscriminate cuckoo bumble bee (Bombus insularis) decided to land on me for a sip of sweat! Its called the 'indiscriminate' cuckoo because it is a social parasite of several different species of social host bumble bees. This one is striking with it's fringes of yellow hairs along the sides of its abdominal tergites (fancy word for butt segments).