It seems that the world's largest flea, Hystrichopsylla schefferi, lives on the mountain beaver. Until recently the species had not been photographed alive. The author of the piece below recounts her and her husband's quest to photograph the flea. The story contains pictures of the flea and the mountain beaver that they found it on. http://nyti.ms/1tjyZb1
that's the kind of story I like! I like mountain beavers and I knew they had the world's largest flea but I had no idea they were that big!! I'm glad they had a cat flea in the photo with it for scale!