The echidna 's fur may be infested with what is said to be the world 's largest flea , Bradiopsylla echidnae , which is about 4 mm ( 0.16 in ) long .
The Echidna 's fur may be infested with what is said to be the world 's largest flea , Bradiopsylla echidnae , which is about 4 mm long .