on the bottom of his jaw. 
i've had a good look and in a human i guess it would be classed as a hairy mole.
it has 3 whisker type hairs coming out of it which feel very coarse.
i'm pretty certain it wasnt there before, though it may have just been hiding under his masses of fur before, and his recent grooming may have made it noticable.
is it a vet call or not?