Neither do Leghorns, but this is a mix, and we're only taking stabs in the dark trying to guess with mixed breeds. His tail looks pretty long and full to me for a mix, it's just carried higher than a purebred Yokohama or splash Sumatra would. He could easily be an Andalusian mix, too.If he has significant Yokohama influence I would expect to see a longer tail and no black flecks. Yokohama chickens do not come in any variety that would lead to black flecks.