Unusual merles

Most merle dogs are the 'classic' red or blue merles, or in rarer cases, merling of another pattern like brindle or sable. But there are also unusual merles that can't quite be put in with the others. The genetics behind them are almost entirely unknown.

Dilute spots

Some merles appear to have a patch or two where the merling is lighter or darker than on the rest of the dog.

Tweed

Some dogs have a third (or even fourth!) shade in the coat, which gives a very marbled look. These dogs are sometimes referred to as tweed merles or harlequins (not to be confused with the great dane pattern).

Tweed merle catahoule leopard dog

Dilute spot on a blue merle collie