Chow Chows are well-known for their distinctive bluish-black tongues. This breed is one of the most recognizable for this trait.
Chinese Shar-Peis are another breed that often has blue-black tongues. The breed's loose, wrinkled skin and unique tongue color make them stand out.
The Eurasier is a breed developed in Germany and is known for having a black or blue tongue.
Thai Ridgebacks are a rare breed with a black or blue tongue. They are native to Thailand and have a unique appearance.