What is the largest gray wolf subspecies?

The Yukon Wolf (also known as the Alaskan Black Wolf, Alaskan Wolf and Interior Alaskan Wolf; Canis lupus pambasileus) is considered to be the largest gray wolf species in the world, weighing around 150 to 170 lbs (68 to 77 kg) at maturity. However, the Alaskan Tundra Wolf (Canis lupus tundrarum) is thought to be the the heavier version of the Yukon Wolf, with their weight around 180 lbs (80 kg).