What structural feature is notably lacking in the Wheaten Terrier's single coat compared to rough-coated cousins?

Answer

Harsh undercoat

A key physical distinction of the Soft-Coated Wheaten Terrier's coat is that it is single-layered, meaning it inherently lacks the harsh undercoat found in many of its rough-coated terrier relatives. While the outer coat texture is soft, silky, wavy, or curly, the absence of the dense, harsh undercoat dictates its unique maintenance requirements compared to breeds that possess that double coat structure for protection and insulation.

What structural feature is notably lacking in the Wheaten Terrier's single coat compared to rough-coated cousins?
animalclassificationTerrierCanine