From Muppet Wiki

Bugsy Them was the villain in Dog City, threatening Ace Yu because his (Ace's) father's money went to his son rather to him.

This mad bulldog was the leader of a canine mafia, and enjoyed anything senseless. He is also the owner of the longest known tail of a bulldog, though it was likely a prosthetic one well-groomed by Miss Belle, his go-to gal in crime.

In the Dog City series, the animated sections reworked the character as Bugsy Vile, while the puppet was reused as Bruno in the Muppet segments.