From Muppet Wiki

Merdlidops are sinkhole-dwelling creatures from the planet Koozebane. Hot-pink and furry with hollow socket eyes atop a cone-shaped head, they assumingly assimilate other creatures, or at least humans, into their species as evidenced on the Dom DeLuise episode of The Muppet Show.

A Merdlidop named Phyllis, who had a balloon-like nose, appeared in the "At the Dance" segment from episode 220.

Their likeness was assimilated into plastic when Palisades Toys included them on a character stand for the Reporter Kermit Action Figure.