Marsupial was the term for a group of animal species, linked together in systematic biology. Altarian marsupials and kangaroos were examples of marsupials.
The planet Archer IV had several nocturnal marsupials living on it in 2151. (ENT: "Strange New World")
A type of marsupials, living on a planet in 2153, produced saliva which served as a natural anticoagulant. (ENT: "Bounty")