Palaeos:		Cladistics
Phylogeny and systematics		Paraphyly

Definition: Paraphyly

The Paraphyletic taxon is a group of organisms in which the most recent common ancestor of all those organisms and some, but not all, of that ancestor's descendents are included.  Paraphyletic taxa are recognized in Linnaean and evolutionary systematics but not in cladistics.

Illustration: the Class Reptilia gave rise to mammals and birds, but neither mammals nor birds are included under Reptilia.

Examples:  Invertebrates, Amphibia, Reptilia, Dinosauria if excluding birds, Gymnosperma, etc.