Autapomorphy vs. Apomorphy

Autapomorphynoun

(cladistics) A derived trait that is unique to a particular taxon

Autapomorphynoun

An autapomorphic character.

Autapomorphy

In phylogenetics, an autapomorphy is a distinctive feature, known as a derived trait, that is unique to a given taxon. That is, it is found only in one taxon, but not found in any others or outgroup taxa, not even those most closely related to the focal taxon (which may be a species, family or in general any clade).

Apomorphynoun

(systematics) A derived characteristic of a clade. Any feature novel to a species and its descendants.

Apomorphynoun

An apomorphous character.