mon·o·phy·let·ic 
(mŏn′ō-fī-lĕtĭk)
(mŏn′ō-fī-lĕtĭk)adj.
1. Of or relating to a group of taxa that includes the common ancestor of all the members as well as all descendants of that ancestor.
2. Of or derived from one stock or source.
mon′o·phy·letic·al·ly adv.
mono·phy′ly (mŏnə-fī′lē, mə-nŏfə-lē) adv.