[2] A later node-based definition for Trechnotheria was the clade comprising the last common ancestor of Zhangheotherium and living therian mammals, and all its descendants.

Hence, one of the most prominent features of this group is the "hypertrophied postvallum/prevallid shearing mechanism", along with other dental characters.

Features of the shoulder blade, tibia, humerus, and ankle joint also diagnose this clade.

[5] †Gobiconodonta †Amphilestidae †Amphidontidae †Eutriconodonta †Spalacotheriida †Dryolestida †Vincelestidae †Amphitheriida †Peramuridae †Aegialodontia †Pappotheriidae Metatheria→Marsupialia Eutheria→Placentalia Alternatively, the zanjeotherids would be ancestral to both the spalacotherids and the cladotherians (driolestoids and prototribosphenids), with the tinodontids equally paraphyletic.

[4] Fruitafossor † Eutriconodonta* † Trishulotherium † Tinodon † Yermackia † Gobiotheriodon † Kiyatherium † Origolestes † Anebodon † Zhangheoterium † Maotherium † Spalacotheriidae † Meridiolestida † Chunnelodon † Dryolestida † Donodontidae † Prototribosphenida