The type description noted the taxon's similarity to the Monogolian ankylosaurids Saichania chulsanensis and Tarchia gigantea, and suggested that these three taxa form a clade within the subfamily Ankylosaurinae.
Named for its massive skull (Mongolian tarkhi meaning 'brain' and Latin ia), Tarchia currently includes only the type species, T. gigantea.
Tarchia |