Euarchonta

The Euarchonta are a grandorder of mammals containing four orders: the Dermoptera or colugos, the Scandentia or treeshrews, the extinct Plesiadapiformes, and the Primates.

The term "Euarchonta" (meaning "true ancestors") first appeared in the general scientific literature in 1999, when molecular evidence suggested that the morphology-based Archonta should be trimmed down to exclude Chiroptera. Major DNA sequence analyses of predominantly nuclear sequences (Murphy et al., 2001) support the Euarchonta hypothesis, while a major study investigating mitochondrial sequences supports a different tree topology (Arnason et al., 2002). A study investigating retrotransposon presence/absence data has claimed strong support for Euarchonta (Kriegs et al., 2007). Some interpretations of the molecular data link Primates and Dermoptera in a clade (mirorder) known as Primatomorpha, which is the sister of Scandentia. In some the Dermoptera are a member of the primates rather than a sister. Other interpretations link the Dermoptera and Scandentia together in a group called Sundatheria as the sister group of the primates. Together, the three are known as Euarchonta, the "True Founders".

Euarchonta and Glires together form the Euarchontoglires, one of the four Eutherian clades.

Note that as eu- becomes ev- before vowels in Latin, Euarchonta is not a proper Latin phonological construct—Evarchonta would be appropriate. This is applied inconsistently in English, for example in euergetism on one hand and evangelism on the other.