. The other major clades are colored: marsupials (magenta), xenarthrans (orange), afrotherians (red), and laurasiatherians (green).
External classification The Euarchontoglires clade is based on
DNA sequence analyses and
retrotransposon markers that combine the clades
Glires (Rodentia + Lagomorpha) and
Euarchonta (Scandentia + Primates + Dermoptera). It is usually discussed without a
taxonomic rank but has been called a cohort, magnorder, or superorder. Relations among the four cohorts (Euarchontoglires,
Xenarthra,
Laurasiatheria,
Afrotheria) and the identity of the placental root remain controversial. So far, few, if any, distinctive anatomical features have been recognized that support Euarchontoglires; nor does any strong evidence from
anatomy support alternative hypotheses. Although both Euarchontoglires and
diprotodont marsupials are documented to possess a
vermiform appendix, this feature evolved as a result of
convergent evolution. Euarchontoglires probably split from the
Boreoeutheria magnorder about 85 to 95 million years ago, during the
Cretaceous, and developed in the
Laurasian island group that would later become
Europe. This hypothesis is supported by molecular evidence; so far, the earliest known
fossils date to the early
Paleocene. The combined clade of Euarchontoglires and Laurasiatheria is recognized as
Boreoeutheria.
Internal Classification The hypothesized relationship among the Euarchontoglires is as follows: }} One study based on DNA analysis suggests that Scandentia and Primates are sister clades, but does not discuss the position of Dermoptera. Although it is known that Scandentia is one of the most basal Euarchontoglires clades, the exact phylogenetic position is not yet considered resolved, and it may be a sister of Glires, Primatomorpha or Dermoptera or to all other Euarchontoglires. Some old studies place Scandentia as sister of the Glires, invalidating Euarchonta. ==References==