Molecular Systematics and Plumage Evolution in the Monotypic Obligate Army-Ant-Following GenusSkutchia(Thamnophilidae)

We obtained 1403 base pairs of mtDNA sequences of cyt b and ND2 from four specimens of the Pale-faced Bareeye (Skutchia borbae, representing a monotypic genus of the Thamnophilidae) and evaluated for the first time the species' phylogenetic position among core obligate army-ant-following antbirds. All trees placed Skutchia borbae consistently and with high statistical support as sister to the Black-spotted Bare-eye (Phlegopsis nigromaculata) in a clade with the two known species of Phlegopsis. This result supports the return of S. borbae to the genus Phlegopsis, where it was originally placed. When the plumage characters originally used to diagnose Skutchia are mapped onto the phylogeny, it is evident that they have evolved convergently multiple times in core obligate army-ant-following antbirds. This discovery further supports merging Skutchia with Phlegopsis.