The composition of the group has changed since the term was introduced but is now considered to consist of seven major families—Fringillidae, Emberizidae, Cardinalidae, Thraupidae, Passerellidae, Parulidae and Icteridae—plus some small families.
When Fringillidae is omitted the remaining six families are referred to as the "New World" nine-primaried oscines.
[1] In 1874 the British naturalist Alfred Russel Wallace classified the passerines by the number of primary feathers and placed ten families in his nine-primaried group, the Tanagroid Passeres:[2] Six of Wallace's families are now included in the nine-primaried oscines: Mniotiltidae, Coerebidae, Drepanidae, Tanagridae, Fringillidae and Icteridae.
They have also colonised the Galápagos (Darwin's finches) and the Tristan da Cunha group in the South Atlantic (Nesospiza and Rowettia in Thraupidae).
It is divided into 16 families:[5][6] Fringillidae Rhodinocichlidae Calcariidae Emberizidae Cardinalidae Mitrospingidae Thraupidae Passerellidae Icteridae Parulidae Calyptophilidae Phaenicophilidae Zeledoniidae