WARBLER  

The name warbler is used for birds of two subfamilies of the flycatcher family, Muscicapidae; for birds of the New World wood warbler family, Parulidae; and for several species of birds in the thrush family, Turdidae.

The Old World warblers are more than 300 species of birds constituting the subfamily Sylviinae of the flycatchers. They are generally grayish, greenish, or brownish, but some African species are highly colorful. Only three members of this subfamily occur regularly in the New World: the ruby-crowned kinglet, Regulus calendula; the golden-crowned kinglet, R. satrapa; and the Arctic warbler, Phylloscopus borealis. Among the most ancient of songbirds, the subfamily Sylviinae is regarded by many authorities as a separate family, Sylviidae.

The second subfamily of flycatchers containing birds called warblers is the Melurinae, whose members are commonly known as Australian or wren warblers. These birds are found in Australia and as far east as Polynesia; they have cocked, wrenlike tails but brilliant colors.

The New World wood warblers usually have an unwarblerlike song and probably were named for their Old World counterparts because of their similar body shape, quick movements, and insectivorous habits. In addition to their songs, a prime difference between the New World wood warblers and the Old World warblers is that the former have nine primary feathers (flight feathers on the "hand") whereas the latter have ten.

The morning warblers are three species of African birds making up the genus Cichladusa in the thrush family, Turdidae.