Old World flycatchers are a large group of small passerine birds native to the Old World. They are mainly small arboreal insectivores. The appearance of these birds is very varied, but they mostly have weak songs and harsh calls. There are 274 species worldwide and 31 species which occur in Iran.
The wheatears, genus Oenanthe, were formerly considered to be members of the thrush family Turdidae. They are more commonly now placed in the flycatcher family Muscicapidae. This is an Old World group, but the Northern Wheatear has established a foothold in eastern Canada and Greenland.
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