Leaf-warblers are small insectivorousbirds belonging to the genusPhylloscopus. This was placed in the "wastebin" Old World warblerfamily, but is now moved into a new family Phylloscopidae (Alström et al. 2006). There are presently some 55 species in the genus, but this composition makes it polyphyletic with regards to Seicercus. Thus, several species will soon be moved out of the present genus.
These are active, constantly moving, warblers always associated with trees, though normally in fairly open woodland rather than tight plantations. They occur from top canopy to undershrubs. Most of the species are markedly territorial both in their summer and winter quarters.
Most are greenish or brownish above and off-white or yellowish below. Compared to some other "warblers", their songs are very simple
Species breeding in temperate regions are usually strongly migratory.
The species traditionally placed in Phylloscopus are:
Alström, Per; Ericson, Per G.P.; Olsson, Urban & Sundberg, Per (2006): Phylogeny and classification of the avian superfamily Sylvioidea. Molecular Phylogenetics and Evolution38(2): 381–397. doi:10.1016/j.ympev.2005.05.015
Badyaev Alexander V. & Leaf, Elizabeth S. (1997): Habitat associations of song characteristics in Phylloscopus and Hippolais warblers. Auk114(1): 40-46. PDF fulltext
Del Hoyo, J.; Elliot, A. & Christie D. (editors). (2006). Handbook of the Birds of the World. Volume 11: Old World Flycatchers to Old World Warblers. Lynx Edicions. ISBN 849655306X.