Grass-warbler

The grass-warblers are small passerine birds belonging to the genus Locustella. Formerly placed in the paraphyletic "Old World warbler" assemblage, they are now considered the northernmost representatives of a largely Gondwanan family, the Locustellidae.

These are rather drab brownish "warblers" usually associated with fairly open grassland, shrubs or marshes. Some are streaked, others plain, all are difficult to view. They are insectivorous.

The most characteristic feature of this group is that the song of several species is a mechanical insect-like reeling which gives rise to the group's scientific name.

Species breeding in temperate regions are strongly migratory.

The nine species are:
 * Gray's Grasshopper-warbler, Locustella fasciolata
 * Sakhalin Grasshopper-warbler, Locustella amnicola
 * Marsh Grassbird, Locustella pryeri
 * Pallas's Grasshopper-warbler, Locustella certhiola
 * Middendorf's Grasshopper-warbler, Locustella ochotensis
 * Styan's Grasshopper-warbler, Locustella pleskei
 * Lanceolated Warbler, Locustella lanceolata
 * River Warbler, Locustella fluviatilis
 * Savi's Warbler, Locustella luscinoides 
 * Brown Bush-warbler, Locustella luteoventris
 * Chinese Bush-warbler, Locustella tacsanowskia
 * Common Grasshopper-warbler, Locustella naevia
 * Long-billed Bush-warbler, ''Locustella major
 * Chestnut-backed Bush-warbler, ''Locustella castanea
 * Long-tailed Bush-warbler, ''Locustella caudata
 * Friendly Bush-warbler, ''Locustella accentor
 * Baikal Bush-warbler, ''Locustella davidi
 * Spotted Bush-warbler, ''Locustella thoracica
 * West Himalayan Bush-warbler, ''Locustella kashmirensis
 * Taiwan Bush-warbler, ''Locustella alishanensis
 * Russet Bush-warbler, ''Locustella mandelli
 * Benguet Bush-warbler, ''Locustella seebohmi
 * Javan Bush-warbler, ''Locustella montis
 * Timor Bush-warbler, ''Locustella timorensis

A fossil acrocoracoid from the Late Miocene (about 11 mya) of Rudabánya (NE Hungary) is quite similar to this bone in the present genus (Bernor et al. 2002). Given its rather early age (most Passerida genera are not known until the Pliocene), it is not too certain that it is correctly placed here, but it is highly likely to belong to the Megaluridae at the least. As the grass-warblers are the only known megalurid warblers from Europe, it is still quite likely that the bone piece belongs to a basal Locustella.