| Acrocephalus | |
|---|---|
| |
| Great reed warbler, Acrocephalus arundinaceus | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Passeriformes |
| Family: | Acrocephalidae |
| Genus: | Acrocephalus J. A. Naumann and J. F. Naumann, 1811 |
| Type species | |
| Turdus arundinaceus[1] Linnaeus, 1758
| |
| Species | |
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See text | |
The Acrocephalus warblers are small, insectivorous passerine birds belonging to the genus Acrocephalus. Formerly in the paraphyletic Old World warbler assemblage, they are now separated as the namesake of the marsh and tree warbler family Acrocephalidae. They are sometimes called marsh warblers or reed warblers, but this invites confusion with marsh warbler and reed warbler.
These are rather drab brownish warblers usually associated with marshes or other wetlands. Some are streaked, others plain. Many species breeding in temperate regions are migratory.
This genus has heavily diversified into many species throughout islands across the tropical Pacific. This in turn has led to many of the resulting insular endemic species to become endangered. Several of these species (including all but one of the species endemic to the Marianas and two endemic to French Polynesia) have already gone extinct.
The most enigmatic species of the genus, the large-billed reed warbler (A. orinus), was rediscovered in Thailand in March, 2006; it was found also in a remote corner of Afghanistan in the summer of 2009. Prior to these recent sightings, it had been found only once before, in 1867.
The genus Acrocephalus was introduced in 1811 by the German naturalist Johann Andreas Naumann and his son Johann Friedrich Naumann.[2][3] The type species was designated as Turdus arundinaceus Linnaeus, 1758, by the English zoologist George Gray in 1840. This is the great reed warbler.[4][5] Many species have a flat head profile, which gives rise to the genus name, Acrocephalus from Ancient Greek akros, "highest", and kephale, "head". It is possible that the Naumanns thought akros meant "sharp-pointed".[6]
The genus contains 42 species of which 6 insular forms are now extinct:[7]
Fragmentary fossil remains from the Late Miocene (about 11 mya) of Rudabánya (NE Hungary) show some apomorphies typical of this genus.[8] 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 Acrocephalidae at the least.
