The ''Acrocephalus'' warblers are small, insectivorous

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped'), which includes more than half of all bird species. Sometimes known as perching birds, passerines are distinguished from other orders of birds by th ...

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...

s belonging to the genus ''Acrocephalus''. Formerly in the

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

Old World warbler Old World warblers are a large group of birds formerly grouped together in the bird family Sylviidae. The family held over 400 species in over 70 genera, and were the source of much taxonomic confusion. Two families were split out initially, the ci ...

assemblage, they are now separated as the namesake of the marsh and tree warbler family

Acrocephalidae The Acrocephalidae (the reed warblers, marsh- and tree-warblers, or acrocephalid warblers) are a family of oscine passerine birds, in the superfamily Sylvioidea. The species in this family are usually rather large "warblers". Most are rather p ...

. They are sometimes called marsh warblers or reed warblers, but this invites confusion with

marsh warbler The marsh warbler (''Acrocephalus palustris'') is an Old World warbler currently classified in the family Acrocephalidae. It breeds in temperate Europe and the western Palearctic and winters mainly in southeast Africa. It is notable for incorpora ...

and

reed warbler 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 famil ...

proper, especially in North America, where it is common to use lower case for bird species. These are rather drab brownish warblers usually associated with

marsh A marsh is a wetland that is dominated by herbaceous rather than woody plant species.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p Marshes can often be found a ...

es 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 The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

. This in turn has led to many of the resulting insular

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

species to become

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...

. Several of these species (including all but one of the species endemic to the Marianas and two endemic to

French Polynesia )Territorial motto: ( en, "Great Tahiti of the Golden Haze") , anthem = , song_type = Regional anthem , song = "Ia Ora 'O Tahiti Nui" , image_map = French Polynesia on the globe (French Polynesia centered).svg , map_alt = Location of French ...

) have already gone extinct. The most enigmatic species of the genus, the

large-billed reed warbler The large-billed reed warbler (''Acrocephalus orinus'') is an Old World warbler in the genus '' Acrocephalus''. The species has been dubbed as "the world's least known bird". It was known from a single specimen collected in India in 1867 and redi ...

(''A. orinus''), was rediscovered in

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...

in March, 2006; it was found also in a remote corner of

Afghanistan Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bord ...

in the summer of 2009. Prior to these recent sightings, it had been found only once before, in 1867. Many species have a flat head profile, which gives rise to the group's scientific name. The genus name ''Acrocephalus'' is from

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...

''akros'', "highest", and ''kephale'', "head". It is possible that Naumann and Naumann thought ''akros'' meant "sharp-pointed".

List of species in taxonomic order

The genus contains 42 species of which 6 insular forms are now extinct: *

Basra reed warbler The Basra reed warbler (''Acrocephalus griseldis'') is a "warbler" of the genus '' Acrocephalus''. It is an endemic breeder in Southwestern Iran, East and southern Iraq, Kuwait, and Israel in extensive beds of papyrus and reeds. It is easily mis ...

, ''Acrocephalus griseldis'' * Cape Verde warbler, ''Acrocephalus brevipennis'' * Greater swamp warbler, ''Acrocephalus rufescens'' *

Lesser swamp warbler The lesser swamp warbler or Cape reed warbler (''Acrocephalus gracilirostris'') is an Old World warbler in the genus '' Acrocephalus''. It is a resident breeder in Africa from the Democratic Republic of the Congo, the Chad and Ethiopia south t ...

, ''Acrocephalus gracilirostris'' *

Madagascar swamp warbler The Madagascar swamp warbler (''Acrocephalus newtoni'') is a species of Old World warbler in the family Acrocephalidae. It is found only in Madagascar. Its natural habitat is swamp A swamp is a forested wetland.Keddy, P.A. 2010. Wetland Ec ...

, ''Acrocephalus newtoni'' * Seychelles warbler, ''Acrocephalus sechellensis'' * Rodrigues warbler, ''Acrocephalus rodericanus'' *

Great reed warbler The great reed warbler (''Acrocephalus arundinaceus'') is a Eurasian passerine in the genus '' Acrocephalus''. The genus name ''Acrocephalus'' is from Ancient Greek ''akros'', "highest", and ''kephale'', "head". It is possible that Naumann and N ...

, ''Acrocephalus arundinaceus'' *

Oriental reed warbler The Oriental reed warbler (''Acrocephalus orientalis'') is a passerine bird of eastern Asia belonging to the reed warbler genus '' Acrocephalus''. It was formerly classified as a subspecies of the great reed warbler (''A. arundinaceus'') of the ...

, ''Acrocephalus orientalis'' * Clamorous reed warbler, ''Acrocephalus stentoreus'' *

Australian reed warbler The Australian reed warbler (''Acrocephalus australis'') is an Old World warbler in the genus '' Acrocephalus'' and is the only ''Acrocephalus'' species native to Australia. It has also been observed in Papua New Guinea and nearby islands. The ...

, ''Acrocephalus australis'' *

Millerbird The millerbird (''Acrocephalus familiaris'') is a species of Old World warbler in the family Acrocephalidae endemic to the Hawaiian Islands. Taxonomy It has two subspecies, ''A. f. kingi'' and ''A f. familiaris''. The nominate subspecies, the ...

, ''Acrocephalus familiaris'' *† Nightingale reed warbler, ''Acrocephalus luscinius'' * Saipan reed warbler, ''Acrocephalus hiwae'' *† Aguiguan reed warbler, ''Acrocephalus nijoi'' *† Pagan reed warbler, ''Acrocephalus yamashinae'' *†

Mangareva reed warbler The Mangareva reed warbler or Astrolabe reed warbler (''Acrocephalus astrolabii'') is a presumed extinct songbird that existed on Mangareva in the Gambier Islands. It is known from only two specimens, and is believed to have gone extinct in the m ...

, ''Acrocephalus astrolabii'' * Nauru reed warbler, ''Acrocephalus rehsei'' * Caroline reed warbler, ''Acrocephalus syrinx'' * Bokikokiko, ''Acrocephalus aequinoctialis'' * Northern Marquesan reed warbler, ''Acrocephalus percernis'' * Tahiti reed warbler, ''Acrocephalus caffer'' *† Moorea reed warbler, ''Acrocephalus longirostris'' *†

Garrett's reed warbler Garrett's reed warbler (''Acrocephalus musae''), sometimes called Society Islands reed warbler or Forster's reed-warbler was a songbird in the genus '' Acrocephalus''. Formerly placed in the "Old World warbler" assemblage (Sylviidae), it is now i ...

, ''Acrocephalus musae'' *

Southern Marquesan reed warbler The southern Marquesan reed warbler (''Acrocephalus mendanae'') is a species of Old World warbler in the family Acrocephalidae. It was formerly considered conspecific with the northern Marquesan reed warbler, and together known as the Marquesa ...

, ''Acrocephalus mendanae'' *

Tuamotu reed warbler The Tuamotu reed warbler (''Acrocephalus atyphus'') is a species of Old World warbler in the family Acrocephalidae. It is found only in French Polynesia )Territorial motto: ( en, "Great Tahiti of the Golden Haze") , anthem = , song_type = Re ...

, ''Acrocephalus atyphus'' *

Cook reed warbler The Cook reed warbler (''Acrocephalus kerearako'') or Cook Islands reed warbler, is a species of Old World warbler in the family Acrocephalidae. It is native to the southeastern Cook Islands. Its natural habitats are subtropical or tropical dry f ...

, ''Acrocephalus kerearako'' * Rimatara reed warbler, ''Acrocephalus rimatarae'' * Henderson reed warbler, ''Acrocephalus taiti'' * Pitcairn reed warbler, ''Acrocephalus vaughani'' * Black-browed reed warbler, ''Acrocephalus bistrigiceps'' * Moustached warbler, ''Acrocephalus melanopogon'' *

Aquatic warbler The aquatic warbler (''Acrocephalus paludicola'') is an Old World warbler in the genus '' Acrocephalus''. It breeds in temperate eastern Europe and western Asia, with an estimated population of 11,000-15,000 pairs. It is migratory, wintering ...

, ''Acrocephalus paludicola'' *

Sedge warbler The sedge warbler (''Acrocephalus schoenobaenus'') is an Old World warbler in the genus '' Acrocephalus''. It is a medium-sized warbler with a brown, streaked back and wings and a distinct pale supercilium. Sedge warblers are migratory, crossing ...

, ''Acrocephalus schoenobaenus'' * Speckled reed warbler, ''Acrocephalus sorghophilus'' * Blunt-winged warbler, ''Acrocephalus concinens'' * Manchurian reed warbler, ''Acrocephalus tangorum'' (sometimes included in ''A. agricola'') *

Large-billed reed warbler The large-billed reed warbler (''Acrocephalus orinus'') is an Old World warbler in the genus '' Acrocephalus''. The species has been dubbed as "the world's least known bird". It was known from a single specimen collected in India in 1867 and redi ...

, ''Acrocephalus orinus'' * Paddyfield warbler, ''Acrocephalus agricola'' * Blyth's reed warbler, ''Acrocephalus dumetorum'' * Common reed warbler, ''Acrocephalus scirpaceus'' *

Marsh warbler The marsh warbler (''Acrocephalus palustris'') is an Old World warbler currently classified in the family Acrocephalidae. It breeds in temperate Europe and the western Palearctic and winters mainly in southeast Africa. It is notable for incorpora ...

, ''Acrocephalus palustris'' Fragmentary

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

remains from the

Late Miocene The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene Epoch made up of two stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma (million years ago) to 5.333 Ma. The ...

(about 11 mya) of

Rudabánya Rudabánya is a town in Borsod-Abaúj-Zemplén county, Hungary. The town territory was the location of the discovery of a hominid from 12 million years ago, '' Dryopithecus brancoi'' (1969). International relations Rudabánya is twinned Twinni ...

(NE

Hungary Hungary ( hu, Magyarország ) is a landlocked country in Central Europe. Spanning of the Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croa ...

) show some

apomorph In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to hav ...

ies typical of this genus. Given its rather early age (most

Passerida Passerida is, under the Sibley-Ahlquist taxonomy, one of two parvorders contained within the suborder Passeri (standard taxonomic practice would place them at the rank of infraorder). While more recent research suggests that its sister parvorde ...

genera are not known until the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Acrocephalus videos
on the Internet Bird Collection {{Taxonbar, from=Q637716 Bird genera Taxa named by Johann Andreas Naumann Taxa named by Johann Friedrich Naumann