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''Acridotheres'' is a genus of starlings, the "typical" mynas, which are tropical members of the family Sturnidae. This genus has representatives in tropical southern Asia from Iran east to southern China and Indonesia. Two species have been introduced widely elsewhere. The common myna has been introduced to South Africa, Israel, Hawaii, North America, Australia and New Zealand, and the crested myna to the Vancouver region of British Columbia. The ''Acridotheres'' mynas are generally dark or dull birds with and fluted calls like most starlings; the sexes are similar. They walk rather than hop, and have modifications to the skull and its muscles for open bill probing. They resemble the hill mynas (''Gracula'') with which they often co-occur, in having large white or buff wing patches which are obvious in flight and in some also naked areas on the head, but differ in that only the head plumage is glossy, and the underparts tend to be paler. The naked head patches are different in arrangement. ''Acridotheres'' mynas are also much more terrestrial than ''Gracula''. They have bowing courtship displays, whereas ''Gracula'' has no visual display. They lay unmarked pale blue eggs. Several species have frontal crests which become covered with pollen when the birds take nectar from flowers, and may play a role in pollination. Like most starlings, the ''Acridotheres'' mynas are fairly omnivorous, eating fruit, nectar and insects. ==Systematics== Despite being both called "mynas", the ''Acridotheres'' mynas are closer related to a group of mainly terrestrial starlings from Eurasia, such as the common starling, and also African ones like the ''Lamprotornis'' glossy-starlings. Among these, they are among the larger and duller species; they seem to be one of the major groups to evolve most recently. Apparently, they all arose from ancestors which arrived from Central Asia and adapted to more humid conditions in the Tropics. They presumably were isolated in about their current range when the evolutionary radiation to which they belonged - including the wattled starling and the ''Sturnia'' species - was fragmented by desertification of their of origin at the start of the Early Pliocene, as Earth turned towards the last ice age 5 million years ago. The taxonomy of this group is complex, and other authorities differ considerably in which species they place in this genus, and in the species boundaries within ''Acridotheres''. The following is a list of "core" ''Acridotheres'' species in taxonomic order: *Great myna, ''Acridotheres grandis'' *Crested myna, ''Acridotheres cristatellus'' *Javan myna, ''Acridotheres javanicus'' *Pale-bellied myna, ''Acridotheres cinereus'' *Jungle myna, ''Acridotheres fuscus'' *Collared myna, ''Acridotheres albocinctus'' *Bank myna, ''Acridotheres ginginianus'' *Common myna, ''Acridotheres tristis'' The taxonomy of this group is complex, and other authorities differ considerably in which species they place in this genus, and in the species boundaries within ''Acridotheres''. Several species from the paraphyletic ''Sturnus'' assemblage are often placed in ''Acridotheres''. Indeed, as more recent studies suggest (Jønsson & Fjeldså 2006, Zuccon et al. 2006), this is most likely correct. *Vinous-breasted starling, ''Sturnus burmannicus'' *Black-winged starling, ''Sturnus melanopterus'' Two others (red-billed starling, ''Sturnus sericeus'' & white-cheeked starling, ''Sturnus cineraceus'') are probably basal in the group and might even be closer to ''Sturnia''. The relationships of the white-faced starling are more unclear, but it is generally not held to be close to the present genus. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Acridotheres」の詳細全文を読む スポンサード リンク
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