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''Buteogallus'' is a genus of bird of prey in the family Accipitridae. All members of this genus are essentially Neotropical, but the distribution of a single species extends slightly into the extreme southwestern USA. Many of the species are fond of large crustaceans and even patrol long stretches of shore or riverbank on foot where such prey abounds, but some have a rather different lifestyle. Most of the species have a characteristic tail pattern. This consists of a black base, a wide white middle band, a wide black band, and a quite narrow white band on the feathertips that is often hard to discern or may be lost when the feathers are very worn. Only the white-necked hawk and the rufous crab hawk have a very different tail patterns (see also below). ==Systematics and taxonomy== This genus contains the following species, ordered according to putative relatedness: * Slate-coloured hawk ''Buteogallus schistaceus'' * White-necked hawk ''Buteogallus lacernulatus'' * Rufous crab hawk, ''Buteogallus aequinoctialis'' * Common black hawk, ''Buteogallus anthracinus'' * * Mangrove black hawk, ''Buteogallus (anthracinus) subtilis'' – formerly considered a distinct species, but now considered a subspecies. * Cuban black hawk, ''Buteogallus gundlachii'' – formerly included in ''B. anthracinus'' * Great black hawk, ''Buteogallus urubitinga'' * Savanna hawk, ''Buteogallus meridionalis'' * Crowned solitary eagle, ''Buteogallus coronatus'' * Montane solitary eagle, ''Buteogallus solitarius'' The solitary eagles (formerly ''Harpyhaliaetus'') are a more inland relative of the "black" group of ''Buteogallus'' – in phenotype they are essentially hefty common black-hawks with lighter body plumage and in one species a small crest. Insofar as there are differences in anatomy, these seem to be related to the different prey they hunt (namely reptiles). Together with the savanna hawk, they seem to be close to some species that were uncomfortably placed in ''Leucopternis''. As that genus was apparently polyphyletic, the present article follows a proposal to unite the solitary eagles as well as the slate-coloured hawk (''"Leucopternis" schistaceus'') with ''Buteogallus'', to agree with the morphological and mtDNA sequence data., with the addition of the white-necked hawk, ''"Leucopternis" lacernulatus''. For a long time various systematists have proposed moving the slate-coloured hawk to ''Buteogallus''. Together with the crab hawks and solitary eagles form a sequence of plumage patterns that nicely agrees with the DNA-based phylogeny: the slate-coloured hawk looks very much like a smaller, shorter-legged and lighter common black hawk. The case of the white-necked hawk is more puzzling. It is visually and ecologically almost identical to the sympatric mantled hawk (''Leucopternis polionotus'') and some allopatric white hawks (''L. albicollis'') but differs in tail color. According to the mtDNA data, it is very closely related to the savanna hawk, which is visually dissimilar, appearing like a very light ''Buteogallus'' which has an ochre-grey coloration due to abundant pheomelanins. Either there has been strong convergent evolution in plumage and ecology - perhaps a case of mimicry - between the white-necked and the mantled hawks, or the mtDNA data is misleading due to ancient hybrid introgression. In the respect, it is interesting to note that the white-necked hawk specimen sampled showed indications of heteroplasmy.〔 The placement of the peculiarly apomorphic rufous crab hawk in regard to all these birds must be considered unresolved for the time being.〔 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「Buteogallus」の詳細全文を読む スポンサード リンク
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