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The Proboscidea (from the Greek and the Latin ''proboscis'') are a taxonomic order of afrotherian mammals containing one living family, Elephantidae, and several extinct families. This order, first described by J. Illiger in 1811, encompasses the trunked mammals.〔(【引用サイトリンク】title=Proboscidea )〕 Later proboscideans are distinguished by tusks and long, muscular trunks; these features are less developed or absent in early proboscideans. Proboscideans may have produced the largest land mammals of all time in the form of ''Palaeoloxodon namadicus'' and ''Mammut borsoni'', which weighed around 24 tons and reached shoulder heights of over 5 meters, surpassing several sauropod dinosaurs. The earliest known proboscidean is ''Eritherium'', followed by ''Phosphatherium'', a small animal about the size of a fox. These both date from late Paleocene deposits of Morocco. Proboscideans diversified during the Eocene and early Oligocene. Several primitive families from these epochs have been described, including Numidotheriidae, Moeritheriidae, and Barytheriidae in Africa. (Anthracobunidae from the Indian subcontinent has also been included, but was excluded from Proboscidea by Shoshani & Tassy (2005)〔 and has more recently been assigned to Perissodactyla.) These were followed by the earliest Deinotheriidae, or "hoe tuskers", which thrived during the Miocene and into the early Quaternary. Proboscideans from the Miocene also included ''Stegolophodon'', an early genus of the disputed family Stegodontidae; the diverse family of Gomphotheriidae, or "shovel tuskers", such as ''Platybelodon'' and ''Amebelodon''; and the Mammutidae, or mastodons. Most families of Proboscidea are now extinct, many since the end of the last glacial period. Recently extinct species include the last examples of gomphotheres in Central and South America, the American mastodon of family Mammutidae in North America, numerous stegodonts once found in Asia, the last of the mammoths, and several island species of dwarf elephants. The classification of proboscideans is unstable and frequently revised, and some relationships within the order remain unclear. As of 2005, at least 177 species and subspecies of proboscideans, classified in 43 genera, are recognized; the order is summarized as: :Proboscidea ::''incertae sedis'' †Moeritheriidae :::†''Moeritherium'' ::†Plesielephantiformes :::†Numidotheriidae :::†Barytheriidae :::†Deinotheriidae ::Elephantiformes :::''incertae sedis'' †''Hemimastodon'' :::†Palaeomastodontidae :::†Phiomiidae :::Elephantimorpha ::::''incertae sedis ''†''Eritreum'' ::::†Mammutida (mastodons) :::::†Mammutoidea ::::::†Mammutidae ::::Elephantida :::::†Gomphotherioidea ::::::†Gomphotheriidae (gomphotheres) :::::Elephantoidea ::::::''incertae sedis'' †''Tetralophodon'' ::::::''incertae sedis'' †''Morrillia'' ::::::''incertae sedis'' †''Anancus'' ::::::''incertae sedis'' †''Paratetralophodon'' ::::::†Stegodontidae ::::::Elephantidae :::::::†Stegotetrabelodontinae ::::::::†''Stegotetrabelodon'' ::::::::†''Stegodibelodon'' :::::::Elephantinae (elephants and mammoths) ::::::::†''Primelephas'' ::::::::Loxodontini :::::::::''Loxodonta'' ::::::::Elephantini :::::::::†''Palaeoloxodon'' :::::::::''Elephas'' :::::::::†''Mammuthus'' ==References== 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「proboscidea」の詳細全文を読む スポンサード リンク
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