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| synonyms_ref = 〔 | range_map = Bufo bufo distribution.png | range_map_width = 240px | range_map_caption = Range map of common toad }} The common toad, European toad or in Anglophone parts of Europe, simply the toad (''Bufo bufo'', from Latin ''bufo'' "toad"), is an amphibian found throughout most of Europe (with the exception of Ireland, Iceland, and some Mediterranean islands), in the western part of North Asia, and in a small portion of Northwest Africa. It is one of a group of closely related animals that are descended from a common ancestral line of toads and which form a species complex. The toad is an inconspicuous animal as it usually lies hidden during the day. It becomes active at dusk and spends the night hunting for the invertebrates on which it feeds. It moves with a slow ungainly walk or short jumps and has greyish brown skin covered with wart-like lumps. Although toads are usually solitary animals, in the breeding season, large numbers of toads converge on certain breeding ponds, where the males compete to mate with the females. Eggs are laid in gelatinous strings in the water and later hatch out into tadpoles. After several months of growth and development, these sprout limbs and undergo metamorphosis into tiny toads. The juveniles emerge from the water and remain largely terrestrial for the rest of their lives. The common toad seems to be in decline in part of its range but overall is listed as being of "least concern" in the IUCN Red List of Threatened Species.〔 It is threatened by habitat loss, especially by drainage of its breeding sites, and some toads get killed on the roads as they make their annual migrations. It has long been associated in popular culture and literature with witchcraft. == Taxonomy == The common toad was first given the name ''Rana bufo'' by the Swedish biologist Carl Linnaeus in the 10th edition of Systema Naturae in 1758. In this work, he placed all the frogs and toads in the single genus ''Rana''. It later became apparent that this genus should be subdivided, and in 1768, the Austrian naturalist Josephus Nicolaus Laurenti placed the common toad in the genus ''Bufo'', naming it ''Bufo bufo''. The toads in this genus are included in the family Bufonidae, the true toads. Various subspecies of ''Bufo bufo'' have been recognized over the years. The Caucasian toad is found in the mountainous regions of the Caucasus and was at one time classified as ''Bufo bufo verrucosissima''. It has a larger genome and differs from ''Bufo bufo'' morphologically 〔 and is now accepted as ''Bufo verrucosissimus''. The spiny toad was classified as ''Bufo bufo spinosus''. It is found in the Mediterranean area and grows to a larger size and has a spinier skin than its more northern counterparts with which it intergrades. It is now accepted as ''Bufo spinosus''.〔(【引用サイトリンク】title=''Bufo spinosus'' )〕 The Gredos toad, ''Bufo bufo gredosicola'', is restricted to the Sierra de Gredos, a mountain range in central Spain. It has exceptionally large paratoid glands and its colour tends to be blotched rather than uniform. It is now considered to be a synonym of ''Bufo spinosus''. ''Bufo bufo'' is part of a species complex, a group of closely related species which cannot be clearly demarcated.〔 Several modern species are believed to form an ancient group of related taxa from preglacial times. These are the spiny toad (''Bufo spinosus''), the Caucasian toad (''Bufo verrucosissimus'') and the Japanese common toad (''Bufo japonicus''). The European common toad (''Bufo bufo'') seems to have arisen more recently. It is believed that the range of the ancestral form extended into Asia but that isolation between the eastern and western species complexes occurred as a result of the development of the Central Asian Deserts during the Middle Miocene. The exact taxonomic relationships between these species remains unclear.〔 A serological investigation into toad populations in Turkey undertaken in 2001 examined the blood serum proteins of ''Bufo verrucosissimus'' and ''Bufo spinosus''. It found that the differences between the two were not significant and that therefore the former should be synonymized with the latter. A study published in 2012 examined the phylogenetic relationships between the Eurasian and North African species in the ''Bufo bufo'' group and indicated a long evolutionary history for the group. Nine to thirteen million years ago, ''Bufo eichwaldi'', a recently described species from south Azerbaijan and Iran, split from the main lineage. Further divisions occurred with ''Bufo spinosus'' splitting off about five million years ago when the Pyrenees were being uplifted, an event which isolated the populations in the Iberian Peninsula from those in the rest of Europe. The remaining European lineage split into ''Bufo bufo'' and ''Bufo verrucosissimus'' less than three million years ago during the Pleistocene. Very occasionally the common toad hybridizes with the natterjack toad (''Bufo calamita'') or the European green toad (''Bufo viridis''). 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「common toad」の詳細全文を読む スポンサード リンク
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