Toads | ||||||||||||
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Monte Verde Toad | ||||||||||||
Scientific classification | ||||||||||||
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Genera | ||||||||||||
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The true toads are the members of the Family Bufonidae in the Order Anura of amphibians. However a number of species in other families of Amphibia that are commonly referred to as toads. Although there are characteristics which distinguish frogs from toads in this broader sense, those distinctions do not form the basis for any broad scientific differentiation between the two.
The type species of the family Bufonidae is the Common Toad, Bufo bufo, and around it cluster a large number of species of the same genus, and some smaller genera. B. bufo is a tailless amphibian of stout build, with a warty skin, and any animal that shares these characteristic is liable to be called a toad, regardless of its location in formal taxonomy.
That the shape of the body is not a safe guide in judging of anuran groups is shown by certain species, such as Bufo jerboa, which has a very slender form and extremely long limbs, surpassing typical frogs, whilst on the other hand, some true frogs (Rana), adapted to burrowing habits, are absolutely toad-like. The Bufonidae include terrestrial, burrowing, thoroughly aquatic and arboreal types; Rhinophrynus, of Mexico, may be described as an anteater.
The genus Bufo embraces about 100 species, and is represented in nearly every part of the world except the Australian region (with the exception of the introduced Cane Toad (Bufo marinus), Madagascar, and nearly all other isolated islands.
Two species are found in the British Isles: the Common Toad, Bufo bufo, and the Natterjack Toad, Bufo calamita. The former is found almost everywhere. The Natterjack, which differs in its shorter limbs with nearly free toes (which are so short that the toad never hops but proceeds in a running gait) and in usually possessing orange/red warts, green eyes & a pale yellow line along the middle of the back, is local in England, the south-west of Scotland, and the west of Ireland. It is further remarkable for the very loud croak of the males, produced by a large vocal bladder on the throat which, when inflated, is larger than the head. Toads lay their eggs in long strings, forming double files in straight, jelly-like tubes.