True toad

or European toad, Bufo bufo. and male on her back. A true toad is any member of the family Bufonidae, in the order Anura (frogs and toads). This is the only family of anurans in which all members are known as toads, although some may be called frogs (such as harlequin frogs). The bufonids now comprise more than 35 genera, Bufo being the best known.

or European toad, Bufo bufo.]] and male on her back.]] A true toad is any member of the family Bufonidae, in the order Anura (frogs and toads). This is the only family of anurans in which all members are known as toads, although some may be called frogs (such as harlequin frogs). The bufonids now comprise more than 35 genera, Bufo being the best known.

Characteristics

True toads are widespread and are native to every continent except Australia and Antarctica, inhabiting a variety of environments, from arid areas to rainforest. Most lay eggs in paired strings that hatch into tadpoles, although, in the genus Nectophrynoides, the eggs hatch directly into miniature toads. All true toads are toothless and generally warty in appearance. They have a pair of parotoid glands on the back of their heads. These glands contain an alkaloid poison which the toads excrete when stressed. The poison in the glands contains a number of toxins causing different effects. Bufotoxin is a general term. Different animals contain significantly different substances and proportions of substances. Some, like the cane toad Rhinella marina, are more toxic than others. Some "psychoactive toads", such as the Colorado River toad Incilius alvarius, have been used recreationally for the effects of their bufotoxin. Depending on the species, male or female toads may possess a Bidder's organ, a trait unique to all bufonids except genera Melanophryniscus and Truebella. Under the right conditions, the organ becomes an active ovary. The loss of teeth has arisen in frogs independently over 20 times. Notably, all members of Bufonidae are toothless. Another Anuran family with a comparable degree of edentulism is the family Microhylidae.

Reproduction

Internal fertilization occurs in four bufonid genera. Mertensophryne (some species) Nectophrynoides (presumably all species) Altiphrynoides malcolmi (one out of two species in the genus Altiphrynoides) Nimbaphrynoides occidentalis (the sole species in the monotypic genus Nimbaphrynoides) Ascaphus (all species) and Eleutherodactylus (two species, E. coqui and E. jasperi) are the only other frog genera that have internal fertilization. Limnonectes larvaepartus also has internal fertilization.

Taxonomy and genera

The family Bufonidae contains over 570 species among 52 genera. The family also contains an incertae sedis species, "Bufo" scorteccii .

References

Stebbins, Robert. Western Reptiles & Amphibians (3rd ed.). Houghton Mifflin Co., 2003. Halliday, Tim R., and Kraig Adler (editors). The New Encyclopedia of Reptiles & Amphibians. Facts on File, New York, 2002.

External links

Tolweb.org: Bufonidae Bufonidae.com Amphibian and Reptiles of Peninsular Malaysia - Family Bufonidae FED.us Bufonidae recordings from the British Library Sound Archive

Text derived from https://en.wikipedia.org/w/index.php?oldid=1355281699 under CC BY-SA 4.0; modifications have been made.