''Melanophryniscus montevidensis'', also called Darwin's toad, is a species of

toad Toad is a common name for certain frogs, especially of the family Bufonidae, that are characterized by dry, leathery skin, short legs, and large bumps covering the parotoid glands. A distinction between frogs and toads is not made in scientif ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Bufonidae {{Cat main, Toad This category contains both species commonly called toads, and the true toads from the family Bufonidae {{Cat main, Toad This category contains both species commonly called toads, and the true toads from the family Bufonidae {{Cat m ...

and the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Melanophryniscus ''Melanophryniscus'' is a genus of toads in the family Bufonidae. They are found in northern half of Argentina, southern Bolivia, southern Brazil, Paraguay, and Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, Repúbl ...

found in

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

and

Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...

. Like other

amphibian Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...

s in its genus, its bright colors, defensive behavior, and rapid

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some inse ...

make it stand out. It also has a myriad of chemical compounds on its skin that could be used in biomedical applications.Langone, José A. (Mayo 2002).
Melanophryniscus, interesantes sapitos uruguayos
�. ''MUSEO NACIONAL DE HISTORIA NATURAL Y ANTROPOLOGIA'' (4). Consultado el 2023-06-22. Darwin's toad is jet black with yellow patches on its back, sides, forelimbs, and ventral. It has a red spot on the ventral side of the thigh and part of the abdomen. The palms of his hands and soles of its feet are also red.

Habitat and Behavior

The Darwin's toad's natural

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s are temperate

shrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It m ...

, intermittent freshwater

marsh A marsh is a wetland that is dominated by herbaceous rather than woody plant species.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p Marshes can often be found at ...

es, and sandy shores. This species can be found on the

coast The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in n ...

of the

Río de la Plata The Río de la Plata (, "river of silver"), also called the River Plate or La Plata River in English, is the estuary formed by the confluence of the Uruguay River and the Paraná River at Punta Gorda. It empties into the Atlantic Ocean and fo ...

and the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

, from Santiago Vázquez (Montevideo) to Praia da Alvorada (

Rio Grande do Sul Rio Grande do Sul (, , ; "Great River of the South") is a Federative units of Brazil, state in the South Region, Brazil, southern region of Brazil. It is the Federative_units_of_Brazil#List, fifth-most-populous state and the List of Brazilian st ...

). It is generally found in coastal sandbanks with psammophilous vegetation, preferring open areas with vegetation and, occasionally, flooded grasslands. It takes refuge in caves that it builds in the sand among the vegetation. The Darwin's toad is typically diurnal. It primarily feeds on ants, but will also eat small beetles, springtails and aphids. Its reproductive activity is short and usually occurs after heavy rains from late spring to early autumn. During the mating season, the males will act territorially. Their vocal repertoire changes and the males will have short fights. They can also be found in winter after heavy rains when the ambient temperature is above 15 °C (59 °F). When being held by hand, the specimens usually remain motionless with their belly up, displaying their red and yellow coloration. This defensive behavior has been called the Unken reflex.

Conservation Status

The Darwin's toad is considered a Critically Endangered (CR) species in

and globally Vulnerable (VU) due to

habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

from

urbanization Urbanization (or urbanisation) refers to the population shift from rural to urban areas, the corresponding decrease in the proportion of people living in rural areas, and the ways in which societies adapt to this change. It is predominantly t ...

of the areas where it lives. Some models predict a total disappearance of the climatic conditions where this species is distributed, which could cause its extinction by mid-century, due to its reproductive behavior being dependent on rainfall and temperatures in the warm months.

References

montevidensis Amphibians described in 1902 Taxonomy articles created by Polbot {{Bufonidae-stub