About Melanophryniscus montevidensis (Philippi, 1902)
Melanophryniscus montevidensis, commonly known as Darwin's toad, is a species of toad in the family Bufonidae, belonging to the genus Melanophryniscus. It is found in Brazil and Uruguay. Like other amphibians in its genus, it is set apart by its bright coloration, defensive behavior, and rapid metamorphosis. Its skin contains a wide range of chemical compounds that may be suitable for biomedical applications. Darwin's toad is jet black, with yellow patches on its back, sides, forelimbs, and ventral surface. It has a red spot on the ventral side of the thigh and part of the abdomen; the palms of its hands and soles of its feet are also red. Darwin's toad's natural habitats are temperate shrubland, intermittent freshwater marshes, and sandy shores. This species occurs along the coast of the Río de la Plata and the Atlantic Ocean, ranging from Santiago Vázquez in Montevideo to Praia da Alvorada in Rio Grande do Sul. It is most often found in coastal sandbanks with psammophilous vegetation, where it prefers open, vegetated areas, and is occasionally found in flooded grasslands. It takes shelter in burrows it digs in the sand among vegetation. Darwin's toad is typically diurnal. It feeds mainly on ants, but will also consume small beetles, springtails, and aphids. Its reproductive period is short, and usually takes place after heavy rains from late spring to early autumn. During the mating season, males defend territories. Their vocal repertoire changes, and males engage in short fights with one another. They can also be found active in winter after heavy rains, when the air temperature is above 15 °C (59 °F). When handled by humans, individual toads usually stay motionless with their belly turned upward, displaying their red and yellow coloration. This defensive behavior is known as the Unken reflex.
