''Trachycephalus quadrangulum'', the Chocoan milk frog, is a species of

frog A frog is any member of a diverse and largely semiaquatic group of short-bodied, tailless amphibian vertebrates composing the order (biology), order Anura (coming from the Ancient Greek , literally 'without tail'). Frog species with rough ski ...

in the family

Hylidae Hylidae is a wide-ranging family of frogs commonly referred to as " tree frogs and their allies". However, the hylids include a diversity of frog species, many of which do not live in trees, but are terrestrial or semiaquatic. Taxonomy and ...

. It is endemic to the Pacific slopes of the

Andes The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...

Ecuador Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...

and

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

. Scientists have seen it between 20 and 350 meters above sea level. The adult male frog measures 53.4 to 76.9 mm in snout-vent length and the adult female frog 60.5 to 80.8 mm. The adult frog is brown or gray in color with a four-sided darker gray mark on its back. Its head is wider than it is long.

References

Frogs of South America Amphibians described in 1882 Trachycephalus Taxa named by George Albert Boulenger {{Hylidae-stub