The common frog (Rana temporaria), also known as the European common frog, is a semi-aquatic amphibian found across much of Europe and parts of Asia, including Scandinavia and Japan. It typically inhabits terrestrial environments after undergoing three life stages: aquatic larva, terrestrial juvenile, and adult.
Common frogs have rounded bodies, webbed feet, and long hind legs suited for swimming and hopping. They differ from the common toad (Bufo bufo) by having longer legs and moist skin, while toadspawn is laid in long strings compared to frogspawn’s clumps.
Adults range from 6 to 9 cm in length, with colors varying from olive green to grey-brown. They can change color to blend in with their environment, and unusual colorations, like black or red, have been observed. Males are generally smaller than females and develop nuptial pads during the mating season, which turn their throats white.
The underbelly is typically white or yellow, sometimes speckled, while their eyes have transparent horizontal pupils and protective inner eyelids. Males are darker and often have a lighter overall color during mating, compared to the generally browner females.
