The marsh frog (Pelophylax ridibundus) is the largest frog native to Europe and belongs to the family of true frogs. It is very similar in appearance to the closely related edible frog and pool frog. These three species, now again in the genus Pelophylax, are often referred to as "green frogs" to distinguish them from the more terrestrial European Rana species, which are known as "brown frogs" (best exemplified by the common frog Rana temporaria).