The edible frog (Rana kl. esculenta) is a name for the common European frog. It is often used for food, particularly in France for the delicacy Frogs' legs. Females are between 5 to 9 cm long, males between 6 to 11 cm.
Rana esculenta is a hybrid between Pool Frog (Rana lessonae) and the Marsh Frog (Rana ridibunda), hence the addition of the kl. (for klepton) in the species name. During the ice ages the population of the common ancestor of both species was separated. Both developed into one species, but stayed genetically close enough to be able to create fertile hybrids. However when edible frogs mate with each other, their offsprings are often misformed, so a pure population of edible frogs cannot survive. In nature the female edible frogs usually mate with males of one of the other two species to keep the hybrid population alive, leaving the male edible frogs without descendents.