Edible frog

It is used for food, particularly in France for the delicacy frog legs. Females are between 5 and 9 cm (2.0 and 3.5 in) long, males between 6 and 11 cm (2.4 and 4.3 in).

This widespread and common frog has many common names, including European dark-spotted frog, European black-spotted pond frog, and European black-spotted frog.

Distribution

Pelophylax esculentus is endemic to Europe. It naturally occurs from the northern half of France to western Russia, and from Estonia and Denmark to Bulgaria and northern Italy. The edible frog is introduced in Spain,^[3] Norway^[4] and the United Kingdom.^[5] The natural range is nearly identical to that of P. lessonae.^[6]

Hybridogenesis

Pelophylax kl. esculentus is the fertile

Hybridogenesis implies that during gametogenesis hybrids (of RL genotype) exclude one parental genome (L or R) and produce gametes with an unrecombined genome of the other parental species (R or L, respectively), instead of containing mixed recombined parental genomes.^[8][9][11] The hybrid populations are usually propagated by mating (backcrosses) with a sympatric parental species – P. lessonae (LL) or P. ridibundus (RR) – providing the second, discarded parental genome (L or R respectively).^[8][9][11] Hybridogenesis is thus a hemiclonal mode of reproduction; half of the genome is transmitted to the next generation clonally, unrecombined (intact); the other half sexually, recombined.^[12][10][11]

For example, in the most widespread so called L–E system, edible frogs Pelophylax kl. esculentus (RE) produce gametes of the marsh frog P. ridibundus (R) and mate with coexisting pool frogs Pelophylax lessonae (L gametes) – see below in the middle.^[8][11]

Because this hybrid requires another taxon as a sexual host to reproduce, usually one of the parental species, it is a klepton^[13][14][15]. Hence the addition of the "kl." (for klepton) in the species name.^[16]

There are also known all-hybrid populations, where diploid hybrids (LR) coexist with triploid (LLR or LRR) hybrids, providing L or R genomes respectively. In this situation, diploid hybrids (LR) generate not only haploid R or L gametes, but also the diploid gametes (RL) needed to recreate triploids.^[8][9]

• 
  Swimming frog
• 
  Attempted copulation between two males
• 
  Example of cannibalism
• 
  Close-up of head
• 
  Head close-up, another perspective
• 
  Edible frog on a human arm
• 
  Edible frog in pond habitat
• 
  Edible frog in a swamp
• 
  Tadpole

References

External links

Wikimedia Commons has media related to Rana esculenta.

• ArchéoZooThèque : Edible frog skeleton drawing Archived 2019-09-13 at the Wayback Machine
• Species account on HerpFrance.com Archived 2015-09-24 at the Wayback Machine
• Video: Pool frogs and hybrid green frogs on YouTube. Mixed mating of pool frog and edible frog; pool frog are grass green and smaller.