In places where they were introduced, marsh frogs may pose a threat to the native Pelophylax by diluting the gene pool, but there is evidence that although they may hybridize they do not affect the overall population that greatly. References External links Listen to Pelophylax ridibundus call sound Pelophylax Amphibians of Afghanistan Amphibians of Iran Amphibians of the Middle East Vertebrates of the Arabian Peninsula Amphibians of Europe Amphibians described in 1771 Taxa named by Peter Simon Pallas