 For the purpose of reproduction most amphibians require fresh water although some lay their eggs on land and have developed various means of keeping them moist . A few ( e.g. <unk> raja ) can inhabit brackish water , but there are no true marine amphibians . There are reports , however , of particular amphibian populations unexpectedly invading marine waters . Such was the case with the Black Sea invasion of the natural hybrid Pelophylax esculentus reported in 2010 . 
