the immature form of a frog is called a tadpole
pickerel_frog is frog. tadpole is larva. tadpole is not larva. short_footed_frog is not tree_frog. tailed_frog is frog. short_footed_frog is tree_frog. barking_frog is frog. grass_frog is true_frog. tongueless_frog is frog. pollywog is immature_frog.