Larva Larva A larva (plural: "larvae" ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The larva's appearance is generally very different from the adult form ("e.g." caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. Larvae are frequently adapted to environments separate from adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water
Couch's spadefoot toad used by the toads to burrow into the ground to prevent water loss and hide from predators. There are two spadefoot species in the Sonoran Desert of Arizona and California. Couch's spadefoot toad ("Scaphiopus couchi") has a sickle-shaped "spade", whereas the western spadefoot toad ("Spea hammondii") has a rounded "spade". Spadefoots are not true toads and should therefore simply be called spadefoots. Couch's spadefoot toad is native to the United States southwest of southeastern Colorado and central Oklahoma, northern Mexico and the Baja peninsula. They can be found throughout the Sonoran Desert, which includes parts of southern Arizona and California.