Articles about the Myomorpha. The Myomorpha are a suborder with 1,524 species of rodents. It has almost a quarter of all mammal species. It has mice, rats, gerbils, hamsters, lemmings, and voles. They are grouped based on their jaws and molar teeth. Myomorphs are found throughout the world (except in Antarctica). They are in almost all habitats. They are usually nocturnal.