Tettigoniidae are commonly called katydids or bush crickets. There are more than 6,400 species. They are also known as long-horned grasshoppers, although they are more closely related to crickets and weta than to any type of grasshopper. The name is derived from the genus Tettigonia, first described by Carl Linnaeus in 1748. Part of the suborder Ensifera, it is the only family in the superfamily Tettigonioidea. Many tettigoniids exhibit mimicry and camouflage, commonly with shapes and colors similar to leaves.
Tettigoniids may be distinguished from the grasshopper by the length of their filamentous antennae, which may exceed their own body length, while grasshoppers' antennae are always relatively short and thickened.
True Katydids eat leaves of most deciduous (lose leaves in Fall) trees and shrubs, especially oaks.
Katydids can fly short distances when threatened, but they prefer to walk and climb. When they do fly, it is more of a downward flutter. If a katydid lands on the ground, it will walk to the nearest tree and climb.