Katydids are called katydids in northern China. They are the larger species of song insects, with a body length of about 40 mm. The body is mostly grass green, and some are gray or dark gray. The wings are membranous. Fragile, with the leading edge sloping downward, usually with the left wing overlying the right wing. Only the male katydids can make sounds, the females are dumb, but the females have earphones and can hear the calls of the males.