The family Tettigoniidae includes species that are often referred to as katydids, or longhorn grasshoppers. Just two genera occur in New Zealand, both closely related to Australian species.

The large leaf shaped katydid Caedicia simplex is found most often on native and introduced shrubs, eating their leaves and flowers. It is quite common in urban areas and in summer-autumn the "tsssk" calls are easily identified. These bright green (sometimes pink when immature) katydids fly well and are active in the daytime, unlike New Zealand weta. An adult with wings that fold along the abdomen (as shown) is about 40mm long, but young start life less than 10mm and lack developed wings.

Conocephalus spp. longhorn grasshoppers or meadow katydids are found in mixed and exotic grassland. Three species have been recorded in New Zealand, but green and brown adults occur within species. Females are equipped with a long straight ovipositor for laying eggs in soil. Adult body is about 15mm long with wings folded horizontally ontop of the abdomen and usually brown. Brachypterous and even wingless individuals also occur.