Katydids

Definition

Common name for insects of the family Tettigoniidae, a diverse group of orthopterans characterized by extremely long, thread-like antennae (often longer than the body), enlarged hind legs adapted for jumping, and typically nocturnal habits. Katydids produce sound by stridulation—rubbing specialized forewing structures together—and are distinguished from grasshoppers (family Acrididae) by their antennae length and taxonomic placement in the suborder Ensifera rather than Caelifera.

Etymology

From the onomatopoeic rendering of the repetitive 'katy-did, katy-didn't' call of North American species, particularly Pterophylla camellifolia.

Example

The greater angle-wing katydid (Microcentrum rhombifolium) mimics green leaves so precisely that its wing venation resembles leaf midribs and margins, providing camouflage against avian predators during daytime roosting.

Synonyms

• bush crickets
• long-horned grasshoppers

Related Terms

• Tettigoniidae
• Ensifera
• stridulation
• orthopterans
• grasshoppers
• Acrididae
• Caelifera
• tegmina
• ovipositor

Usage Notes

The term 'long-horned grasshoppers' is now largely abandoned because katydids are not true grasshoppers; the two groups represent parallel radiations within Orthoptera. In British English, 'bush crickets' predominates. The common name 'katydid' applies most strictly to North American fauna but is widely used internationally for the family. Distinguishing katydids from crickets (family Gryllidae, also Ensifera) requires examination of ovipositor shape, tarsal segmentation, and stridulatory file structure.