Orthoptera

Definition

An order of polyneopteran insects comprising grasshoppers, locusts, crickets, katydids, and wetas, distinguished by saltatorial (jumping) hind legs, leathery forewings (tegmina), and often well-developed acoustic communication via stridulation. The order is divided into two suborders: Caelifera (short-horned grasshoppers and locusts, with antennae shorter than the body and tympanal organs on the first abdominal segment) and Ensifera (crickets, katydids, and wetas, with long filamentous antennae and tympanal organs on the fore tibiae). Adults and nymphs are primarily herbivorous, though some species are omnivorous or predatory. Many species exhibit density-dependent phase polymorphism, with solitary and gregarious forms that differ in morphology, behavior, and physiology.

Etymology

From Greek orthos (straight) + pteron (wing), referring to the roof-like folding of the tegmina over the abdomen.

Example

The field grasshopper Chorthippus brunneus (family Acrididae, suborder Caelifera) is one of the most common orthopterans in the UK, identified by its buzzing song produced by rubbing the hind femora against the forewings.

Related Terms

• Caelifera
• Ensifera
• saltatorial
• stridulation
• tegmina
• Tympanum
• phase polymorphism
• Acrididae
• Tettigoniidae
• Gryllidae

Usage Notes

Orthoptera formerly included cockroaches (Blattodea), stick insects (Phasmatodea), mantids (Mantodea), and earwigs (Dermaptera), which are now placed in separate orders. The term 'orthopteran' (singular noun or adjective) refers to any member of this order. Orthopterists specialize in their study and often identify species by their distinctive calling songs. Not all orthopterans jump—some wetas and certain crickets are flightless and slow-moving—but the saltatorial leg morphology remains a defining synapomorphy of the order.