Weta

Definition

Any of approximately 70–100 species of large, flightless orthopteran insects endemic to New Zealand, belonging primarily to the families Anostostomatidae (giant wetas, tree wetas, tusked wetas, ground wetas) and Rhaphidophoridae (cave wetas). Wetas range from small, slender cave-dwelling species to some of the heaviest insects in the world, with giant wetas (Deinacrida) exceeding 70 g. Most species are nocturnal; smaller forms tend toward carnivory and scavenging, while larger species are principally herbivorous. All wetas lack wings (even as vestigial structures), possess enlarged hind femora armed with spines used for defense and leaping, and have powerful mandibles. Females typically bear a long, sword-like ovipositor for inserting eggs into soil or decaying wood. Many species are saproxylic, dependent on tree hollows or rotting logs, and several are critically endangered due to predation by introduced mammals.

Etymology

From Māori wētā, of uncertain origin; possibly imitative or related to words for 'ugly' or 'god of ugly things' in Māori tradition.

Example

The Cook Strait giant weta (Deinacrida rugosa) and the wetapunga (D. heteracantha) are among the world's heaviest insects, with females of the latter historically reaching masses exceeding 70 grams—heavier than most songbirds.

Synonyms

• wētā

Related Terms

• Orthoptera
• Anostostomatidae
• Rhaphidophoridae
• Deinacrida
• Hemideina
• Endemic
• flightless
• saproxylic
• ovipositor
• katydid
• Grasshopper
• cricket
• introduced predator
• conservation

Usage Notes

The term 'weta' is used both as a common name for the entire assemblage and loosely for individual species; specialists distinguish giant wetas (Deinacrida), tree wetas (Hemideina), ground wetas (Hemiandrus), tusked wetas (Anisoura, Motuweta), and cave wetas (Gymnoplectron, Turbottoplectron, etc.). Cave wetas in Rhaphidophoridae are phylogenetically distant from other weta groups and represent convergent evolution of large size and flightlessness in New Zealand. The spelling 'wētā' with macrons reflects Māori pronunciation and is increasingly preferred in New Zealand English. Not all members of Anostostomatidae are called wetas—related king crickets in Australia and South Africa are distinct. 'Weta' is never applied to the unrelated wetas of Africa (a common name for some tettigoniids), which are true katydids.