Wētā (also spelled weta in English) is the common name for a group of about 100 insect species in the families Anostostomatidae and Rhaphidophoridae endemic to New Zealand.

Their physical appearance is like a katydid, long-horned grasshopper, or cricket, but the hind legs are enlarged and usually very spiny.

Because they can cope with variations in temperature, wētā are found in a variety of environments, including alpine, forests, grasslands, caves, shrub lands and urban gardens.

Tree wētā lift their hind legs in a defence displays to look large and spiky, but they tend to retreat if given the chance.

Tree wētā raise their hind legs into the air in warning to foes, and then bring them down to stridulate.

The female wētā looks as if she has a stinger, but it is an ovipositor, which enables her to lay eggs inside rotting or mossy wood or soil.

[17] Fossilised orthopterans have been found in Russia, China, South Africa, Australia, and New Zealand, but the relationships are open to different interpretations by scientists.

[19] [20] The present species might have resulted from a recent radiation, which conflicts with those earlier ideas about dispersal of wētā forebears around the Southern Hemisphere (Wallis et al. 2000).

Giant, tree, ground, and tusked wētā are all members of the family Anostostomatidae (formerly in the Stenopelmatidae, but recently separated).

They are heavy herbivorous Orthoptera with a body length of up to 100 mm (3.9 in), excluding their long legs and antennae, and weigh about 20–30 g. A captive giant wētā (Deinacrida heteracantha) filled with eggs reached a record 70 g,[26] making it one of the heaviest documented insects in the world[27] and heavier than a sparrow.

Tree wētā (Hemideina) are commonly encountered in suburban settings in New Zealand's North Island.

They are up to 40 mm long and most commonly live in holes in trees formed by beetle and moth larvae[28] or where rot has set in after a twig has broken off.

The hole, called a gallery, is maintained by the wētā and any growth of the bark surrounding the opening is chewed away.

They readily occupy a preformed gallery in a piece of wood (a "wētā motel") and can be kept in a suburban garden as pets.

It is a ground-dwelling wētā, entombing itself in shallow burrows during the day, and is critically endangered: a Department of Conservation breeding programme has established new colonies on other islands in the Mercury group.

Although they have no hearing organs on their front legs like species of Hemideina and Deinacrida, some (such as Talitropsis) are very sensitive to ground vibrations sensed through pads on their feet.

[43] New Zealanders Peter Jackson, Richard Taylor, and Jamie Selkirk founded visual effects company Weta Digital (now known as Wētā FX), naming it after the insect.

[44] One of Jackson's films, King Kong, has among the Skull Island fauna oversized versions of the giant wētās, referred to with the scientific name "Deinacrida rex" or "Wētā-rex".