Tree wētā are

wētā Wētā (also spelt weta) is the common name for a group of about 100 insect species in the families Anostostomatidae and Rhaphidophoridae endemic to New Zealand. They are giant flightless crickets, and some are among the heaviest insects in th ...

in the genus ''Hemideina'' of the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Anostostomatidae Anostostomatidae is a family of insects in the order Orthoptera, widely distributed in the southern hemisphere. It is named Mimnermidae or Henicidae in some taxonomies, and common names include ''king crickets'' in South Africa and ''wētā'' in ...

. The genus is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 List of islands of New Zealand, smaller islands. It is the ...

. There are seven species within the genus ''Hemideina'', found throughout the country except lowland

Otago Otago (, ; mi, Ōtākou ) is a region of New Zealand located in the southern half of the South Island administered by the Otago Regional Council. It has an area of approximately , making it the country's second largest local government reg ...

and Southland. Because many tree wētā species are common and widespread they have been used extensively in studies of ecology and evolution.

Habitat

Tree wētā are commonly encountered in forests and suburban gardens throughout most of New Zealand. They are up to 40 mm long and most commonly live in holes in trees formed by beetle and moth larvae 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. A gallery might house a harem of up to 10 adult females and one male.

Behaviour

Tree wētā are

nocturnal Nocturnality is an ethology, animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatures generally have ...

and

arboreal Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. The habitats pose num ...

, hiding in hollow tree branches during the day and feeding at night. Their diet consists of leaves, flowers, fruit and small insects. Males have larger heads and stronger jaws than females, though both sexes will

stridulate Stridulation is the act of producing sound by rubbing together certain body parts. This behavior is mostly associated with insects, but other animals are known to do this as well, such as a number of species of fish, snakes and spiders. The mech ...

and bite when threatened. Hemideina_crassidens_harem

MA I066498 TePapa Hemideina-broughi-Buller1896 full

Species

The seven species of tree wētā are: ; Auckland tree wētā, '' Hemideina thoracica'' (White, 1846) : Also known as tokoriro; found throughout the

North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-larges ...

apart from the

Wellington Wellington ( mi, Te Whanganui-a-Tara or ) is the capital city of New Zealand. It is located at the south-western tip of the North Island, between Cook Strait and the Remutaka Range. Wellington is the second-largest city in New Zealand by m ...

Wairarapa The Wairarapa (; ), a geographical region of New Zealand, lies in the south-eastern corner of the North Island, east of metropolitan Wellington and south-west of the Hawke's Bay Region. It is lightly populated, having several rural service t ...

region. Within this range are nine chromosome races and there are five hybrid zones where six of these races meet. ; Hawke's Bay tree wētā, '' Hemideina trewicki'' Morgan-Richards, 1995 :

Hawke's Bay Hawke's Bay ( mi, Te Matau-a-Māui) is a local government region on the east coast of New Zealand's North Island. The region's name derives from Hawke Bay, which was named by Captain James Cook in honour of Admiral Edward Hawke. The region ...

. ; Wellington tree wētā, ''

Hemideina crassidens ''Hemideina crassidens'', commonly known as the Wellington tree wētā, is a large, flightless, nocturnal insect in the family Anostostomatidae. This wētā species is endemic to New Zealand and populates regions in the southern half of North Isla ...

'' (Blanchard, 1851) :

, the

, the northern part of the

South Island The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasma ...

, and the West Coast. They have been the subject of studies of coevolution, sexual selection, hybridisation and range shifts. ; Canterbury tree wētā, '' Hemideina femorata'' Hutton, 1898 : Marlborough and

Canterbury Canterbury (, ) is a cathedral city and UNESCO World Heritage Site, situated in the heart of the City of Canterbury local government district of Kent, England. It lies on the River Stour. The Archbishop of Canterbury is the primate of ...

. ; Mountain stone wētā, ''

Hemideina maori ''Hemideina maori'', also known as the mountain stone wētā, is a wētā of the family Anostostomatidae. They are a large, flightless, nocturnal orthopteran endemic to New Zealand. Mountain stone wētā are long lived and are found on many ce ...

'' (Pictet & Saussure, 1891) : The drier areas of the central

South Island high country High country is a New Zealand term for the elevated pastoral land of the South Island and – to a lesser extent – North Island. This terrain, which can be compared loosely with the outback of Australia, high veldt of South Africa and pampas of ...

, living above the treeline. This species abandoned life in the forest millions of years ago in favour of crevices and cavities under rocks. ; Banks Peninsula tree wētā, '' Hemideina ricta'' Hutton, 1898 : A rare species only found on

Banks Peninsula Banks Peninsula is a peninsula of volcanic origin on the east coast of the South Island of New Zealand. It has an area of approximately and encompasses two large harbours and many smaller bays and coves. The South Island's largest city, ...

. ;West Coast bush wētā, '' Hemideina broughi'' (Buller, 1896) : Overlaps with the Wellington tree wētā in Nelson and the northern West Coast. The three North Island tree wētā species are closely related but each has a distinctive set of chromosomes (

karyotype A karyotype is the general appearance of the complete set of metaphase chromosomes in the cells of a species or in an individual organism, mainly including their sizes, numbers, and shapes. Karyotyping is the process by which a karyotype is disce ...

). When the territories of species overlap, as with the related species ''H. femorata'' and ''H. ricta'' on Banks Peninsula, they may interbreed, although offspring are sterile.

References

{{Taxonbar, from=Q10521122 Weta Anostostomatidae