刺鹩科科

• 刺鹩属（Acanthisitta）
• 刺鹩（Acanthisitta chloris）
• 异鹩属（Xenicus）
• †丛异鹩（Xenicus longipes）
• 石异鹩（Xenicus gilviventris）
• †斯蒂芬岛异鹩（Xenicus lyalli）
• 粗腿鹩属（Pachyplichas）
• †南岛粗腿鹩（Pachyplichas yaldwyni）
• †北岛粗腿鹩（Pachyplichas jagmi）
• 长嘴鹩属（Dendroscansor）
• †长嘴鹩（Dendroscansor decurvirostris）

The New Zealand wrens are a family (Acanthisittidae) of tiny passerines endemic to New Zealand. They were represented by seven Holocene species in four or five genera, although only two species in two genera survive today. They are understood to form a distinct lineage within the passerines, but authorities differ on their assignment to the oscines or suboscines (the two suborders that between them make up the Passeriformes). More recent studies suggest that they form a third, most ancient, suborder Acanthisitti and have no living close relatives at all. They are called "wrens" because of similarities in appearance and behaviour to the true wrens (Troglodytidae) but are not members of that family.

New Zealand wrens are mostly insectivorous foragers of New Zealand's forests, with one species, the New Zealand rock wren, being restricted to alpine areas. Both the remaining species are poor fliers and four of the five extinct species are known or suspected to have been flightless. Along with the long-legged bunting from Tenerife, one of the Canary Islands, they are the only passerines known to have lost the ability to fly. Of the species for which the plumage is known, they are drab-coloured birds with brown-green plumage. They form monogamous pair bonds to raise their young, laying their eggs in small nests in trees or amongst rocks. They are diurnal and like all New Zealand passerines, are, for the most part, sedentary.

Like many New Zealand birds, New Zealand wrens suffered several extinctions after the arrival of humans in New Zealand. Of the seven Holocene species, only two survive today. The South Island stout-legged wren, North Island stout-legged wren, and long-billed wren became extinct after the arrival of the Māori and the Polynesian rat. They are known to science only from

subfossil remains. At the same time, Lyall's wren became extinct on the main islands and survived only as a relict population on Stephens Island in the Cook Strait. Lyall's wren and the bushwren became extinct after the arrival of Europeans in 1895 and 1972 respectively. Of the two remaining species, the rifleman is still common in both the North and South Islands. The New Zealand rock wren is restricted to the alpine areas of the South Island and is considered endangered.

Taxonomy and systematics

The taxonomy of the New Zealand wrens has been a subject of considerable debate since their discovery, although they have long been known to be an unusual family. In the 1880s, Forbes assigned the New Zealand wrens to the suboscines related to the cotingas and the pittas (and gave the family the name Xenicidae). Later, they were thought to be closer to the ovenbirds and antbirds. Sibley's 1970 study comparing egg-white proteins moved them to the oscines, but later studies, including the 1982 DNA-DNA hybridisation study, suggested the family was a sister taxon to the suboscines and the oscines.

Description

New Zealand wrens are tiny birds; the rifleman is the smallest of New Zealand's birds. Their length ranges from 7 to 10 cm and their weight ranges from as little as 5–7 g for the rifleman, to an estimated 50 g for the extinct stout-legged wren. The New Zealand rock wren (and probably the bushwren) weighs between 14 and 22 g and the extinct long-billed wren weighed around 30 g.

The plumage of the New Zealand wrens is only known for the four species seen by European scientists. All these species have dull green and brown plumage and all except Lyall's wren have a prominent supercilium above the eye.

Distribution and habitat

The New Zealand wrens are endemic and restricted to the main and offshore islands of New Zealand; they have not been found on any of the outer islands such as the Chatham Islands or the Kermadec Islands. Prior to the arrival of humans in New Zealand (about 1280 CE), they had a widespread distribution across both the North and South Islands and on Stewart Island. The range of the rifleman and bushwren included southern beech forest and podocarp-broadleaf forest, with the range of the bushwren also including coastal forest and scrub, particularly the Stewart Island subspecies. Currently, the New Zealand rock wren is confined to alpine and subalpine zones (900–2500 m altitude) on the South Island.