Stout-legged wren is a common name referring to two species of extinct

New Zealand wren 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 ...

s: the North Island stout-legged wren or Grant-Mackie's wren (''Xenicus jagmi''), and the South Island stout-legged wren or Yaldwyn's wren (''Xenicus yaldwyni''). These small birds were

endemic Endemism is the state of a species being found only 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 foun ...

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

and were previously included in the genus '' Pachyplichas''.

History and etymology

The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

for the North Island wren is a right

tarsometatarsus The tarsometatarsus is a bone that is only found in the lower leg of birds and some non-avian dinosaurs. It is formed from the fusion of several bird bones found in other types of animals, and homologous to the mammalian tarsus (ankle bones) a ...

(AU 7102.20 in the collections of the

Auckland University The University of Auckland (; Māori language, Māori: ''Waipapa Taumata Rau'') is a public university, public research university based in Auckland, New Zealand. The institution was established in 1883 as a constituent college of the Unive ...

Geology Department) collected on 25 August 1978 from the Ruakuri Cave in the Waitomo District of

North Island The North Island ( , 'the fish of Māui', historically New Ulster) is one of the two main islands of New Zealand, islands of New Zealand, separated from the larger but less populous South Island by Cook Strait. With an area of , it is the List ...

of New Zealand. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

honours Dr John Grant-Mackie, Associate Professor of Geology at Auckland University, in recognition of his support for graduate students and for contributions to avian

palaeontology Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geo ...

. The

for the South Island wren is a right

(NMNZS 22683 in the collections of the National Museum) collected on 29 September 1983 from the Honeycomb Hill Cave. The

honours Dr John Yaldwyn, Director of the National Museum of New Zealand in

Wellington Wellington 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 third-largest city in New Zealand (second largest in the North Island ...

, in recognition of his contributions to avian

Description

North: This wren is similar to, though smaller than, its congener from

South Island The South Island ( , 'the waters of Pounamu, Greenstone') is the largest of the three major islands of New Zealand by surface area, the others being the smaller but more populous North Island and Stewart Island. It is bordered to the north by ...

, the South Island stout-legged wren (''Xenicus yaldwyni''), with which it forms a

species pair In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

. Its reduced wings and robust legs indicate that it was strongly adapted to a terrestrial existence and was either

flightless Flightless birds are birds that cannot fly, as they have, through evolution, lost the ability to. There are over 60 extant species, including the well-known ratites ( ostriches, emus, cassowaries, rheas, and kiwis) and penguins. The smal ...

or nearly so. South: It was the largest (by weight) of the

s. The

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

of the wren indicates that it was strongly adapted to a terrestrial existence. Radiocarbon dates for the assemblages with which it is associated range from 25,000 BP to 1,000 BP. Either

or nearly so, it became

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

following the occupation of New Zealand by the Polynesian ancestors of the

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the Co ...

, and the associated introduction of the '' kiore'' (Pacific rat).

Distribution and habitat

The

subfossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

remains of the wren have only been found in the

of New Zealand, and it seems to have formed a

with the closely related '' P. jagmi'', which was only found in the

. Since it has been found in association with four other

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of acanthisittids in four genera (at the Honeycomb Hill Cave site) it is likely that its

ecological niche In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of Resource (biology), resources an ...

was different enough for it to have coexisted with them. Sites where it was found indicate that it inhabited lowland mixed podocarp

broadleaf forest A forest is an ecosystem characterized by a dense community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological functio ...

, ranging upwards into

alpine tundra Alpine tundra is a type of natural region or biome that does not contain trees because it is at high elevation, with an associated harsh climate. As the latitude of a location approaches the poles, the threshold elevation for alpine tundra gets ...

scrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominance (ecology), dominated by shrubs, often also including grasses, herbaceous plant, herbs, and geophytes. Shrubland may either occur naturally o ...

References

External links

Holotype of Pachyplichas yaldwyni
from the collection of the Museum of New Zealand Te Papa Tongarewa
Stout-legged Wren'', ''Pachyplichas yaldwyni'', by Paul Martinson
Artwork produced for the book ''Extinct Birds of New Zealand'', by Alan Tennyson, Te Papa Press, Wellington, 2006 Extinct birds of New Zealand Xenicus Holocene extinctions Fossil taxa described in 1988 Late Quaternary prehistoric birds Birds described in 1988 {{Paleo-bird-stub