Snipe-rail
Encyclopedia
The Snipe-rail is an extinct flightless rail
endemic to the North Island
of New Zealand
. The species' name is derived from the Karamu Cave 21 kilometres (13 mi) from Hamilton
where the holotype
was discovered in 1954.
which had a bill of about 7 centimetre, very long in proportion to its body size. Its weight was about 240 grams. The type material consists of an incomplete skeleton
, including vertebrae, a pelvis
, and a hind limb
. Since the discovery of these remains, many complete skeletons consisting of hundreds of bones have been unearthed on different sites in the North Island. The Snipe-rail has a specific position among New Zealand rail species. Its evolutionary relationships to other rail species are unclear but the structure of its bones suggests that it might have been a relative of the likewise extinct Chatham Rail
. As measured by its body size the Snipe-rail had the smallest wings of all known rail species. It also had a disproportionally large tarsometatarsus
.
s prevailed. The bird's long bill suggests that it was able to forage by probing in a similar manner to kiwi
.
became widespread in New Zealand.
Rallidae
The rails, or Rallidae, are a large cosmopolitan family of small to medium-sized birds. The family exhibits considerable diversity and the family also includes the crakes, coots, and gallinules...
endemic to the North Island
North Island
The North Island is one of the two main islands of New Zealand, separated from the much less populous South Island by Cook Strait. The island is in area, making it the world's 14th-largest island...
of New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
. The species' name is derived from the Karamu Cave 21 kilometres (13 mi) from Hamilton
Hamilton, New Zealand
Hamilton is the centre of New Zealand's fourth largest urban area, and Hamilton City is the country's fourth largest territorial authority. Hamilton is in the Waikato Region of the North Island, approximately south of Auckland...
where the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
was discovered in 1954.
Description
The Snipe-rail was a relatively small railRallidae
The rails, or Rallidae, are a large cosmopolitan family of small to medium-sized birds. The family exhibits considerable diversity and the family also includes the crakes, coots, and gallinules...
which had a bill of about 7 centimetre, very long in proportion to its body size. Its weight was about 240 grams. The type material consists of an incomplete skeleton
Skeleton
The skeleton is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.In a figurative sense, skeleton can...
, including vertebrae, a pelvis
Pelvis
In human anatomy, the pelvis is the lower part of the trunk, between the abdomen and the lower limbs .The pelvis includes several structures:...
, and a hind limb
Hind limb
A hind limb is a posterior limb on an animal. When referring to quadrupeds, the term hind leg is often instead used....
. Since the discovery of these remains, many complete skeletons consisting of hundreds of bones have been unearthed on different sites in the North Island. The Snipe-rail has a specific position among New Zealand rail species. Its evolutionary relationships to other rail species are unclear but the structure of its bones suggests that it might have been a relative of the likewise extinct Chatham Rail
Chatham Rail
The Chatham Rail is an extinct species of bird in the Rallidae family. It was endemic to New Zealand.Cabalus modestus was endemic to Chatham, Mangere and Pitt Islands, New Zealand. It was first discovered on Mangere in 1871, and 26 specimens collected there are known from museum collections. It...
. As measured by its body size the Snipe-rail had the smallest wings of all known rail species. It also had a disproportionally large tarsometatarsus
Tarsometatarsus
The tarsometatarsus is a bone that is found in the lower leg of certain tetrapods, namely birds.It is formed from the fusion of several bones found in other types of animals, and homologous to the mammalian tarsal and metatarsal bones...
.
Habitat and ecology
The bone findings were in the western areas of the North Island where wetter, closed-canopy rainforestRainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
s prevailed. The bird's long bill suggests that it was able to forage by probing in a similar manner to kiwi
Kiwi
Kiwi are flightless birds endemic to New Zealand, in the genus Apteryx and family Apterygidae.At around the size of a domestic chicken, kiwi are by far the smallest living ratites and lay the largest egg in relation to their body size of any species of bird in the world...
.
Extinction
The exact date of the snipe-rail's extinction is unknown, but it is supposed that the decline began in the 13th century when the Polynesian RatPolynesian Rat
The Polynesian Rat, or Pacific Rat , known to the Māori as kiore, is the third most widespread species of rat in the world behind the Brown Rat and Black Rat. The Polynesian Rat originates in Southeast Asia but, like its cousins, has become well travelled – infiltrating Fiji and most Polynesian...
became widespread in New Zealand.
Further reading
- Worthy, Trevor H. & Holdaway, Richard N. : The Lost World of the Moa. Prehistoric Life of New Zealand. Indiana University Press, Bloomington 2002. ISBN 0253340349
- Scarlett, Ron (1970): The genus Capellirallus In: Notornis (1970) :pp. 303–319. Quarterly Journal of the Ornithological Society of New Zealand.
