Desert rat-kangaroo

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Desert rat-kangaroo
Caloprymnus.jpg
Status iucn3.1 EX.svg
Extinct  (1935)  (IUCN 3.1) [1]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Infraclass: Marsupialia
Order: Diprotodontia
Family: Potoroidae
Subfamily: Potoroinae
Genus: Caloprymnus
Thomas, 1888
Species:
C. campestris
Binomial name
Caloprymnus campestris
(Gould, 1843)
Desert Rat Kangaroo Distribution Map.png
Historic desert rat kangaroo range in orange

The desert rat-kangaroo (Caloprymnus campestris), also called the buff-nosed rat-kangaroo, plains rat-kangaroo or oolacunta, [2] is an extinct small hopping marsupial endemic to desert regions of Central Australia. It was first recorded in the early 1840s and described by John Gould in London in 1843, on the basis of three specimens sent to him by George Grey, the governor of South Australia at the time. [3] [4]

Contents

Description

It was formed like a kangaroo, but had the bulk of a small rabbit, and was described as having a delicate and slender form. [5] The length of the head and body combined is estimated to be about 254–282 mm in addition to a 307 to 377 mm long tail. Its head was short, blunt, and wide, different from that of any kangaroo or wallaby [4] with a naked nose, short and rounded ears. [5]

The color of its dense, straight, soft fur was appropriate for its desert surroundings. It was very pale yellowish brown, the hairs tipped with sooty brown; interspersed with the under fur were many long brownish white hairs. Its underbelly was described as white with very pale yellowish-brown feet and tail. [6]

A distinguishing feature of this species was the difference in size between the fore and hind limbs. Its fore limbs were quite delicate with bones weighing 1 gram, while its hind limbs are large with bones weighing 12 grams. This difference is related to saltation. [7] Other characteristics related to hopping locomotion include a long, but rather thin tail.

Distribution and habitat

Caloprymnus campestris was thought to occupy a relatively small area in South Australia, extending just over the borders of southwestern Queensland and Northern Territory. [8] It was last seen in 1935 in the eastern Lake Eyre basin of northern Southern Australia

The desert rat-kangaroo lived in the desert regions of Australia, including clay pans, loamy flats, sand ridges, and gibber plain habitats. Its native habitat was very arid; cover is sparse, and consists of saltbush and other chenopods and emu bush.

Ecology and behaviour

Caloprymnus campestris was solitary except for mothers with young offspring. It lived in nests built over shallow depressions in the ground. These nests were excavated or found and are crucial in the desert, where temperatures can be high, while relatively little brush or foliage is available for cover. The "pits" were lined with grass, which females carried to the nest with their tails. The nest would then be covered with twigs to provide cover from the scorching sun. Often, the desert rat kangaroo was found peeking out of the top of the nest to observe its surroundings. This species would spend most of the day taking cover in the nest, and emerge at dusk to feed. [7] Thus, it was at least partially nocturnal.

Diet

The desert rat-kangaroo was mainly herbivorous, feeding on foliage and stems of desert vegetation, but has also been found to eat insects such as beetles and weevils. It was so independent of water, it even shunned the succulent plants of the sand hills. It was able to survive without any surface water while feeding on green plants.

Locomotion

It had a distinct method of hopping. Its posture was forward and the long tail was extended when it moved at high speeds. Unlike other marsupials, Caloprymnus would land with the right foot in front of the left foot. It showed great endurance while being chased on horseback at high speeds (Finlayson reported chasing an individual over 12 miles), and "paused only to die". [9]

Reproduction

Females reached sexual maturity at about 11 months, while males reached maturity some two months later. Marked sexual dimorphism was apparent, with females being larger. Females went through estrus at three-week intervals and could mate throughout the year. Although able to mate all year, they had an irregular breeding season when most mating took place. Females with pouched joeys had been found between June and December. Young were born very undeveloped, as is typical of marsupials. Gestation was probably around one to two months, with a pouch period of two to three months. All females were found with only one young at a time. Young remained dependent for over a month after leaving the pouch and soon after would leave permanently. [7]

Rediscovery and extinction

The desert rat-kangaroo was first recorded in the early 1840s. However, after these early sightings, it was no longer recorded for 90 years (aside from an unconfirmed report in 1878), and was widely believed to be extinct. [4] This species, even before European colonisation, was apparently never abundant. [1] Following the relief of drought conditions which improved the local habitat, the animal was rediscovered in 1931 when Hedley Finlayson found a thriving colony of them. [3] [4] He made multiple returns, but after a few years, the population disappeared. The last confirmed record of the species came in 1935 from near Ooroowilanie, east of Lake Eyre. [8]

Caloprymnus campestris was well-adapted to the extremely barren and arid regions it inhabited; these traits saved it from competition by introduced species like the European rabbit or domestic sheep. However, as early as the 1930s, the red fox had spread to the areas inhabited by the desert rat kangaroo. Thus, the rapid decline of the desert rat-kangaroo began shortly after its recovery in 1931 correlates with the invasion of its habitat by the red fox. [10] Predation by the red fox and feral cats, [1] as well as variable seasonal patterns and overhunting by indigenous Australians, [6] were blamed for the extinction of this species.

No reliable reports of the species have been made since 1935, but unconfirmed sightings in Queensland followed periods of rain in 1956-1957 and 1974-1975. [1] Also, recent remains of this species have been found in the mid-1980s inside caves. [7]

The desert rat-kangaroo was declared extinct in 1994, [1] making it the only mammal species to be rediscovered and then lost again. [10]

Possible survival

In view of its amazing recovery following a 90-year period when it was not seen, the extinction of the desert rat-kangaroo is not certain; thus, sightings of this animal would not fall into the cryptozoology category. In similar cases, the broad-faced potoroo was last seen in the late 19th century and is considered extinct, Gilbert's potoroo was considered extinct for 120 years prior to its rediscovery in 1994, and the long-footed potoroo was only discovered in 1967.

The finding of recent remains in the 1980s casts some doubt on the extinction of this species. Professor Ronald Nowak stated in his 2005 book, "perhaps a small population still survives, awaiting the time when it again may increase in response to proper conditions." [11]

2011 Peake Station sighting

An animal was sighted in May 2011 off Peake Station and subsequently identified from a museum skin as a desert rat-kangaroo. The area was then surveyed in August the same year. An old nest with some small macropod like scats was found and some tracks were also found near a waterhole that might have been made by the desert rat-kangaroo. However DNA analysis of the scats failed to yield any usable DNA. No DNA was found in dingo and cat scats in the area as well. As such the sighting remains unconfirmed, but researchers Tony Robinson and Tiana Forrest confirmed the possibility "that a small population of Caloprymnus, generally considered to be extinct throughout its former range across the Lake Eyre Basin, may have been present in this area in May 2011". [2]

Related Research Articles

<span class="mw-page-title-main">Marsupial</span> Infraclass of mammals in the clade Metatheria

Marsupials are a diverse group of mammals belonging to the infraclass Marsupialia. They are primarily found in Australasia, Wallacea, and the Americas. One of the defining features of marsupials is their unique reproductive strategy, where the young are born in a relatively undeveloped state and then nurtured within a pouch.

<span class="mw-page-title-main">Diprotodontia</span> Order of marsupial mammals

Diprotodontia is the largest extant order of marsupials, with about 155 species, including the kangaroos, wallabies, possums, koala, wombats, and many others. Extinct diprotodonts include the hippopotamus-sized Diprotodon, and Thylacoleo, the so-called "marsupial lion".

<span class="mw-page-title-main">Broad-faced potoroo</span> Extinct species of marsupial

The broad-faced potoroo is an extinct potoroid marsupial that was found in southwestern Australia. The first specimen was collected in 1839, and described by John Gould in 1844. Only a small number of specimens have been collected since. The last live capture was in 1875. Subfossil remains indicate that it had an extensive distribution around the semiarid coastal districts of Southwest Australia.

<span class="mw-page-title-main">Potoroidae</span> Family of marsupials

Potoroidae is a family of marsupials, small Australian animals known as bettongs, potoroos, and rat-kangaroos. All are rabbit-sized, brown, jumping marsupials and resemble a large rodent or a very small wallaby.

<span class="mw-page-title-main">Bridled nail-tail wallaby</span> Species of marsupial

The bridled nail-tail wallaby, also known as the bridled nail-tailed wallaby, bridled nailtail wallaby, bridled wallaby, merrin, and flashjack, is a vulnerable species of macropod. It is a small wallaby found in three isolated areas in Queensland, Australia, and whose population is declining. In early 2019 the total population of the species was estimated to be fewer than 500 mature individuals in the wild and 2285 in captivity.

<span class="mw-page-title-main">Woylie</span> Species of marsupial

The woylie or brush-tailed bettong is a small, critically endangered mammal native to forests and shrubland of Australia. A member of the rat-kangaroo family (Potoroidae), it moves by hopping and is active at night, digging for fungi to eat. It is also a marsupial and carries its young in a pouch. Once widespread, the woylie mostly died out from habitat loss and introduced predators such as foxes. It is currently restricted to two small areas in Western Australia. There were two subspecies: B. p. ogilbyi in the west, and the now-extinct B. p. penicillata in the southeast.

<i>Chaeropus</i> Extinct genus of marsupials

Chaeropus, known as the pig-footed bandicoots, is a genus of small marsupials that became extinct during the 20th century. They were the only members of the family Chaeropodidae in order Peramelemorphia, with unusually thin legs, yet were able to move rapidly. Two recognised species inhabited dense vegetation on the arid and semiarid plains of Australia. The genus' distribution range was later reduced to an inland desert region, where it was last recorded in the 1950s; it is now presumed extinct.

<span class="mw-page-title-main">Eastern bettong</span> Species of marsupial

The eastern bettong, also known as the southern or Tasmanian bettong, is a small, hopping, rat-like mammal native to grassy forests of southeastern Australia and Tasmania. A member of the rat-kangaroo family (Potoroidae), it is active at night and feeds on fungi and plant roots. Like most marsupials, it carries its young in a pouch. The eastern bettong is under pressure by introduced predators and habitat loss. The subspecies on mainland Australia is extinct, but populations of the Tasmanian subspecies have been reintroduced there.

<span class="mw-page-title-main">Musky rat-kangaroo</span> Species of marsupial

The musky rat-kangaroo is a small marsupial found only in the rainforests of northeastern Australia. First described in the later 19th century, the only other species are known from fossil specimens. They are similar in appearance to potoroos and bettongs, but are not as closely related. Their omnivorous diet is known to include materials such as fruit and fungi, as well as small animals such as insects and other invertebrates.

<span class="mw-page-title-main">Long-nosed potoroo</span> Species of marsupial

The long-nosed potoroo is a small, hopping mammal native to forests and shrubland of southeastern Australia and Tasmania. A member of the potoroo and bettong family (Potoroidae), it lives alone and digs at night for fungi, roots, or small insects. It is also a marsupial and carries its young in a pouch. The long-nosed potoroo is threatened by habitat loss and introduced species such as cats or foxes. There are two subspecies: P. t. tridactylus on mainland Australia, and P. t. apicalis on Tasmania, with lighter fur.

<span class="mw-page-title-main">Fat-tailed dunnart</span> Species of mammal

The fat-tailed dunnart is a species of mouse-like marsupial of the Dasyuridae, the family that includes the little red kaluta, quolls, and the Tasmanian devil.

<span class="mw-page-title-main">Gilbert's potoroo</span> Species of marsupial

Gilbert's potoroo or ngilkat is Australia's most endangered marsupial, the rarest marsupial in the world, and one of the world's rarest critically endangered mammals, found in south-western Western Australia. It is a small nocturnal macropod that lives in small groups.

<span class="mw-page-title-main">Potoroo</span> Genus of marsupials

Potoroo is a common name for species of Potorous, a genus of smaller marsupials. They are allied to the Macropodiformes, the suborder of kangaroo, wallaby, and other rat-kangaroo genera. All three extant species are threatened by ecological changes since the colonisation of Australia, especially the long-footed potoroo Potorous longipes (endangered) and P. gilbertii. The broad-faced potoroo P. platyops disappeared after its first description in the 19th century. The main threats are predation by introduced species and habitat loss.

<span class="mw-page-title-main">Macropodiformes</span> Suborder of marsupials

The Macropodiformes, also known as macropods, are one of the three suborders of the large marsupial order Diprotodontia. They may in fact be nested within one of the suborders, Phalangeriformes. Kangaroos, wallabies and allies, bettongs, potoroos and rat kangaroos are all members of this suborder.

<span class="mw-page-title-main">Boodie</span> Species of marsupial

The boodie, also known as the burrowing bettong or Lesueur's rat-kangaroo, is a small, furry, rat-like mammal native to Australia. Once common throughout the continent, it is now restricted to a few coastal islands. A member of the rat-kangaroo family (Potoroidae), it lives in burrows and is active at night when it forages for fungi, roots, and other plant matter. It is about the size of a rabbit and, like most marsupials, carries its young in a pouch.

The long-footed potoroo is a small marsupial found in southeastern Australia, restricted to an area around the coastal border between New South Wales and Victoria. It was first recorded in 1967 when an adult male was caught in a dog trap in the forest southwest of Bonang, Victoria. It is classified as vulnerable.

<span class="mw-page-title-main">Rufous rat-kangaroo</span> Species of marsupial

The rufous rat-kangaroo or rufous bettong is a small, jumping, rat-like marsupial native to eastern Australia. It is the only species in the genus Aepyprymnus. The largest member of the potoroo/bettong family (Potoroidae), it is about the size of a rabbit. The rufous rat-kangaroo is active at night when it digs for plant roots and fungi, and like other marsupials it carries its young in a pouch. Though its range is reduced, the population is healthy and stable.

<span class="mw-page-title-main">Bettong</span> Genus of marsupials

Bettongs, species of the genus Bettongia, are potoroine marsupials once common in Australia. They are important ecosystem engineers displaced during the colonisation of the continent, and are vulnerable to threatening factors such as altered fire regimes, land clearing, pastoralism and introduced predatory species such as the fox and cat.

References

  1. 1 2 3 4 5 Woinarski, J.; Burbidge, A.A. (2016). "Caloprymnus campestris". IUCN Red List of Threatened Species . 2016: e.T3626A21961545. doi: 10.2305/IUCN.UK.2016-2.RLTS.T3626A21961545.en . Retrieved 19 November 2021.
  2. 1 2 Tony Robinson & Tiana Forrest (2012) A possible sighting of the Desert Rat-kangaroo or Oolacunta (Caloprymnus campestris) on the Peake Station, South Australia The South Australian Naturalist, 86(2) Jul-Dec 2012. Retrieved 8 May 2016.
  3. 1 2 Johnson, C. (2006). "Chapter 1: A brief history of Australia's mammals" (PDF). Australia's mammal extinctions: a 50,000 year history. Cambridge University Press. p. 278. ISBN   978-0-521-84918-0. OCLC   63187432.
  4. 1 2 3 4 Finlayson, H. H. (1932-06-11). "Rediscovery of Caloprymnus campestris (Marsupialia)". Nature . 129 (3267): 871. Bibcode:1932Natur.129..871F. doi: 10.1038/129871b0 . S2CID   4075003.
  5. 1 2 Richard Lydekker (1894). A hand-book to the marsupialia and monotremata (PDF).
  6. 1 2 Francis Harper (1945). Extinct and Vanishing Mammals of the Old World. New York, American Committee for International Wild Life Protection.
  7. 1 2 3 4 "Caloprymnus campestris (Desert rat kangaroo)".
  8. 1 2 "Caloprymnus campestris — Desert Rat-kangaroo". Australian Department of Sustainability, Environment, Water, Population and Communities . Retrieved 2011-09-03.
  9. Heddle, Enid Moodie; Millington, Iris (1962), How Australian literature grew, F. W. Cheshire, retrieved 1 August 2009
  10. 1 2 Fisher, D. O.; Blomberg, S. P. (2010-09-29). "Correlates of rediscovery and the detectability of extinction in mammals". Proceedings of the Royal Society B . 278 (1708): 1090–1097. doi:10.1098/rspb.2010.1579. PMC   3049027 . PMID   20880890.
  11. Ronald Nowak (2005). Walker's Marsupials of the World. ISBN   978-0-8018-8222-7.