lesser bilby

A description of the species by Oldfield Thomas was published in 1887, using a specimen forwarded to the British Museum "J. Beazley" of Adelaide, collected at an unknown location; the author determined that the source of the specimen was from the Northern Territory or the vicinity of the southern city of Adelaide. Oldfield Thomas recognized an affinity with the "rabbit-bandicoot" Macrotis lagotis, then described by the genus Peragale, but found distinctions in the specimens that described a new species.

Several later descriptions are synonymous with this species, H. H. Finlayson proposed a new subspecies as Thalacomys minor miseliusin 1932, based on specimens collected at the lower Diamantina, at Cooncherie, and acknowledged the description of Peragale minor by Baldwin Spencer in 1897,{{cite journal |last1=Spencer |first1=B. |title=Description of two new species of marsupials from Central Australia |journal=Proceedings of the Royal Society of Victoria |date=1897 |volume=9 |pages=5–11 |url=https://www.biodiversitylibrary.org/part/71080}} also recognised as a synonym.{{cite journal |last1=Finlayson |first1=H.H. |title=Preliminary descriptions of two new Mammals from South Australia [Thalacomys, Pseudomys] |journal=Transactions of the Royal Society of South Australia |date=1932 |volume=56 |pages=168–171 |url=https://www.biodiversitylibrary.org/part/92284}}

The treatment of the genus was again reviewed by Finlayson in 1935.{{cite journal |last1=Finlayson |first1=H.H. |title=On mammals from the Lake Eyre Basin. Part II - The Peramelidae |journal=Transactions of the Royal Society of South Australia |date=1935 |volume=59 |pages=227–236 |url=https://www.biodiversitylibrary.org/part/271358#/summary}}

The names for the species include white-tailed bilby.

File:Lesserbilby.jpg

The lesser bilby was a medium-sized marsupial with a body mass of 300–435 grams, a combined head-body length of 200–270 millimetres and tail from 120 to 170 mm.{{cite web |url=http://www.nt.gov.au/nreta/wildlife/animals/threatened/pdf/mammals/lesser_bilby_ex.pdf |title=Archived copy |access-date=2008-10-22 |url-status=dead |archive-url=https://web.archive.org/web/20081204185105/http://www.nt.gov.au/nreta/wildlife/animals/threatened/pdf/mammals/lesser_bilby_ex.pdf |archive-date=2008-12-04 }} Its fur colour ranged from pale yellowish-brown to grey-brown with pale white or yellowish-white fur on its belly, with white limbs and tail.{{cite book |author=Francis Harper |year=1945 |title=Extinct and Vanishing Mammals of the Old World |url=https://archive.org/details/extinctvanishing00harprich|publisher=New York, American Committee for International Wild Life Protection }} The tail of this animal was long, about 70% of its total head-body length.

Macrotis have long fur with a silky texture, the species have long tails and mobile ears that resemble those of a common rabbit (lagomorphs); they are burrowing animals that have long and narrow muzzles. The overall coloration of this species was more subdued than the bilby, Macrotis lagotis, and smaller in size; the shorter ears of M. leucura measured 63 mm from base to tip. The underside of the tail had a greyish patch at the base, but the long and bushy fur is otherwise white.{{cite book |last1=Menkhorst |first1=P.W. |last2=Knight |first2=F. |author-link1=Peter Menkhorst |author2-link=Frank Knight |title=A field guide to the mammals of Australia |date=2011 |publisher=Oxford University Press |location=Melbourne |isbn=9780195573954 |page= 84 |edition=3rd}}

An illustration reconstructing the animal in its native setting was painted by Peter Schouten.

Very little is known about its former range and distribution, as the species was collected only six times in modern history, with the first of these coming from an unknown region.{{cite book|title=The IUCN Mammal Red Data Book|url=https://archive.org/details/iucnmammalreddat00thor|url-access=registration| year=1982|publisher=IUCN|isbn=978-2-88032-600-5|page=[https://archive.org/details/iucnmammalreddat00thor/page/33 33]}}

In modern times this species was endemic to the Gibson and Great Sandy deserts of arid central Australia and northeast South Australia and adjoining southeast Northern Territory in the northern half of the Lake Eyre Basin.

It preferred to live in sandy and loamy deserts, spinifex sandplains and dunes, dominated by mounds of tough and grassy Triodia species with mulga Acacia aneura, zygochloa canegrass, or in Triodia hummock grassland with occasional low trees and shrubs.

The lesser bilby, like its surviving relatives, was a strictly nocturnal animal.

It was an omnivore feeding on ants, termites, roots, seeds,{{cite book |author=Hedley Herbert Finlayson |year=1935 |title= On mammals from the Lake Eyre Basin. Part 2. The Peramelidae }} but it also hunted and fed on introduced rodents.

It burrowed in dunes, constructing burrows {{convert|2|to(-)|3|m|ft|0|spell=in}} deep and closing the entrance with loose sand by day.

It is suggested that it may have bred non-seasonally{{Cite web|url=http://www.rainforestinfo.org.au/spp/Schouten/lesser_bilby.htm|title=Lesser Bilby|website=www.rainforestinfo.org.au}} and that giving birth to twins was normal for this species.

Unlike its living relative the greater bilby, the lesser bilby was described as aggressive and tenacious. Hedley Finlayson wrote that this animal was "fierce and intractable, and repulsed the most tactful attempts to handle them by repeated savage snapping bites and harsh hissing sounds".

A collector in the northern territory reported the name used by his Aboriginal informants, Urpila, that distinguished this species from M. lagotis (Urgata), and noted their particular habits. This species would not reside in the deep and narrow part of its burrow in cooler seasons, remaining a short distance from the entrance; this habit was exploited by hunters who would collapse the tunnel behind their prey to force it toward the soft sand covering the opening of the burrow.

Image:Gibson Desert and moon from Alfred & Marie Range.jpg-covered landscape of the Gibson Desert was the native habitat of the lesser bilby.]]

Since its discovery in 1887, the species was rarely seen or collected and remained relatively unknown to science. In 1931, Finlayson encountered many of them near Cooncherie Station, collecting 12 live specimens.{{cite web |url=http://www.environment.gov.au/biodiversity/abrs/publications/fauna-of-australia/pubs/volume1b/25-ind.pdf |title=Archived copy |access-date=2011-05-14 |url-status=dead |archive-url=https://web.archive.org/web/20110605195006/http://www.environment.gov.au/biodiversity/abrs/publications/fauna-of-australia/pubs/volume1b/25-ind.pdf |archive-date=2011-06-05 }} Although according to Finlayson this animal was abundant in that area, these were the last lesser bilbies to be collected alive.

A single specimen collected to the north of Charlotte Waters was deposited at the museum in Melbourne and examined by Baldwin Spencer in 1897, not recognizing it as this species. The collector of Spencer's animal, Patrick Michael Byrne, obtained the specimens with some difficulty.

The last specimen ever found was a skull picked up below a wedge-tailed eagle's nest in 1967 at Steele Gap in the Simpson Desert, Northern Territory. The bones were estimated as being under 15 years old.{{cite book |author=Tim Flannery |author2=Peter Schouten |name-list-style=amp |year=2001 |title=A gap in nature |publisher=Atlantic Monthly Press |isbn=9780871137975 |url=https://archive.org/details/gapinnature00timf |url-access=registration }}

Indigenous Australian oral tradition suggests that this species possibly survived into the 1960s.

The decline in numbers of the lesser bilby and ultimately its extinction was attributed to several different factors. The introductions of foreign predators like the domestic cat and fox, competition with rabbits for food{{Citation needed|date=March 2021}}, changes in the fire regime{{clarify|date=April 2014}} and the degradation of habitat have all been blamed for the extinction of this species. However, Jane Thornback and Martin Jenkins suggest in The IUCN mammal red data book (1982) book that the vegetation in the main part of the animal's range remained intact, with little evidence of cattle or rabbit grazing, and point to cats and foxes as the most likely cause of the extinction of the lesser bilby.

{{Reflist}}

• [http://rainforestinfo.org.au/spp/Schouten/lesser_bilby.htm Lesser bilby]

{{Taxonbar|from=Q531915}}

Category:Peramelemorphs

Category:Extinct marsupials

Category:Extinct mammals of Australia

Category:Extinct mammals of South Australia

Category:Mammals of the Northern Territory

Category:Mammal extinctions since 1500

Category:Marsupials of Australia

Category:Mammals described in 1887

Category:Taxa named by Oldfield Thomas