User:Ankylosaur Enthusiast/sandbox4

Ankylosaur Enthusiast/sandbox4 Temporal range: Late Oligocene,
Holotype of B. turnbulli
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Infraclass:	Marsupialia
Order:	Dasyuromorphia
Family:	†Thylacinidae
Genus:	†Badjcinus Muirhead & Wroe, 1998
Type species
†Badjcinus turnbulli Muirhead & Wroe, 1998
Other species
†B. timfaulkneri Churchill, Archer & Hand, 2024

Badjcinus

History and naming

The description of the type species, B. turnbulli, was published in 1998, emerging from an examination undertaken by Jeanette Muirhead and Stephen Wroe on specimens obtained at the Riversleigh World Heritage Area in northwestern Queensland, Australia. The holotype of B. turnbulli (QM F30408) is a partial skull consisting of the premaxilla, maxilla, nasals, frontals, zygomatic arches, parietals and basicranium. The authors also referred three partial dentaries and an isolated molar to the species. All specimens are a part of the paleontological collection at the Queensland Museum.

In 2024, a new, slightly older species of Badjcinus, B. timfaulkneri, was named based on a nearly complete dentary and an isolated molar. Both fossils are thought to have belonged to adult individuals. It also stems from Riversleigh deposits.

The generic name derives from the Waanyi word "badj" (expert hunter) and the Ancient Greek stem word "-kynos" (dog), from which the Thylacinidae name was originally derived.

Species

• Badjcinus turnbulli

The type species, B. turnbulli was named in 1998 based on fossils discovered at the White Hunter site of the Riversleigh World Heritage Area in Queensland, dating to the late Oligocene. It was named after William D. Turnbull, for their contributions to Australian vertebrate palaeontology.

• Badjcinus timfaulkneri

B. timfaulkneri is the larger and oldest of the two species, known from the Hiatus site of Riversleigh, making it the oldest named thylacinid. It differs from the type species in aspects of the dentition. The species name was chosen to honour Tim Faulkner, for their dedication to the conservation of Australian wildlife and dasyuromorphians in particular.

Description

Size

B. timfaulkneri was a surprisingly large thylacinid for its time, weighing up to 6.7-11.4 kg (14.8-25.1 lbs). In contrast, B. turnbulli was a lot smaller, with an estimated weight of 1.7-3.1 kg (3.7-6.8 lbs).

Classification

In its original description, Badjcinus was considered to be the basalmost/most plesiomorphic thylacinid. Wroe (2003) recovered it in a polytomy and as sister taxon to a clade of derived thylacinids. Both Murray & Megirian (2000) and Yates (2014/2015) recovered it as sister taxon to Ngamalacinus. Archer et al. (2016) also recovered it as the basalmost/most plesiomorphic thylacinid. Three analyses were conducted by Rovinsky et al. (2019), two of them recovered it as the basalmost thylacinid, whereas the remaining analysis found it to be in a basal polytomy containing taxa like Nimbacinus, Muribacinus and Ngamalacinus,

Churchill et al. (2024) also produced three analyses. Two of which recovered the newly named B. timfaulkneri within a polytomy and separate from each other. Only one analysis recovered both species as sister taxa

	Thylacinidae Badjcinus turnbulli Nimbacinus dicksoni Muribacinus gadiyuli Ngamalacinus timmulvaneyi Tyarrpecinus rothi Wabulacinus ridei Thylacinus Thylacinus macknessi Thylacinus potens Thylacinus megiriani Thylacinus yorkellus Thylacinus cynocephalus

Paleobiology

Species of Badjcinus may have preferred to live in open forests or woodlands.

B. turnbulli is known only from the Late Oligocene White Hunter site of Riversleigh, which has an estimated age of ~26-23 Ma. On the other hand, specimens of B. timfaulkneri have been recovered at the slightly older Hiatus site (~28 to 23 Ma). During this period of time, Australia’s climate would have been cool and dry before shifting to a more warmer and wetter setting in the Early Miocene. The environment inhabited by Badjcinus consisted of open temperate forests or woodlands, with patches of rainforest growing around forest pools and watercourses. Plant fossils indicate the presence of deciduous vine thickets and sclerophyllous vegetation.

The White Hunter and Hiatus sites have also yielded the remains of the thylacinids Ngamalacinus nigelmarveni and Nimbacinus peterbridgei, and the thylacoleonids Wakaleo schouteni and Lekaneleo roskellyae. The two families of carnivorous marsupials likely did not compete with each other due to differences in both body size and vertical habitat segregation. B. turnbulli is thought to have been an unspecialised faunivore that fed on small vertebrates and invertebrates. Whereas, the extremely deep jaws and worn teeth of B. timfaulkneri indicates that it was durophagous, possibly feeding on carrion.