Ganbulanyi

Ganbulanyi Temporal range: Late Miocene PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Infraclass:	Marsupialia
Order:	Dasyuromorphia
Genus:	† Ganbulanyi Wroe, 1998
Species:	†G. djadjinguli
Binomial name
†Ganbulanyi djadjinguli Wroe, 1998

Ganbulanyi is an extinct genus of carnivorous marsupial from the Late Miocene of Australia. The only known species, Ganbulanyi djadjinguli , has been discovered at the Encore site in the Riversleigh World Heritage Area (north-western Queensland). Its teeth suggests that it was likely durophagous.

Discovery and naming

The holotype, QMF 24537, was found at the Encore site at the Riversleigh World Heritage Area, in the Boodjamulla National Park of northwestern Queensland. It consists of a fractured and worn upper first or second molar. In 1998, Stephen Wroe described this specimen as representing a new genus and species, which he named Ganbulanyi djadjinguli. ^[1] An upper second or third premolar was also referred to the taxon, but later became the type specimen for a new species of Malleodectes , M. moenia, in 2011. ^{[1] [2]}

The generic name is derived from the Waanyi word for “native cat”. The species name, pronounced “jad-jin-gulli”, is a combination of the Waanyi words for “to eat” (Djadji) and “bone” (nguli). ^[1]

Description

Ganbulanyi is distinguished from other dasyuromorphs primarily by various details of its molar. The upper molar is massive but low crowned. The occlusal (biting) surface of the protocone is small but robust, while the lingual face (side nearest the tongue) is steeply inclined. Viewed from the top of the tooth, the centrocrista is straight. The postmetacrista is aligned from front-to-back on the tooth. It retains stylar cusp C, but lacks stylar cusp E. All of the primary cusps are positioned close together. The stylar shelf is significantly small in size. ^[1]

G. djadjinguli was very similar in size to the Tiger quoll, being no larger than 7 kg (15.4 lbs). ^[1]

Classification

Wroe (1998) tentatively referred Ganbulanyi to the family Dasyuridae. In addition, a close relationship with Sarcophilus harrisii was hypothesised on the basis of two to four synapomorphies. However, some doubt was cast by the author as G. djadjinguli retains plesiomorphic traits such as an upper third premolar and stylar cusp C on its upper molar. ^[1] A study published in 2016 by Archer and colleagues noted similarities with the Malleodectidae but refrained from referring it to this clade due to substantial differences. ^[3]

Paleobiology

Fossils of Ganbulanyi known from the Encore site at the Riversleigh World Heritage Area, which has been estimated to be early Late Miocene in age. ^[4] At the time, Australia experienced less rainfall and rainforests either became fragmented or disappeared across the continent. The Riversleigh area would have been covered in woodland or open forest. ^[5] G. djadjinguli lived alongside other dasyuromorphs like Mayigriphus ; the phascolarctid Phascolarctos ; the vombatid Warendja ; the diprotodontid Neohelos ; the palorchestid Palorchestes ; the thylacoleonid Wakaleo ; the macropods Ekaltadeta and Wanburoo ; and the phalangerid Trichosurus . ^[4]

The dentition of Ganbulanyi exhbits adaptations towards hypercarnivory. Additionally, tooth wear suggests that it was also well suited for ‘bone-cracking’, a type of durophagy in which the animal is able to obtain to extract food contained in bony material. ^[6]

References

1. Wroe, S. (January 1998). "A new 'bone-cracking' dasyurid (marsupialia), from the Miocene of Riversleigh, northwestern Queensland". Alcheringa: An Australasian Journal of Palaeontology. 22 (3): 277–284. doi:10.1080/03115519808619205.
2. Derrick A. Arena; Michael Archer; Henk Godthelp; Suzanne J. Hand; Scott Hocknull (2011). "Hammer-toothed 'marsupial skinks' from the Australian Cenozoic". Proceedings of the Royal Society B . 278 (1724): 3529–3533. doi:10.1098/rspb.2011.0486. PMC   3189376 . PMID   21508033.
3. Archer, M.; Hand, S. J.; Black, K. H.; Beck, R. M. D.; Arena, D. A.; Wilson, L. A. B.; Kealy, S.; Hung, T.-t. (2016-05-27). "A new family of bizarre durophagous carnivorous marsupials from Miocene deposits in the Riversleigh World Heritage Area, northwestern Queensland". Scientific Reports. 6: 26911. Bibcode:2016NatSR...626911A. doi:10.1038/srep26911. ISSN   2045-2322. PMC   4882580 . PMID   27229325.
4. Myers, Troy; Crosby, Kirsten; Archer, Michael; Tyler, Michael (2001). "The Encore Local Fauna, a late Miocene assemblage from Riversleigh, northwestern Queensland". Memoirs of the Association of Australasian Palaeontologists. 25: 147–154.
5. Travouillon, K.J.; Legendre, S.; Archer, M.; Hand, S.J. (2009). "Palaeoecological analyses of Riversleigh's Oligo-Miocene sites: implications for Oligo-Miocene climate change in Australia". Palaeogeography, Palaeoclimatology, Palaeoecology. 276 (1–4): 24–37. doi:10.1016/j.palaeo.2009.02.025.
6. Archer, M.; Christmas, O.; Hand, S.J.; Black, K.H.; Creaser, P.; Godthelp, H.; Graham, I.; Cohen, D.; Arena, D.A.; Anderson, C.; Soares, G.; Machin, N.; Beck, R.M.D.; Wilson, L.A.B.; Myers, T.J.; Gillespie, A.K.; Khoo, B.; Travouillon, K.J. (2016). "Earliest known record of a hypercarnivorous dasyurid (Marsupialia), from newly discovered carbonates beyond the Riversleigh World Heritage Area, north Queensland". Memoirs of Museum Victoria. 74: 137–150. doi: 10.24199/j.mmv.2016.74.13 . hdl: 1959.4/unsworks_41915 .