Thursday, February 27, 2020

[PaleoMammalogy • 2020] Lekaneleo, A New Genus of Marsupial Lion (Marsupialia, Thylacoleonidae) from the Oligocene–Miocene of Australia, and the Craniodental Morphology of L. roskellyae, comb. nov.

 Lekaneleo roskellyae Gillespie, 1997

in Gillespie, Archer & Hand, 2020.
Original artwork by Peter Schouten.

The domestic cat-sized marsupial lion Priscileo roskellyae (Thylacoleonidae) from the Oligocene–Miocene of Australia was originally allocated to the genus Priscileo Rauscher, 1987, on the basis of its plesiomorphic upper dental formula of three premolars and four molars and its relatively small size. Recent reassignment of the Priscileo type species P. pitikantensis to the genus Wakaleo has now necessitated establishment of a new generic name for the species roskellyae Gillespie, 1997. In contrast to W. pitikantensis, which is only known from a fragmented palate and associated postcranial elements, the skull and lower dentition of P. roskellyae, described here, exhibit features that support its generic distinction within Thylacoleonidae. It is renamed here Lekaneleo roskellyae, comb. nov. Distinctive craniodental features include small sagittal and nuchal crests, lack of a prominent rostral tympanic process on the periotic, lack of alisphenopalatine pterygoid processes, a stylomastoid sulcus that courses through the mastoid, three teeth between i1 and p3, and very broad talonid basins on the lower molars. In contrast to species of Wakaleo, which appear to form a morphocline during the late Oligocene and early Miocene, L. roskellyae is a relatively conservative taxon, exhibiting no discernible change over the same interval of time.

Class MARSUPIALIA Illiger, 1811 
Order DIPROTODONTIA Owen, 1866 
Suborder VOMBATIFORMES Woodburne, 1984 

Family THYLACOLEONIDAE Gill, 1872 

LEKANELEO, gen. nov. 
Type and Only Species— Lekaneleo roskellyaecomb. nov.

Etymology— ‘lekane’ is derived from Greek meaning ‘basin’ and refers to the broad talonid basins present on the lower molars; ‘leo,’ which is Latin for ‘lion,’ is the stem term for all members of the family Thylacoleonidae. The genus is assigned feminine gender.

Priscileo roskellyae Gillespie, 1997: figs. 1–3.

Reconstruction of  Lekaneleo roskellyae hunting in the early Miocene rainforest at Riversleigh in northwestern Queensland
(Original artwork by Peter Schouten).

Anna K. Gillespie, Michael Archer and Suzanne J. Hand. 2020. Lekaneleo, A New Genus of Marsupial Lion (Marsupialia, Thylacoleonidae) from the Oligocene–Miocene of Australia, and the Craniodental Morphology of L. roskellyae, comb. nov. Journal of Vertebrate Paleontology.  DOI: 10.1080/02724634.2019.1703722