Protemnodon Explained

Protemnodon is an extinct genus of megafaunal macropodids that existed in Australia, Tasmania, and New Guinea in the Pliocene and Pleistocene. Members of this genus are also called giant kangaroos.

Taxonomy

Recent analysis of mtDNA extracted from fossils indicates that Protemnodon was closely related to Macropus.^[1] The species formerly known as Protemnodon bandharr and Protemnodon buloloensis have been moved to a new genus, Silvaroo, while the New Guinean species P. nombe has been moved to the new genus Nombe.^[2]

A 2024 review of the genus recognized seven valid species, including three new ones:

• P. anak Owen, 1874 (type species)
• P. otibandus Plane, 1967
• P. snewini Bartholomai, 1978
• P. tumbuna Flannery et al., 1983
• P. mamkurra Kerr et al., 2024
• P. viator Kerr et al., 2024
• P. dawsonae Kerr et al., 2024

P. chinchillaensis and P. hopei were considered junior synonyms of P. otibandus and P. tumbuna respectively. P. brehus, P. roechus, P. mimas, P. antaeus, and P. devisi were considered nomina dubia.^[3]

Description

Based on fossil evidence, Protemnodon is thought to have been physically similar to wallabies, but generally larger and more robust. Protemnodon roechus was the largest in the genus, weighing around 170 kg.^[4]

Some studies show that Protemnodon species ranged from efficient hoppers of dry open habitats (such as P. viator) to slower, more quadrupedal forest dwellers (like P. tumbuna), while others have found that even species such as P. viator were very inefficient hoppers and primarily quadrupedal.^[5] The shape and articulation of the forelimbs suggests that they may have been adept at digging, while the claws on their hind feet had a curved shape, perhaps to help stabilise the animal on uneven ground.^[5]

Several species of Protemnodon survived up until around 50,000 years ago. P. tumbuna may have survived in the highlands of Papua New Guinea as recently as 12,000 years B.P.^[6]

Notes and References

1. Llamas . B. . Brotherton . P. . Mitchell . K. J. . Templeton . J. E. L. . Thomson . V. A. . Metcalf . J. L. . Armstrong . K. N. . Kasper . M. . Richards . S. M. . Camens . A. B. . Lee . M. S. Y. . Cooper . A. . 2014-12-18 . Late Pleistocene Australian marsupial DNA clarifies the affinities of extinct megafaunal kangaroos and wallabies . . 32. 3 . 574–584. 10.1093/molbev/msu338 . 25526902. free.
2. Kerr . Isaac A. R. . Prideaux . Gavin J. . 2022-06-29 . A new genus of kangaroo (Marsupialia, Macropodidae) from the late Pleistocene of Papua New Guinea . Transactions of the Royal Society of South Australia . 146 . 2 . 295–318 . 10.1080/03721426.2022.2086518 . 2022TRSAu.146..295K . 250189771 . 0372-1426.
3. Kerr . Isaac A.R. . Camens . Aaron B. . Van Zoelen . Jacob D. . Worthy . Trevor H. . Prideaux . Gavin J. . 2024-04-15 . Systematics and palaeobiology of kangaroos of the late Cenozoic genus Protemnodon (Marsupialia, Macropodidae) . Megataxa . 11 . 1 . 1–261 . 10.11646/megataxa.11.1.1 . 2703-3090. free .
4. Helgen, K.M. . Wells, R.T. . Kear, B.P. . Gerdtz, W.R. . Flannery, T.F. . amp . 2006 . Ecological and evolutionary significance of sizes of giant extinct kangaroos . Australian Journal of Zoology . 54 .
   1. 4
   . 293–303 . 10.1071/ZO05077.
5. Jones . B. . Janice . C.M. . June 2024 . Hop, walk or bound? Limb proportions in kangaroos and the probable locomotion of the extinct genus Protemnodon . Journal of Mammalian Evolution . 31 . 26 . 10.1007/s10914-024-09725-4. free .
6. Flannery . T.F. . Mountain . M-J. . Aplin . K. . Quaternary kangaroos (Macropodidae: Marsupialia) from Nombe rock shelter, Papua New Guinea, with comments on the nature of megafaunal extinction in the New Guinea highlands . Proceedings of the Linnean Society of New South Wales . 1983 . 107 . 2 . 75–97 .