Material that represents the fossil component is the MP1 horizon in a sequence of lacustrine clays from Boat Mountain. The geological formation of the site is not known for certain, but may be associated with the Oakdale Sandstone formation. The area was a swamp or shallow lake at the time of deposition, though the habitat has not been determined. Potassium-argon dating of illites has given a date of about 54.6 million years, which is before Australia's separation from Antarctica and South America[2]
Costal tubercle is broken so not able to determine if it was robust as in madtsoiids or slender in proximal view as with the extent serpentes. Some other characteristics indicate a Patagoniophis affinity excluding the large size (3.9 by 2.6 mm), but is still smaller than Madtsoia, to which it is most similar.[4]
QM specimens F20688 (carpometacarpus) and F24685 (tibiotarsus) from Murgon, Queensland, are fossil bone fragments clearly recognizable as passeriform; they represent two species of approximately some 10 and some 20 cm in overall length.[8]
^Scanlon, J. D. 2005. Australia's oldest known snakes: Patagoniophis, Alamitophis, and cf. Madtsoia (Squamata: Madtsoiidae) from the Eocene of Queensland. Memoirs of the Queensland Museum (Proceedings of the Conference of Australasian Vertebrate Evolution, Palaeontology and Systematics) v. 51, p. 215–223.
^Godthelp, H.; Archer, M.; Cifelli, R.; Hand, S. J.; Gilkeson, C. F. 1992. "Earliest known Australian Tertiary mammal fauna". Nature 359:514-516 doi:10.1038/356514a0
^Boles, Walter E. (1997): "Fossil Songbirds (Passeriformes) from the Early Eocene of Australia". Emu97(1): 43-50. doi:10.1071/MU97004
^Vanesa L. De Pietri, R. Paul Scofield, Nikita Zelenkov, Walter E. Boles and Trevor H. Worthy (2016). "The unexpected survival of an ancient lineage of anseriform birds into the Neogene of Australia: the youngest record of Presbyornithidae". Royal Society Open Science. 3 (2): 150635. doi:10.1098/rsos.150635.
Further reading
Scanlon, J. D. (2005). "Australia's oldest known snakes: Patagoniophis, Alamitophis, and cf. Madtsoia (Squamata: Madtsoiidae) from the Eocene of Queensland". Memoirs of the Queensland Museum. 51 (1): 215–235. ISSN0079-8835.