Price et al.: koala palaeoecology 
43 
Fig. 3. Morphometries of fossil koala specimens. (A) Depth versus width of dentaries of modern Phascolarctos 
cinereus from eastern Queensland (Appendix), fossil Cundokoala ( ?Ph .) yorkensis (SAMP24904) from Corra 
Lynn Cave (South Australia), and phascolarctid gen et. sp. indet (QMF52287) from Chinchilla, eastern Australia. 
Note that the depth of the Chinchilla koala dentary is a minimum measurement because the specimen is broken 
along the alveolar border (Fig. 2). ( B ) Anterior versus posterior width of Phascolarctos spp. M 2 (See Appendix 
for list of modem Ph. cinereus specimens examined). 
single large pit. Comparison of QMF52287 to other large¬ 
sized phascolarctids such as Ph. maris, or unusual koala-like 
marsupials such as Koobor, is not possible because dentaries 
of those taxa are unknown. 
Genus Phascolarctos Blainville (1816) 
Diagnosis. Upper molars of Phascolarctos differ from all 
other phascolarctids (excepting Cundokoala ( ?Ph .) york¬ 
ensis) and the koala-like Koobor by: (a) being larger; (b) being 
relatively higher crowned; (c) by possessing well-developed 
molar crenulations; and ( d) possessing well-developed ribs 
on lingual portion of paracone and metacone. 
Phascolarctos differs from Madakoala, Nimiokoala 
and Koobor by possessing a lingual cingulum or pocket on 
upper molars at the crown base between the protocone and 
metaconule. 
Phascolarctos differs from Litokoala and Nimiokoala 
by possessing relatively smaller neometaconules and 
paraconules. 
Phascolaractos differs from Madakoala, Perikoala, 
Cundokoala and Koobor by possessing relatively smaller 
or weakly expressed stylar cusps, and in the case of 
Cundokoala, by possessing a relatively less-developed 
associated stylar shelf. 
Phascolarctos differs from Cundokoala in being smaller 
and by possessing lesser-developed molar crenulations. 
Phascolarctos differs from Koobor by: (a) having a 
square- to trapezoidal-shaped, rather than rectangular¬ 
shaped, occlusal outline; ( b ) possessing relatively longer 
anterior and posterior cingula; and (c) lacking a buccal 
ectoloph on the paracone. 
Phascolarctos sp. 
Figs 3B, 4A 
Referred material. QMF52288, isolated LM 2 , QML1384 
(Unit “L.U.”; Elephant Hole Cave), Mt. Etna, central eastern 
Queensland, Australia (Middle Pleistocene; Table 1) 
Description. LM 2 with anterior portion missing; tooth 
trapezoidal in occlusal outline, tapering posteriorly; 
protocone and paracone sub-equal in height, slightly taller 
than metacone and metaconule, neometaconule shortest 
cusp; protocone most anterior cusp forming anterolingual 
comer of tooth; paracone transverse, slightly posterior to 
protocone, forming anterobuccal margin of tooth; metacone 
directly posterior to paracone forming posterobuccal corner 
of tooth; metaconule posterobuccal to protocone, transverse 
to metacone, forming posterolingual corner of tooth; 
postprotocrista well developed, descends posterobuccally 
from apex of protocone to meet with premetaconulecrista; 
cristae on paracone missing; rib descends posteriorly 
from apex of paracone to mid-crown basin; premetacrista 
well developed, descends anterobuccally from apex of 
metacone, terminating at stylar cusp D; postmetacrista well 
defined, descends posterobuccally from apex of metacone; 
posterolingual crista weakly-expressed descending from 
metacone apex to posterolingual base of metacone; 
neometaconule small, distinct at anterolingual base of 
metacone; premetaconulecrista well developed, descends 
anterobuccally from apex of metaconule terminating at 
midcrown basin; postmetaconulecrista well developed, 
descends posterobuccally from apex of metaconule, 
with inflexion at posterior cingulum; lingual cingulum 
moderately developed at base of crown between protocone 
and metaconule; posterior cingulum well defined, descends 
from inflexion with postmetaconulecrista, terminating at 
posterobuccal comer of tooth near stylar cusp E; metacone 
