Late Oligocene - Middle Miocene
Priscileo is the smallest of all
thylacoleonids, being only about the size of a possum or cuscus.
The genus Priscileo is currently represented by only one species,
- The oldest and most primitive
member of the family Thylacoleonidae yet found. It is known only
from a rather poorly preserved fossil maxillary fragment and a few post-cranial
bones recently found in the Late Oligocene Ngapakaldi Local Fauna at Lake
Pitakanta in northeastern South Australia.
Members of the genus Wakaleo were
approximately the size of a dingo or other medium-sized dog.
alcootaensis - This
species comes from the Alcoota Local Fauna of the Northern Territory.
It was slightly larger in size than W. oldfieldi and W. vanderleueri
(see below). The sole representative fossil of this species (a fragmentary
maxilla) was found in 1974 in the Miocene Waite Formation (Alcoota Local
Fauna) by Dr. Michael Archer.
The maxillary fragment shown at right is
the holotype (the single specimen designated by an author as the type of
a species) of W. alcootaensis
oldfieldi - In 1971,
a group of paleontologists, working in the Miocene Wipijiri Formation (Kutjamarpu
Local Fauna, South Australia) discovered a nearly complete left dentary
of this species which retained a number of rather well preserved teeth.
A small number of isolated teeth have also been recovered.
Illustrated is the mandible described above.
vanderleueri - The
first fossil material of this species (a right dentary fragment) was found
in 1967 by a group of field workers from the Bureau of Mineral Resources
working in the Miocene Camfield Beds of the Northern Territory (Bullock
Creek local fauna). Since then, quite a number of additional specimens
have been found. Among these is the magnificently preserved, nearly
complete cranium with associated mandible shown in the photograph.