| Thylacinus megiriani:
This species lived during
the Late Miocene, and was discovered at Alcoota (South Quarry, Ongeva Local
Fauna), in the Northern Territory.
section of the cranium of Thylacinus megiriani, including several
maxillary teeth. Courtesy: Museum of Central Australia.
The remains of Thylacinus are very rare at Alcoota, although there
were forests and a permanent water supply there during T. megiriani's
time some 8 million years ago. Palaeontologists have found many fossil
bones at this site which are densely packed together from animals that
died within a space of just a few years. It is theorized that a period
of very unpredictable climate occurred at Alcoota during the Late Miocene,
and that there was little or no rain for several years in the area.
Thylacinus potens, whose name means "powerful thylacine", is the largest
thylacinid species known to have existed. Preceding T. cynocephalus
by about 4-6 million years, its remains are known only from a single Late
Miocene locality (Alcoota) near Alice Springs, Northern Territory.
This thylacine had a considerably more massive build than the modern species,
and a somewhat shorter, broader skull. Its teeth also show some slight
differences in morphology, and appear to be not quite as specialized for
shearing as those of T. cynocephalus (Archer
life reconstruction of Thylacinus potens. The pattern of the
stripes is purely speculative - as is the case with other fossil species
known only from their bones, we can only theorize about their coat patterns
based upon living species. Courtesy: Anne Musser.
| Woodburne (1967)
states that T. potens is quite similar to thylacines of Quaternary
(our current geological time period) age, but in its possession of "...small
palatal fenestrae, the presence of a stylar cusp anterior to the metastyle
of M3, the more symmetrical arrangement of the parts of the upper molars
and the strong cleft in the labial outline of the upper molars...",
these character states in the Miocene species "...could be interpreted
as primitive features relative to a remote dasyurid ancestry".
Material: Woodburne (1967) has given
a comprehensive description of the holotype
specimen, a poorly preserved rostrum including a palate and damaged dentition.
The fossil was found at Paine Quarry, Alcoota Homestead, in the Northern
Territory. Some dentary fragments also exist (University of California,
Berkeley, paleontological collections), but these are far less complete
than the rostrum. A few additional mandibular fragments and a small
section of the premolar region of a maxilla of a second skull were found
on a subsequent visit to Alcoota in 1975 (the Ray E. Lemley Expedition
to Alcoota). These new specimens (Queensland Museum) however, add
little to the concept of the species as known by Woodburne (1967).
Alcoota Local Fauna, from the Waite Formation, is interpreted to be of
Late Miocene age (approx. 7 million years old). This fauna is dated
on the basis of comparison with other dated faunas. On this basis,
it is older than the Early Pliocene local faunas, such as the Chinchilla,
Bluff Downs, Bow and Hamilton faunas but younger than the array of Middle
Miocene local faunas such as the Tarkarooloo, Pinpa, Ngapakaldi and Ericmas
faunas (dated at around 15 million years old). As of yet however,
there is no means of establishing an absolute date for the Alcoota Local
palatal view of the holotype specimen of
Thylacinus potens Woodburne.
life reconstruction of a hunting Thylacinus potens pair. Courtesy: