| Nimbacinus richi:
The only other species
of Nimbacinus yet described, N. richi is from the Middle
Miocene deposits of Bullock Creek ("Top Site", Bullock Creek Local Fauna),
Northern Territory. The holotype specimen is a well preserved right
dentary containing teeth P1 through M4. N. richi is distinguished
from N. dicksoni on the basis of some minor details of dental morphology,
and its status as a distinct species is currently under debate (Wroe
and Musser 2001).
lateral view of molars M1-4 in the holotype dentary (lower jaw) of N.
richi. (Murray and Megirian 2000).
Fossilized remains of
the modern thylacine species T. cynocephalus, dating from the Pleistocene
epoch, are known from many sites across Australia, including Tasmania and
Papua New Guinea. The exceptional example shown in the photographs
below is a cranium found in the Yarrangobilly Caves of Mount Kosciuszko
National Park, NSW in 1969. Notable localities for T. cynocephalus
fossils include the Naracoorte Caves (SA) and Wellington Caves (NSW).
For further details about the ancient distribution of the species, see
the subsection Prehistoric
Range of the Thylacine.
Pleistocene-age thylacine skull (large male) in dorsal, palatal and lateral
The roof of the skull appears
to have been gnawed by a rodent, possibly prior to fossilization.
Janus Cave (Yarrangobilly
Caves), Mount Kosciuszko National Park, NSW. Specimen ANWC M15266.
Courtesy: Australian National
Wildlife Collection (Canberra).
Photos: International Thylacine
Specimen Database Fifth Revision, 2013.
| T. macknessi
lived during the Early Miocene. Its fossils were found in north-western
Queensland at the Riversleigh World Heritage area (Neville's Garden Site,
Neville's Garden Local Fauna). The oldest known member of the genus
its species name honors Brian Mackness, a ong-time supporter of Australian
vertebrate palaeontology. The holotype specimen of
nearly complete right dentary (lower jaw) in which all teeth are present
except for the incisors. When the species was first described, only
the posterior section of the jaw (bearing the last three molars) was known.
Luckily, the anterior half of the holotype specimen was found two years
later in a block of limestone from the same fossil site (Muirhead
and Gillespie 1995). In some respects, this species is more
specialized than more recent members of its genus, which suggests that
a common ancestor of all species of Thylacinus must have been older
than T. macknessi.
section of the lower jaw from one of the larger species of fossil thylacines
found at Riversleigh is shown here above the jaw of a modern thylacine
(T. cynocephalus) for comparison.