Thylacinus yorkellus is a moderately small-bodied species of thylacinid
from the latest Miocene or, more likely, earliest Pliocene of South Australia
(Curramulka Local Fauna). This recently described species is shown
via cladistic analysis to be the sister species of T. cynocephalus,
and distinct from the approximately contemporary T. megiriani from
the Northern Territory. New dentary material was described by Yates
(2015). Each of the three known late Miocene to early Pliocene Thylacinus
species (T. potens, T. megiriani and T. yorkellus)
suggest that, instead of declining, there was a modest radiation of Thylacinus
in the late Miocene.
holotype specimen (SAM P29807) of Thylacinus yorkellus, an incomplete
left dentary, in (A) lateral, (B) medial, and (C) dorsal view. Scale
bar = 50 mm. Photo: Steven Jackson. (Yates, 2015).
rothi is a Late Miocene thylacinid that was found at the Alcoota Scientific
Reserve (Alcoota Local Fauna), Northern Territory. Its specific name
honors Karl Roth for his contributions to the natural history of central
Australia. The holotype specimen is a left maxillary fragment containing
P2 and damaged M1-4. It was reassembled from a concentration of small
bone and tooth fragments, which according to Murray and Megirian (2000),
may represent the contents of a crocodilian coprolite (fossilized dropping).
Many of the fragments exhibit chemical erosion and bear a coating of calcite.
is considered to be more closely related to species of Thylacinus
than to other thylacinid genera. Possibly, T. rothi lived
contemporarily in the same habitat as the much larger and more derived
potens, which is also known from the Alcoota Local Fauna.
An Early Miocene thylacine
from Riversleigh (Camel Sputum Site, Camel Sputum Local Fauna) whose species
name honors David Ride, who made the first revision of thylacinid fossils
holotype left maxillary fragment of Tyarrpecinus rothi in lateral
(top) and occlusal (bottom) view.
(Murray and Megirian 2000).
|W. ridei was described on the basis
of right maxillary fragment containing M1-2 and a left dentary fragment
with M3. This species is more specialized than Muribacinus,
and Ngamalacinus but more primitive than Thylacinus.
The Kutjamarpu thylacinid:
An isolated premolar,
discovered in 1971 at the Leaf Locality of the Wipijiri Formation, Lake
Ngapakaldi, Etadunna Station, South Australia, would appear to represent
a thylacinid. The fauna of the Leaf Locality is called the Kutjamarpu
Local Fauna (Stirton et al.1967), is of Miocene
age, and is interpreted by M. O. Woodburne to be approximately 12 million
years old. Only a very limited amount of phylogenetically significant
information can be gleaned from this tooth. Several additional collecting
trips have been made to the Leaf Locality, but no more complete specimens
of this species have been found (Archer 1982).
Further details about
Miocene thylacinids can be found in Murray and Megirian's paper "Two
new genera and three new species of Thylacinidae (Marsupialia) from the
Miocene of the Northern Territory, Australia", which is available for
viewing online (PDF).