Permian/Triassic Age Reptiles and
Amphibians
http://www.reptileevolution.com/cephalerpeton.htm
MISSING LINK
http://macroevolution.narod.ru/_pamphibia.htm
Before the Dinosaurs, reptiles evolved into three main lineages.
First were the Parareptiles. Parareptiles showed primitive features and would eventually have the
turtles as its decendants.
Therapsids showed many mammal like characteristics and would eventually evolve into the Mammals.
Archosaurs included the thecodonts and would eventually evolve into the Dinosaurs, crocodilians and
birds.
The Permian age was named for the Perm region in Russia which was famous for its fossils of that
age. Other well known localities famous for their Permian faunas are South Africa and Texas and New
Mexico.
Museum of Arts and Sciences, Daytona Beach, Florida
the Russian National Collection
Garjania3.jpg
Garjainia triplocostata
240 mya
Rassypnaya
Orenburg Region
Russia
Garjainia was a Thecodont, an early representative of the Archisaurs, the group that eventually
included the Dinosaurs and Crocodilians and replaced the Therapsids(mammal-like reptiles).
Titanophoneus potens.JPG
Titanophoneus.jpg
Titanophoneus
potens
260-265 mya
Isheevo
Tatarstan
Titanophoneus, a therapsid was the top predator of its time.
biarmosuchus.JPG
Biarmosuchus.jpg
Biarmosuchus tener
260-265 mya
Ocher
Perm
Russia
Type specimen
Biarmosuchus, the size of a large dog, was a primitive predatory therapsid.
Inostranseveria.jpg
Inostrancevia
alexandri
250-255 mya
Malaya Severia
Arkangesk Reg.
North Russia
Type Specimen
Inostrancevia was a large sabre-toothed gorganopsid predator that had a more upright stance than
earlier therapsids.
Estemmenosuchus.jpg
Estemmenosuchus
uralensis
255 mya
Ocher
Perm
Russia
Estemmenosuchus was a large plant eating Therapsid (Mammal-like reptile) characterised by large
bumps or horns on its skull and a somewhat sprawling posture.
Estremmenosuchus.jpg
Rhabdiodromus.jpg
Rhadiodromus
klimova
230-235 mya
Berdyanka
Orenburg region
Russia
Rhadiodromus was a large tusked mammal-like reptile of the early Triassic.
Lystrosaurus.jpg
Lystrosaurus georgi
240 mya
Atashihka Nizhegorodskaya
Russia
Lystrosaurus appeared very early in the Triassic and spread very widely. Examples have been found
from Russia, India, Africa, to Antarctica. A plant-eating therapsid, Lystrosaurus had large feet, useful in
swampy areas..
Scutosaurus.jpg
Scutosaurus karpinski
250-255 mya
Sokolki
Arkangelsk
Russia
Scutosaurus, a very large barrel chested aquatic parareptile, is part of the lineage that eventually gave
rise to Turtles.
Scutosaurus2.jpg
Scutosaurus karpinski
250-255 mya
Sokolki
Arkangelsk
Russia
Lanthosuchus.jpg
(L) Lanthosuchus warsoni
260-255 mya
Isheevo, Tatarstan
(R) Deltavjatia viatkensis
250-255 mya
Perm Region,
Lanthosuchus was an aquatic parareptile with an extremely flattened skull. Deltavjatia was a terrestrial
parareptile showing many turtle like features, particularly in its skull
Parotosuchus.JPG
paratosuchus 2.
http://macroevolution.narod.ru/_pamphibia.htm
Paratosuchus.jpg
Parotosuchus
orenburgensis
235-245 mya
Orenburg region
South Russia
amphibian
Parotosuchus was an amphibian with a flattened skull and armored skin..
img005.jpg
http://faculty.evansville.edu/de3/b39902/PPoint/PermioTriassic/sld005.htm
Theriodonts
http://faculty.evansville.edu/de3/b39902/PPoint/PermioTriassic/sld005.htmhttp://en.wikipedia.org/wiki/
Theriodont
Theriodonts ("Beast Tooth", referring to more mammal-like teeth), are the third main group of
therapsids. They can be defined in traditional, Linnaean terms, in which case they are a suborder of
mammal-like reptiles that lived from the Middle Permian to the Middle Cretaceous, or in Cladistic
terms, in which case they include not only the traditional theriodonts but also their descendants the
mammals as well (in the same way that, cladistically speaking, the theropod dinosaurs include the
birds as a sub-clade).
Theriodonts appeared almost the same time as the anomodonts, about 265 million years ago, in the
Middle Permian. Even these early theriodonts were more mammal-like than their Anomodont and
Dinocephalian contemporaries.
anomodonts.JPG
260-Million-Year-Old Therapsid.JPG
Tiarajudens eccentricus is a newly described genus and species of herbivorous saber-toothed
anomodonts.
Tiarajudens is an herbivorous synapsid with saber-teeth
These teeth were probably used to scare off predators and intimidate them instead of using them for
offense or defense. These teeth would have little use on grinding up plants.
Paleontologists are certain that this was an herbivorous animal because of the surrounding teeth
around the gigantic canines - flat, grinding teeth.
It had a heterodont dentition, all of its teeth were different. Actually, this is a common character in the
class of Mammalia, the descendants of hairy synapsids.
Although, this is the earliest therapsid to have heterodont teeth.
It lived in the Middle Permian, ~260 ma, about 200 million years before the second earliest known
therapsid to have heterodont teeth.
Tiarajudens was found in southernmost Brazil, in what is now Rio Grande do Sul.
This therapsid is known from one specimen, its holotype, called UFRGS PV393P, a complete skull.
Tiarajudens was described by Juan Carlos Cisneros, Fernando Abdala, Bruce S. Rubidge, Paula
Camboim Dentzien-Dias, Ana de Oliveira Bueno in 2011.
"Tiaraju" is latin for "Tiarajú" while "dens" is latin for "tooth". The special name, eccentricus, is Latin for
"eccentric," due to its bizarre appearance.
Abstract - Anomodonts, a group of herbivorous therapsid “mammal-like reptiles,” were the most
abundant tetrapods of the Permian. We present a basal anomodont from South America, a new taxon
that has transversally expanded palatal teeth and long saber canines. The function of the saber teeth
is unknown, but probable uses include deterring attack from predators and intraspecific display or
combat. The complex palatal teeth were used to process high-fiber food and represent early evidence
of dental occlusion in a therapsid. This discovery provides new insight into the evolution of
heterogeneous dentition in therapsids and broadens our understanding of ecological interactions at
the end of the Paleozoic.
Reference - Cisneros, J.C.; Abdala, F.; Rubidge, B.S.; Dentzien-Dias, D.; Bueno, A.O. (2011). "Dental
Occlusion in a 260-Million-Year-Old Therapsid with Saber Canines from the Permian of Brazil".
Science 331: 1603-1605.
http://www.sciencemag.org/content/331/6024/1525.summary
http://www.sciencemag.org/content/331/6024/1525.figures-only
http://www.sciencemag.org/content/331/6024/1603.figures-only
Fig. 1
Cranium and dentition of T. eccentricus from the Permian of Brazil (UFRGS PV393P, holotype). (A)
Photograph and (B) drawing of the skull in lateral view. (C) Photograph and (D) drawing of the skull in
medial view (parasagittal section). (E) Saber canine in basal cross section; anterior is to the left. (F)
Incisiforms in lingual view (iii to v indicate tooth positions). (G) Palatal molariforms in occlusal view
(stereophotograph). (H) Lateral view of palatal teeth, showing a posterior-to-anterior replacement
sequence; replacement teeth are indicated by arrows. Scale bars, 50 mm for (A) to (D) and 10 mm for
(E) to (H). Abbreviations: an, angular; ar, articular; c, canine; ect, ectopterygoid; j, jugal; la, lacrimal; lf,
left frontal; ln, left nasal; lpm, left premaxilar; mx, maxilla; po, postorbital; pof, postfrontal; prf,
prefrontal; pt, pterygoid; q, quadrate; qj, quadratojugal; rf, right frontal; rn, right nasal; rpm, right
premaxilar; sa, surangular; sc, scleral ossicles; sm, septomaxilla; sq, squamosal; t, teeth.
Fig. 2
(A) Replacement palatal tooth in posterior view (last tooth in the row, apex to the top). (B and C)
Reconstruction of fourth palatal tooth, (B), posterior, slightly medial view, (C), occlusal view. (D) and
(E) Comparative figures showing a skull reconstruction of T. eccentricus (D) and the skull of the extant
saber-toothed water deer Hydropotes sp. (E). Scale bar, 10 mm for (A) to (C). (D) and (E) are not to
scale.
Fig. 3
Stratigraphically calibrated phylogeny of Permian basal anomodonts (5) and other therapsids. Circles
represent taxa known from a single locality. Values represented above the branches are decay values;
values below are from symmetric resampling. The temporal range of Dimetrodon extends to the
earliest Permian (Asselian). Abbreviations: Ciste., Cistecephalus; Chang., Changhsingian; Eodicyno.,
Eodicynodon; K, Karoo Assemblage Zone; Kungu., Kungurian; Prist., Pristerognathus; PTB, PermoTriassic Boundary; Road., Roadian; SGCS, Standard Global Chronostratigraphic Scale (27); Tropi.,
Tropidostoma; Wuchiaping., Wuchiapingian. Ages are in million years ago.
Dicynodont.jpg
http://blogevolved.blogspot.com/2009/04/synapsids-in-art.html
DicynodontevolutionRay.jpg
http://www.earthhistory.org.uk/transitional-fossils/reptile-to-mammal/
img006.jpg
http://faculty.evansville.edu/de3/b39902/PPoint/PermioTriassic/sld005.htmhttp://en.wikipedia.org/wiki/
Dicynodont
The Dicynodontia are a taxon of Therapsids or mammal-like reptiles. Dicynodonts were small to large
herbivorous animals with two tusks, hence their name, which means 'two dog tooth'. They are also the
most successful and diverse of the non-mammalian therapsids, with over 70 genera known, varying
from rat- to ox-sized.
Lycaenops
The sabre-toothed Lycaenops was a top predator of the latest Permian in South Africa. Lycaenops
was a gorgonopsian, one of a group of highly successful animals that dominated faunas in the Late
Permian, but were wiped out, together with 90 per cent of all species, by the end-Permian mass
extinction.
Photo: Mike Benton / University of Bristol
http://www.thedailygreen.com/environmental-news/latest/extinction-recovery-47011901
http://www.ucmp.berkeley.edu/synapsids/gorgonopsia.html
Despite their agility and fearsome teeth, the Gorgonopsia went extinct by the end of
the Permian, along with most other synapsid groups.
Lycaenops : One of the best studied gorgonopsians is Lycaenops. You can see the
mounted skeleton of this carnivore above
Notice that the legs are held close to the body as they are in mammals, and not out
to either side as in reptiles. The animal was about one meter long.
Gorgo+skeleton.jpg
http://blogevolved.blogspot.com/2009/04/synapsids-in-art.html
800px-Moschops.jpg
http://blogevolved.blogspot.com/2009/04/synapsids-in-art.html
IMG_3256.jpg
http://blogevolved.blogspot.com/2009/04/synapsids-in-art.html
Edaposaur.jpg
http://blogevolved.blogspot.com/2009/04/synapsids-in-art.html
edaposaur+skull.jpg
http://blogevolved.blogspot.com/2009/04/synapsids-in-art.html
IMG_3249.jpg
http://blogevolved.blogspot.com/2009/04/synapsids-in-art.html
last pelycosaur.JPG