Week 11 Flashcards
Anapsids
no fenestrae like turtles
synapsids
one fenestrae (lateral) all mammals and reptiles
diapsids
two fenestrae
two supgroups
-lepidosauromorphs (regular)
-Archosauromorphs (antorbital and mandibular fenestra
Dimetrodon
(permian) was the first synapsid
had three lineages
-Gorgonopsids (saber toothed)
-Dicynnodonts (tusked herbivores)
-Cyanodonts (became mammals)
archosauromorphs
are diapsids with antorbital and mandibular fenestae
-crocodiles, birds, Dinos and pterosaurs
avemetatarsalians
are archosaurs that have hinge like ankles
-stiffer to support lots of weight in upright stance
-dinosaurs, birds, pterosaurs
pseudosuchian
are archosaurs that have a peg and socket like ankle joint
-crocodiles
Permian extinction
killed lots via heat or something
-but left many niches open so synapsids took top status with Cynodonts and dicynodonts (surviving)
-but then diapsid archosaurs rose and took over an ancestor of crocodilian pseudosuchians
Pseudosuchian
large group coming from diapsid archosaurs after the permian extinction
phytosaurs,aetosaurs, rauischids, prestoschians, poposuroids
phytosaurs
Pseudosuchian
-similar to crocodiles
contains Smilosuchus
Aetosaurs
Pseudosuchian, armoured and herbivorous
contains, desmatosuchus
Rauisuchids
Pseudosuchian, terrestrial with upright posture
Prestoschians
Pseudosuchian, terrestrial with upright posture
Poposuroids
has the sail on back
-Poposaurus
Silesaurids
very early from the archosaurs
-small and bipedal with no hole in hip
