| Cisuralian Epoch | ||
| Paleozoic: Permian Period |
Artinskian Age |
| Sakmarian | Pennsylvanian | Cisuralian | ||
| Kungurian | Guadalupian | Time |
As the climate became drier, the early Permian semiaquatic and lowland floodplain Dimetrodon and Eryops dominated fauna shown above, which had flourished for some 25 million years, was replaced by the more advanced floodplain and upland caesid and therapsid fauna.
 |
This map shows the three known tetrapod provinces (shaded) of the early Permian - the tropical Edaphosaurid (centre), the Kazakhstan Seymouriamorph province (upper right), and the high latitude Gondwana Mesosaurid province (bottom) From A.R. Milner, "Biogeography of Palaeozoic Tetrapods" fig.13.3; in J.A. Long (ed.) Palaeozoic Vertebrate Biostratigraphy and Biogeography, 1993, John Hopkins University Press, Baltimore |
Age |
Tetrapod zone |
Time* |
Location |
||||||
| USA |
Western Europe |
Eastern Europe |
Brazil |
southern Africa |
India |
||||
Texas |
Oklahoma |
Germany |
Parana Basin |
South Africa / South-West Africa |
Himalayas |
||||
Biotic province |
|||||||||
Edaphosaurid province |
|
|
Mesosaurid province |
|
|||||
Baigendzhinian |
10 |
277
278
279 |
Choza |
Hennesey |
|
|
|
|
|
9 |
Vale |
|
|
|
|
|
|||
8 |
Arroyo |
Garber |
|
zone 0 |
|
|
|
||
Aktasinian |
7 |
280
281
282
283 |
Ludens |
West Grandfield |
|
|
|
|
|
6 |
Clyde |
Deep Red Run |
|
|
Irati |
White band |
|
||
5 |
Belle Plains |
Wellington formation |
|
|
|
|
|
||
|
This table is based on J. M. Anderson & A. R. I. Cruikshank, "The Biostratigraphy of the Permian and Triassic, Part 5, a review of the classification and distribution of Permo-Triassic Tetrapods", in Paleontologica Africana, 21, 15-44 (1978); slightly modified. * approximate time in MYA (millions of years ago) - nearest million year intervals | |||||||||
 |
Early Permian Bestiary - Edaphosaurid-Nectridean Province Illustration by Robert Bakker |
Class Chondrichthyes
Subclass Elasmobranchii
Order Xenacanthida
Family Xenacanthidae
Standard total length of about 1 to 2 meters
Predator of aquatic vertebrates
Class Tetrapoda
Order Temnospondyli
Superfamily Eryopoidea
Family Eryopidae
Wichita Series (Wolfcampian age), Texas Red Beds
Standard total length from 1.5 to 2 meters
about 130 kg
Predator of other tetrapods
a large long-lived aquatic temnospondyl
Dimetrodon grandis
Plesion Synapsida (Theropsida)
Order Pelycosauria
Suborder Eupelycosauria
Family Sphenacodontidae
Arroyo Formation, Clear Fork Group
Texas, USA
Skull measures 42 cm long. Standard total length of 3.2 metres
around 250 kg
Predator of other tetrapods
The last and largest of the long-skulled, stocky-bodied lineage of dimetrodonts. Apart from D. angelensis this was the largest species of Dimetrodon. A large, heavily-built, very common species, it is close to the earlier D. limbatus, with which it differs in larger size, more elongate and stouter neural spines, and fewer premaxillary teeth (only two on either side, the fewest for any species of the genus). It is associated with the slightly smaller but equally successful Dimetrodon gigashomogenes
Dimetrodon gigashomogenes
Plesion Synapsida (Theropsida)
Order Pelycosauria
Suborder Eupelycosauria
Family Sphenacodontidae
Arroyo, Vale and Choza Formations, Clear Fork Group
Texas, USA
Standard total length of 328 cm
around 166 kg
Predator of other tetrapods
A large representative of the short-skulled lineage of dimetrodonts. Possibly ancestral to D. angelensis. Although similar in size to Dimetrodon grandis, it differs in the shape of the neural spines, the length of the vertebrae centra, and the lighter overall build. D. gigashomogenes would seem to be a descendent, or possibly even the same species, of the preceding D. dollovanus, from which it differs mainly in larger size.