Palæos: Paleozoic		Guadalupian Epoch
PERMIAN PERIOD		Capitanian Age

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The Capitanian Age

The Capitanian Age of the Guadalupian Epoch: 260 to 266 million years ago

Reefs

Tetrapods

The Tapinocephalus Assemblage Zone and Equivalents

According to Bakker, a high large herbivore diversity is indicated by the floodplain facies of the Tapinocephalus Zone of the South African Karroo, where five families or subfamilies and six genera are rather widespread and common; biomass D is about four. This high level of large herbivore diversity was to be also achieved by the radiations of the succeeding therapsid, therapsid-archosaur, dinosaur, and mammal empires. Each dynasty seems to have ended with a mass extinction, and, following a low diversity period, a new ecological community evolves.

As in the preceeding Wordian age, most of the big herbivores and carnivores were Dinocephalians. Many attained weights of a tonne or more, and lengths of 3 to 5 meters. The only other animals of comparable size were the Pareiasaurs, armoured herbivores specialised for a semi-aquatic existence, and possessing a truely bizarre cranial ornamentation. Accompanying these strange giants were a variety of smaller therapsids, lizard-like anapsids, and rare synapsids and diapsids.

In the north, the Isheevo Megafauna is probably contemporary with the Early Tapinocephalus Zone (sensu Boonstra), which is the period of greatest Dinocephalian diversity. Here there are two important genera, Doliosauriscus and Ulemosaurus, that appear to be synonymous with (although distinct at the species-level) the Karroo Anteosaurus and Moschops respectively (although it has also been suggetssed that Ulemosaurus may be more basal than Moschops). The more primitive characteristics of the northern fauna, and the preponderance of carnivores over herbivores, may be due to the more equitable climate and to it being more closely tied to water. Curiously, Pareiasaurs are absent from Isheevo; however they appear in the following, Kotelnich assemblage (perhaps equivalent to the Pristerognathus zone), where the epynomous Deltavjatia lends its name to the Deltavjatia vjatkensis Assemblage Zone

Known Distribution

The following map by Anderson and Cruikshank 1978 give the known distribution of Tapinocephalus age faunas. This refers only to the location of fossil remains. The actual distribution would naturally have been much wider.

cast of Emeroleter levis (Rhipeosaur)

Acme of the Therapsids

Endothiodon-Dicynodont Empire

Gorgonopsid mammal-like reptiles were common preditors of this time

For some unknown reason, all of the large herbivore families of the Dinocephalian Empire (Dynasty II - A-E in Fig.2), with the exception of the semi-aquatic pareiasaurs ), and corresponding very large predators (anteosaurids, A in Fig. 2), and the two most common and diverse medium-to-large carnivore families (D and E in Fig. 2) disappear abruptly together in the fossil record of the Karroo Basin in South Africa. This apparently massive extinction marks the division between the Tapinocephalus Zone and the Kistecephalus Zone in the Karroo, and between the Dinocephalian Empire (= Bakker's Dynasty II) and the Endothiodon-Dicynodont Empire (=Bakker's Dynasty III). It is not known if similiar mass-extinctions occured eslewhere, as the fossil record is patchy in its distribution, but later deposits from Russia and China show plenty of Endothiodon-Dicynodont forms, but not a single Dinocephalian.

In the earliest known post-Tapinocephalus Zone fauna of southern Africa (where the fossil record for late Permian tetrapods is most complete), new groups of big herbivores - the beaked and toothless dicynodonts - appear. These were clearly descended from those genera which were common but restricted to small body sizes during the Tapinocephalus Zone. Initial diversity of large dicynodonts may have been low, with one genus, Endothiodon, dominating some early local faunas. But within a relatively short period more big dicynodont families were added, and at the acme of Endothiodon-Dicynodont Empire (faunal stages 4 and 5 in Fig. 2) four fully terrestrial big families are common, plus pareiasaurs, the big aquatic herbivores that were the only survivors over 15 kg from the Dinocephalian empire. Biomass D rises during this period, and appears to reach maximum in the Capitanian age, some time before end of the Endothiodon-Dicynodont Empire. In the latest fauna (late Daptocephalus zone, Wuchiapingian age, stage 5 in Fig. 2) one genus, Daptocephalus, increases in relative frequency at the expense of the other big herbivores; thus local diversity, measured by D, decreases although all of the genera and families seem to be present right through to the end of the zone.

Only one family dominates the top predator role, the gorgonopsians, making up nearly all the specimens known (C in Fig. 2). Large gorgonopsids were present but very rare in the preceding Tapinocephalus Zone (Dinocephalian empire). The medium-size hipposaurids, also present in the Tapinocephalus Zone, were wide-spread but uncommon. Towards the end of this period, two more large predator families appear - the proterosuchid thecodonts (archosauriforms) and the therapsid moschorhinids (therocephalians). The latter make up about half the predator specimens in the latest Daptocephalus Zone faunas (late Wuchiapingian-early Changhsingian).

Some time during the Changhsingian age, the Endothiodon-Dicynodont empire is replaced by the Lystrosaur empire. In some instances Lystrosaurus and typically Dicynodon age animals opccur together, showing that this might be less a sudden mass extuinction and more a gradual transition. It is possible that the Lystrosaurus biota was better adapted to the increasingly arid climates of the end Permain

Known Distribution

The following map by Anderson and Cruikshank give the known distribution of Endothiodon and Dicynodon age faunas. This refers only to the location of fossil remains. The actual distribution would naturally have been much wider.