Anomodont
Encyclopedia
The Anomodontia were a major group of therapsids, an extinct group of animals commonly known as "mammal-like reptiles." They were mostly toothless herbivores. During the Middle Permian they were very diverse, including groups like the Venyukovioidea
, the Dromasauria
, the Dicynodont
ia, and early very primitive forms like Anomocephalus and Patranomodon. Of these only the Dicynodonts survived to the Late Permian, and became the most successful and abundant of all Permian herbivores, filling ecological niches ranging from large browsers down to small burrowers. Only two dicynodont families survived the Permian–Triassic extinction event, one of which, the Lystrosauridae
, soon gave rise to the Kannemeyeridae. These latter were large, stocky, beaked animals that remained the dominant terrestrial herbivore right up until the Late Triassic
, when changing conditions (perhaps increasing aridity) caused them to decline and eventually die out.
In March 2011, scientists in Brazil discovered the 260-million-year-old fossils of a unique saber-tooth vegetarian. The mammal-like reptile, with the scientific name Tiarajudens
eccentricus, used two large fangs at the front of its mouth for shredding and tearing and also probably to ward off predators, but not to eat meat. The fossils are from the extinct Anomodontia suborder within the Therapsida order, four-footed species who dominated during the Permian period, before the dinosaur age. The fossil remains indicate that the snout-nosed creature was slightly larger than the size of a wild boar.
modified from Liu et al. (2009):
Venyukovioidea
Venyukovioidea is an infraorder of anomodont therapsids from the Permian of Russia. It includes the genera Otsheria, Venyukovia, Ulemica, and Suminia. Venyukovioidea and Dromasauria were traditionally considered the two main groups of basal anomodonts. Dromasauria was considered a Gondwanan group...
, the Dromasauria
Dromasauria
Dromasaurs are a paraphyletic group of anomodont therapsids from the Middle Permian. They were small with slender legs long tails. Their skulls were short, but the eye sockets were large. Dromasauria was once considered to be a major group of basal anomodonts along with the infraorder Venyukovioidea...
, the Dicynodont
Dicynodont
Dicynodontia is a taxon of anomodont therapsids or mammal-like reptiles. Dicynodonts were small to large herbivorous animals with two tusks, hence their name, which means 'two dog tooth'...
ia, and early very primitive forms like Anomocephalus and Patranomodon. Of these only the Dicynodonts survived to the Late Permian, and became the most successful and abundant of all Permian herbivores, filling ecological niches ranging from large browsers down to small burrowers. Only two dicynodont families survived the Permian–Triassic extinction event, one of which, the Lystrosauridae
Lystrosauridae
Lystrosauridae was a family of Synapsids from the Permian and Triassic time periods.-Distribution:-Triassic Distribution:In the Triassic period, Lystrosaurids lived in Antarctica and China.-Relatives:...
, soon gave rise to the Kannemeyeridae. These latter were large, stocky, beaked animals that remained the dominant terrestrial herbivore right up until the Late Triassic
Triassic
The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...
, when changing conditions (perhaps increasing aridity) caused them to decline and eventually die out.
In March 2011, scientists in Brazil discovered the 260-million-year-old fossils of a unique saber-tooth vegetarian. The mammal-like reptile, with the scientific name Tiarajudens
Tiarajudens
Tiarajudens is an extinct genus of saber-toothed herbivorous anomodont which lived during the middle Permian period in what is now Rio Grande do Sul, Brazil. It is known from the holotype UFRGS PV393P, a nearly complete skull. The type species T...
eccentricus, used two large fangs at the front of its mouth for shredding and tearing and also probably to ward off predators, but not to eat meat. The fossils are from the extinct Anomodontia suborder within the Therapsida order, four-footed species who dominated during the Permian period, before the dinosaur age. The fossil remains indicate that the snout-nosed creature was slightly larger than the size of a wild boar.
Taxonomy
- Order Therapsida
- SUBORDER ANOMODONTIA
- AnomocephalusAnomocephalusAnomocephalus is an extinct genus of primitive anomodont. Anomocephalus is primitive in that it retains a complete set of teeth in both jaws, in contrast to its descendants, the dicynodonts, in which the dentition is reduced to only a single pair of tusks , with their jaws covered by a horny beak...
- PatranomodonPatranomodonPatranomodon is an extinct genus of primitive anomodont. Patronomodon is primitive in that it retains a complete set of teeth in both jaws, in contrast to their descendants, the dicynodonts, in which the dentition is reduced to only a single pair of tusks , with their jaws covered by a horny beak...
- Venjukoviamorpha
- Family Otsheridae
- OtsheriaOtsheriaOtsheria is an extinct genus of anomodont from the Permian of Russia.-References:*The Origin and Evolution of Mammals by T. S. Kemp...
- Suminia
- Otsheria
- Family Venjukoviidae
- UlemicaUlemicaUlemica is an extinct genus of venjukoviid therapsid. It was a basal member of the suborder Anomodontia that existed during the Late Permian in Russia. The type species, U. invisa, was assigned to the genus Venjukovia prior to being placed within its own genus in 1996.-References:*...
- VenjukoviaVenjukoviaVenjukovia is an extinct genus of non-mammalian synapsid from the Middle Permian of Russia.-References:*...
- Ulemica
- Family Otsheridae
- Infraorder DromasauriaDromasauriaDromasaurs are a paraphyletic group of anomodont therapsids from the Middle Permian. They were small with slender legs long tails. Their skulls were short, but the eye sockets were large. Dromasauria was once considered to be a major group of basal anomodonts along with the infraorder Venyukovioidea...
- Family Galeopidae
- GalechirusGalechirusGalechirus is an extinct genus of therapsid mammal-like reptile. It was about 30 cm long.This lizard-like creature is considered to be a dicynodont by some paleontologists; others think Galechirus is the young of a larger therapsid genus. Judging from its teeth, it was an insectivore....
- GaleopsGaleopsGaleops is an extinct genus of therapsid....
- GalepusGalepusGalepus is an extinct genus of therapsid....
- Galechirus
- Family Galeopidae
- Infraorder DicynodontDicynodontDicynodontia is a taxon of anomodont therapsids or mammal-like reptiles. Dicynodonts were small to large herbivorous animals with two tusks, hence their name, which means 'two dog tooth'...
ia- Family Endothiodontidae
- Family Eodicynodontidae
- Superfamily Kingorioidea
- Family Kingoriidae
- DiictodontiaDiictodontiaThe Diictodontia were a group of herbivorus Dicynodonts from the Permian of South Africa. This infraorder was composed of three different families; Diictodontidae , Emydopidae, and Robertiidae....
- Superfamily Emydopoidea
- Family Cistecephalidae
- Family Emydopidae
- Superfamily Robertoidea
- Family Diictodontidae
- Family Robertiidae
- PristerodontiaPristerodontiaPristerodontia is a group of dicynodont therapsids that includes cryptodontids, geikiids, lystrosaurids, kannemeyeriids, and other related forms. Pristerodontians were one of the few groups of dicynodonts to survive the Permian-Triassic extinction event, diversifying in the Triassic....
- Family Aulacocephalodontidae
- Family Dicynodontidae
- Family LystrosauridaeLystrosauridaeLystrosauridae was a family of Synapsids from the Permian and Triassic time periods.-Distribution:-Triassic Distribution:In the Triassic period, Lystrosaurids lived in Antarctica and China.-Relatives:...
- Family Oudenodontidae
- Family Pristerodontidae
- Superfamily KannemeyeriiformesKannemeyeriiformesKannemeyeriiformes is a group of Triassic dicynodonts. Four families have been included in the group: Kannemeyeriidae, Shansiiodontidae, Stahleckeriidae, and Dinodontosauridae. Occasionally some of these families are not recognized, with most kannemeyeriiforms being placed in Kannemeyeriidae....
- Family KannemeyeriidaeKannemeyeriidaeKannemeyeriidae is a family of large, stocky, beaked and sometimes tusked dicynodonts. They were the dominant large terrestrial herbivores through most of the Triassic period...
- Family Shansiodontidae
- Family Stahleckeriidae
- Family Kannemeyeriidae
- Anomocephalus
Phylogeny
CladogramCladogram
A cladogram is a diagram used in cladistics which shows ancestral relations between organisms, to represent the evolutionary tree of life. Although traditionally such cladograms were generated largely on the basis of morphological characters, DNA and RNA sequencing data and computational...
modified from Liu et al. (2009):