Pyrotheria
Encyclopedia
Pyrotheria is an order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 of extinct meridiungulate
Meridiungulata
Meridiungulata is an extinct clade with the rank of cohort or super-order, containing the South-American ungulates: Pyrotheria , Astrapotheria, Notoungulata and Litopterna...

 mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...

s. These mastodon
Mastodon
Mastodons were large tusked mammal species of the extinct genus Mammut which inhabited Asia, Africa, Europe, North America and Central America from the Oligocene through Pleistocene, 33.9 mya to 11,000 years ago. The American mastodon is the most recent and best known species of the group...

-like ungulates include the genera
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Baguatherium, Carolozittelia, Colombitherium, Gryphodon, Propyrotherium, Proticia, and Pyrotherium
Pyrotherium
Pyrotherium is an extinct genus of South American ungulate, of the order Pyrotheria, that lived in what is now Argentina, during the Early Oligocene...

.

They had the appearance of large, digitigrade
Digitigrade
A digitigrade is an animal that stands or walks on its digits, or toes. Digitigrades include walking birds , cats, dogs, and many other mammals, but not plantigrades or unguligrades...

, tapir
Tapir
A Tapir is a large browsing mammal, similar in shape to a pig, with a short, prehensile snout. Tapirs inhabit jungle and forest regions of South America, Central America, and Southeast Asia. There are four species of Tapirs: the Brazilian Tapir, the Malayan Tapir, Baird's Tapir and the Mountain...

like mammals with relatively short, slender limbs and five-toed feet with broad, flat phalanges. Their fossils are restricted to Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...

 through Oligocene
Oligocene
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...

 deposits of Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

, Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

 and Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

.

Xenungulata

Some experts place the clade Xenungulata, containing the monospecific genus Carodnia
Carodnia
Carodnia vieirai is an extinct meridiungulate mammal from the Paleocene of South America. It is related to, and possibly gave rise to the order Pyrotheria, into which some experts also place Carodnia....

 within Pyrotheria. The dentition is complete with strong, procumbent, chisel
Chisel
A chisel is a tool with a characteristically shaped cutting edge of blade on its end, for carving or cutting a hard material such as wood, stone, or metal. The handle and blade of some types of chisel are made of metal or wood with a sharp edge in it.In use, the chisel is forced into the material...

-shaped incisors, strong sharp-pointed canines
Canine tooth
In mammalian oral anatomy, the canine teeth, also called cuspids, dogteeth, fangs, or eye teeth, are relatively long, pointed teeth...

, and low-crowned cheek teeth with bilophodont molars. The affinities of the Xenungulata remain uncertain. Affinities with the Dinocerata
Dinocerata
Dinocerata mammals are an extinct order of plant-eating, rhinoceros-like hoofed creatures famous for their paired horns and tusk-like canine teeth...

 are strongly supported by the dental
Dentistry
Dentistry is the branch of medicine that is involved in the study, diagnosis, prevention, and treatment of diseases, disorders and conditions of the oral cavity, maxillofacial area and the adjacent and associated structures and their impact on the human body. Dentistry is widely considered...

 characteristics. Initial study of the structure of the tarsus
Tarsus (skeleton)
In tetrapods, the tarsus is a cluster of articulating bones in each foot situated between the lower end of tibia and fibula of the lower leg and the metatarsus. In the foot the tarsus articulates with the bones of the metatarsus, which in turn articulate with the bones of the individual toes...

 suggested that the xenungulates had common ancestry with typical pyrotheres such as Pyrotherium, but a more recent examination of the tarsus of Pyrotherium failed to support this, instead showing some traits shared by Pyrotherium and the Embrithopoda
Embrithopoda
Embrithopoda is an extinct order of mammals which first appeared in the fossil record during the late Eocene and then died out during the Oligocene....

. It remains to be seen which of these views will turn out to be right. This means that the Pyrotheria can be members of no less than three major cladistic branches of placential mammals: Meridiungulata
Meridiungulata
Meridiungulata is an extinct clade with the rank of cohort or super-order, containing the South-American ungulates: Pyrotheria , Astrapotheria, Notoungulata and Litopterna...

 (if xenungulates are the closest relatives), Laurasiatheria
Laurasiatheria
Laurasiatheria is a large group of placental mammals believed to have originated on the northern supercontinent of Laurasia. It includes shrews, hedgehogs, pangolins, bats, whales, most hoofed mammals, and carnivorans, among others....

 (if dinocerata
Dinocerata
Dinocerata mammals are an extinct order of plant-eating, rhinoceros-like hoofed creatures famous for their paired horns and tusk-like canine teeth...

ns are the closest relatives) and Afrotheria
Afrotheria
Afrotheria is a clade of mammals, the living members of which belong to groups from Africa or of African origin: golden moles, sengis , tenrecs, aardvarks, hyraxes, elephants and sea cows. The common ancestry of these animals was not recognized until the late 1990s...

 (if embrithopods
Embrithopoda
Embrithopoda is an extinct order of mammals which first appeared in the fossil record during the late Eocene and then died out during the Oligocene....

 are the closest relatives).

Classification (including Xenungulata)

  • Carodniidae
    • Carodnia
      Carodnia
      Carodnia vieirai is an extinct meridiungulate mammal from the Paleocene of South America. It is related to, and possibly gave rise to the order Pyrotheria, into which some experts also place Carodnia....

  • Colombitheriidae
    • Proticia
    • Colombitherium
  • Pyrotheriidae
    Pyrotheriidae
    Pyrotheriidae is the only family in the order Pyrotheria, provided one does not include the Paleocene genus, Carodnia. These extinct, mastodon-like ungulates include the genera Baguatherium, Carolozittelia, Colombitherium, Gryphodon, Propyrotherium, Proticia, and Pyrotherium.-References:**...

    • Pyrotherium
      Pyrotherium
      Pyrotherium is an extinct genus of South American ungulate, of the order Pyrotheria, that lived in what is now Argentina, during the Early Oligocene...

    • Griphodon
    • Propyrotherium
    • Carolozittelia
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