Pyrotheria is an order of

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

s. These

mastodon A mastodon ( 'breast' + 'tooth') is any proboscidean belonging to the extinct genus ''Mammut'' (family Mammutidae). Mastodons inhabited North and Central America during the late Miocene or late Pliocene up to their extinction at the end of th ...

-like

ungulates Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. These include odd-toed ungulates such as horses, rhinoceroses, and tapirs; and even-toed ungulates such as cattle, pigs, giraffes, cam ...

include the

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

Baguatherium ''Baguatherium'' is an extinct genus of herbivorous mammal, belonging to the order Pyrotheria. It lived during the Early Oligocene, and its fossilized remains were discovered in Peru. Description Although the fossils known are very partial ...

'', ''

Carolozittelia ''Carolozittelia'' is an extinct genus of mammals, belonging to the order Pyrotheria. It contains the single species ''Carolozittelia tapiroides'' which lived during the Early Eocene. Its fossilized remains were found in South America. Descrip ...

'', ''

Colombitherium ''Colombitherium'' is an extinct mammal from Eocene, Late Eocene Colombia. It has originally been assigned to the order Pyrotheria and the family Colombitheriidae, although a later detailed analysis of the fossil questions that classification. A ...

'', ''

Griphodon ''Griphodon'' is an extinct genus of mammals, belonging to the order Pyrotheria. It lived during the Middle Eocene, in what is now Peru. Description All that is known about this animal is a fragment of a mandible complete with teeth. Its tee ...

'', ''

Propyrotherium ''Propyrotherium'' is an extinct genus of mammals, belonging to the order Pyrotheria. It lived during the Late Eocene, in what is now South America. Description This animal is only known from its fossilized dentition. From a comparison with i ...

'', ''

Proticia ''Proticia'' is an extinct genus of mammals belonging to the order Pyrotheria. It lived during the Early Eocene, and its fossilized remains were discovered in South America. Description This animal is only known from a fragmentary mandible pr ...

'', and ''

Pyrotherium ''Pyrotherium'' ('fire beast') is an extinct genus of South American ungulate, of the order Pyrotheria, that lived in what is now Argentina and Bolivia, during the Late Oligocene.digitigrade In terrestrial vertebrates, digitigrade () locomotion is walking or running on the toes (from the Latin ''digitus'', 'finger', and ''gradior'', 'walk'). A digitigrade animal is one that stands or walks with its toes (metatarsals) touching the groun ...

tapir Tapirs ( ) are large, herbivorous mammals belonging to the family Tapiridae. They are similar in shape to a pig, with a short, prehensile nose trunk. Tapirs inhabit jungle and forest regions of South and Central America, with one species inhabit ...

-like mammals with relatively short, slender limbs and five-toed feet with broad, flat

phalanges The phalanges (singular: ''phalanx'' ) are digital bones in the hands and feet of most vertebrates. In primates, the thumbs and big toes have two phalanges while the other digits have three phalanges. The phalanges are classed as long bones. ...

. Their fossils are restricted to

Paleocene The Paleocene, ( ) or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), E ...

through

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...

deposits of

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

and

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

. Some experts place the clade

Xenungulata Xenungulata ("strange ungulates") is an order of extinct and primitive South American hoofed mammals that lived from the Late Paleocene to Early Eocene (Itaboraian to Casamayoran in the SALMA classification). Fossils of the order are known f ...

(which contains several genera, including ''

Carodnia ''Carodnia'' is an extinct genus of South American ungulate known from the Early Eocene of Brazil, Argentina, and Peru. ''Carodnia'' is placed in the order ''Xenungulata'' together with ''Etayoa'' and '' Notoetayoa''. ''Carodnia'' is the larg ...

'') within Pyrotheria, even when dentition, although bilophodont in both orders, is very different. For most scholars, the two orders remain separated. The dentition is complete with strong,

procumbent This page provides a glossary of plant morphology. Botanists and other biologists who study plant morphology use a number of different terms to classify and identify plant organs and parts that can be observed using no more than a handheld magnify ...

chisel A chisel is a tool with a characteristically shaped cutting edge (such that wood chisels have lent part of their name to a particular grind) of blade on its end, for carving or cutting a hard material such as wood, stone, or metal by hand, stru ...

-shaped

incisors Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wh ...

, strong sharp-pointed

canines Canine may refer to: Zoology and anatomy * a dog-like Canid animal in the subfamily Caninae ** ''Canis'', a genus including dogs, wolves, coyotes, and jackals ** Dog, the domestic dog * Canine tooth, in mammalian oral anatomy People with the surn ...

, and low-crowned cheek teeth with

bilophodont The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone to ...

molars. The affinities of the Xenungulata remain uncertain. Affinities with the

Dinocerata Dinocerata (from the Greek (), "terrible", and (), "horn") is an extinct order of plant-eating hoofed mammals with horns and protuberant canine teeth. Classification A 2015 phylogenetic study recovered Dinocerata as closely related to '' ...

are strongly supported by the dental characteristics. Initial study of the structure of the tarsus suggested that the xenungulates had a 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 ("heavy-footed") is an order of extinct mammals known from Asia, Africa and Eastern Europe. Most of the embrithopod genera are known exclusively from jaws and teeth dated from the late Paleocene to the late Eocene; however, the orde ...

. It remains to be seen which of these views will turn out to be right. This means that the Pyrotheria could be members of no less than three major cladistic branches of placental mammals:

Meridiungulata South American native ungulates, commonly abbreviated as SANUs, are extinct ungulate-like mammals of controversial affinities that were indigenous to South America prior to the Great American Biotic Interchange. They comprise five major groups co ...

(if

xenungulates Xenungulata ("strange ungulates") is an order of extinct and primitive South American hoofed mammals that lived from the Late Paleocene to Early Eocene (Itaboraian to Casamayoran in the SALMA classification). Fossils of the order are known f ...

are the closest relatives),

Laurasiatheria Laurasiatheria ("laurasian beasts") is a superorder of placental mammals that groups together true insectivores ( eulipotyphlans), bats ( chiropterans), carnivorans, pangolins ( pholidotes), even-toed ungulates (artiodactyls), odd-toed ungulates ...

(if

dinocerata Dinocerata (from the Greek (), "terrible", and (), "horn") is an extinct order of plant-eating hoofed mammals with horns and protuberant canine teeth. Classification A 2015 phylogenetic study recovered Dinocerata as closely related to '' ...

ns are the closest relatives) and

Afrotheria Afrotheria ( from Latin ''Afro-'' "of Africa" + ''theria'' "wild beast") is a clade of mammals, the living members of which belong to groups that are either currently living in Africa or of African origin: golden moles, elephant shrews (also know ...

(if embrithopods are the closest relatives).

Classification

Colombitheriidae Pyrotheria is an order of extinct meridiungulate mammals. These mastodon-like ungulates include the genera '' Baguatherium'', '' Carolozittelia'', ''Colombitherium'', '' Griphodon'', '' Propyrotherium'', ''Proticia'', and '' Pyrotherium''. ...

**''

'' **''

'' *

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'', '' Griphodon'', '' Pr ...

**''

Pyrotherium ''Pyrotherium'' ('fire beast') is an extinct genus of South American ungulate, of the order Pyrotheria, that lived in what is now Argentina and Bolivia, during the Late Oligocene.Griphodon ''Griphodon'' is an extinct genus of mammals, belonging to the order Pyrotheria. It lived during the Middle Eocene, in what is now Peru. Description All that is known about this animal is a fragment of a mandible complete with teeth. Its tee ...

'' **''

References

{{Taxonbar, from=Q133505 Meridiungulata Paleocene first appearances Oligocene extinctions Fossil taxa described in 1895