Cingulata, part of the superorder

Xenarthra Xenarthra (; from Ancient Greek ξένος, xénos, "foreign, alien" + ἄρθρον, árthron, "joint") is a superorder and major clade of placental mammals native to the Americas. There are 31 living species: the anteaters, tree sloths, and ...

, is an

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

of armored

New World The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas, and sometimes Oceania."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: ...

placental Placental mammals (infraclass Placentalia ) are one of the three extant subdivisions of the class Mammalia, the other two being Monotremata and Marsupialia. Placentalia contains the vast majority of extant mammals, which are partly distinguished ...

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

s. The

armadillo Armadillos () are New World placental mammals in the order (biology), order Cingulata. They form part of the superorder Xenarthra, along with the anteaters and sloths. 21 extant species of armadillo have been described, some of which are dis ...

s, whose species are split between the families Dasypodidae and Chlamyphoridae, are the only surviving members of the order. Two groups of cingulates much larger than extant armadillos (maximum body mass of 45 kg (100 lb) in the case of the giant armadillo) existed until recently: pampatheriids, which reached weights of up to 200 kg (440 lb) and chlamyphorid

glyptodont Glyptodonts are an extinct clade of large, heavily armoured armadillos, reaching up to in height, and maximum body masses of around 2 tonnes. They had short, deep skulls, a fused vertebral column, and a large bony carapace made up of hundreds o ...

s, which attained masses of 2,000 kg (4,400 lb) or more. The cingulate order originated in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

during the Paleocene epoch about 66 to 56 million years ago, and due to the continent's former isolation remained confined to it during most of the

Cenozoic The Cenozoic Era ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterized by the dominance of mammals, insects, birds and angiosperms (flowering plants). It is the latest of three g ...

. However, the formation of a

land bridge In biogeography, a land bridge is an isthmus or wider land connection between otherwise separate areas, over which animals and plants are able to cross and colonize new lands. A land bridge can be created by marine regression, in which sea le ...

allowed members of all three families to migrate to southern North America during the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58 or early

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

as part of the

Great American Interchange The Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which land ...

. After surviving for tens of millions of years, all of the pampatheriids and giant

s apparently died out during the

Quaternary extinction event The Late Pleistocene to the beginning of the Holocene saw the extinction of the majority of the world's megafauna, typically defined as animal species having body masses over , which resulted in a collapse in faunal density and diversity acro ...

at the beginning of the

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

, along with much of the rest of the regional

megafauna In zoology, megafauna (from Ancient Greek, Greek μέγας ''megas'' "large" and Neo-Latin ''fauna'' "animal life") are large animals. The precise definition of the term varies widely, though a common threshold is approximately , this lower en ...

, shortly after the colonization of the Americas by

Paleo-Indians Paleo-Indians were the first peoples who entered and subsequently inhabited the Americas towards the end of the Late Pleistocene period. The prefix ''paleo-'' comes from . The term ''Paleo-Indians'' applies specifically to the lithic period in ...

Description

Armadillos have dorsal armor that is formed by

osteoderm Osteoderms are bony deposits forming scales, plates, or other structures based in the dermis. Osteoderms are found in many groups of extant and extinct reptiles and amphibians, including lizards, crocodilians, frogs, temnospondyls (extinct amph ...

s, plates of dermal bone covered in relatively small, overlapping

keratin Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. It is the key structural material making up Scale (anatomy), scales, hair, Nail (anatomy), nails, feathers, horn (anatomy), horns, claws, Hoof, hoove ...

ized epidermal scales called "

scute A scute () or scutum (Latin: ''scutum''; plural: ''scuta'' "Scutum (shield), shield") is a bony external plate or scale overlaid with horn, as on the shell of a turtle, the skin of crocodilians, and the feet of Bird anatomy#Scales, birds. The ter ...

s". Most species have rigid shields over the shoulders and hips, with three to nine bands separated by flexible skin covering the back and flanks. Pampatheres also had shells that were flexible due to three movable lateral bands of osteoderms. The osteoderms of pampatheres were each covered by a single scute, unlike those of armadillos, which have more than one. Glyptodonts, on the other hand, had rigid, turtle-like shells of fused osteoderms. Both groups have or had a cap of armor atop their heads. Glyptodonts also had heavily armored tails; some, such as '' Doedicurus'', had mace-like clubs at the ends of their tails, similar to those of

ankylosaur Ankylosauria is a group of herbivorous dinosaurs of the clade Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful l ...

s, evidently used for defensive or agonistic purposes. Most armadillos eat insects and other invertebrates; some are more

omnivorous An omnivore () is an animal that regularly consumes significant quantities of both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize ...

and may also eat small vertebrates and vegetable matter. Pampatheres are thought to have been specialized for

grazing In agriculture, grazing is a method of animal husbandry whereby domestic livestock are allowed outdoors to free range (roam around) and consume wild vegetations in order to feed conversion ratio, convert the otherwise indigestible (by human diges ...

, and isotopic analysis indicates the diet of glyptodonts was dominated by C4

grass Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and spe ...

es. Euphractinae is unique for speciations towards

carnivory A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose nutrition and energy requirements are met by consumption of animal tissues (mainly mu ...

, culminating in the macropredatory genus ''

Macroeuphractus ''Macroeuphractus'' is a genus of extinct armadillos from the Late Miocene to Late Pliocene of South America. The genus is noted for its large size, with ''Macroeuphractus outesi'' being the largest non- pampathere or glyptodont armadillo discove ...

''.

Classification

The taxonomic table below follows the results of a

phylogenetic analysis In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical data ...

published by Delsuc ''et al.'', 2016. While glyptodonts have traditionally been considered stem-group cingulates outside the group that contains modern armadillos, this 2016 study conducted an analysis of '' Doedicurus''

mtDNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in ...

and found that it was, in fact, nested within the modern armadillos as the

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

of a

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

consisting of Chlamyphorinae and Tolypeutinae. Order Cingulata * Family † Peltephilidae Ameghino 1894 ** Genus †'' Anantiosodon'' Ameghino 1891 ** Genus †'' Epipeltephilus'' Ameghino 1904 ** Genus †'' Parapeltecoelus'' Bordas 1938 ** Genus †'' Peltecoelus'' Ameghino 1902 ** Genus †'' Peltephilus'' Ameghino 1887 (Horned armadillo) ** Genus †'' Ronwolffia'' Shockey 2017 * Family † Paleopeltidae Ameghino 1895 ** Genus †'' Palaeopeltis'' Ameghino 1895 * Family † Pampatheriidae ** Genus ? †'' Machlydotherium'' Ameghino 1902 ** Genus †'' Holmesina'' Simpson 1930 ** Genus †'' Kraglievichia'' Castellanos 1927 ** Genus †'' Machlydotherium'' ** Genus †'' Pampatherium'' Ameghino 1875 ex Gervais & Ameghino 1880 ** Genus †'' Scirrotherium'' Edmund & Theodor 1997 ** Genus †'' Tonnicinctus'' Góis et al. 2015 ** Genus †'' Vassallia'' Castellanos 1927 'Plaina'' Castellanos 1937">Plaina.html" ;"title="'Plaina">'Plaina'' Castellanos 1937** Genus †''Yuruatherium'' Ciancio et al. 2012 * Family †Pachyarmatheriidae Fernicola et al. 2018 ** Genus †'' Neoglyptatelus'' Carlini, Vizcaíno & Scillato-Yané 1997 ** Genus †'' Pachyarmatherium'' Downing & White 1995 * Family Dasypodidae (long-nosed armadillos) ** Genus †'' Acantharodeia'' ** Genus †'' Amblytatus'' ** Genus †'' Archaeutatus'' ** Genus †'' Astegotherium'' ** Genus †'' Barrancatatus'' ** Genus †'' Chasicotatus'' ** Genus †''

Chorobates The chorobates, described by Vitruvius in Book VIII of the ''De architectura'', was used to measure horizontal planes and was especially important in the construction of Aqueduct (bridge), aqueducts. Similar to modern spirit levels, the choroba ...

'' ** Genus †'' Coelutaetus'' ** Genus †'' Eocoleophorus'' ** Genus †'' Epipeltecoelus'' ** Genus †'' Eutatus'' ** Genus †'' Hemiutaetus'' ** Genus †'' Isutaetus'' ** Genus †'' Lumbreratherium'' ** Genus †'' Macrochorobates'' ** Genus †'' Mazzoniphractus'' ** Genus †'' Meteutatus'' ** Genus †'' Pedrolypeutes'' ** Genus †'' Prodasypus'' ** Genus †'' Proeutatus'' ** Genus †'' Prostegotherium'' ** Genus †'' Pucatherium'' ** Genus †'' Punatherium'' ** Genus †'' Stegotherium'' ** Genus †'' Stenotatus'' ** Genus †'' Utaetus'' ** Genus †'' Vetelia'' ** Subfamily Dasypodinae *** Genus †'' Anadasypus'' *** Genus ''

Dasypus ''Dasypus'' is the only extant genus in the family Dasypodidae. Its species are known as long-nosed or naked-tailed armadillos. They are found in South America, South, Central America, Central, and North America, as well as on the Caribbean islan ...

'' *** Genus †'' Nanoastegotherium'' *** Genus †'' Parastegosimpsonia'' *** Genus †'' Pliodasypus'' *** Genus †'' Propraopus'' *** Genus †'' Riostegotherium'' *** Genus †'' Stegosimpsonia'' * Family Chlamyphoridae: glyptodonts and other armadillos ** Subfamily Chlamyphorinae: fairy armadillos *** Genus '' Calyptophractus'' *** Genus '' Chlamyphorus'' ** Subfamily Euphractinae: hairy, six-banded and pichi armadillos *** Genus '' Chaetophractus'' *** Genus †'' Doellotatus'' *** Genus '' Euphractus'' *** Genus †''

'' ***Genus †'' Peltephilus'' *** Genus †'' Proeuphractus'' *** Genus †'' Paleuphractus'' *** Genus '' Zaedyus'' ** Subfamily † Glyptodontinae: glyptodonts *** Genus †'' Doedicurus'' *** Genus †'' Glyptodon'' *** Genus †'' Glyptotherium'' *** Genus †'' Hoplophorus'' *** Genus †'' Panochthus'' *** Genus †''

Parapropalaehoplophorus ''Parapropalaehoplophorus'' is an Extinction, extinct genus of comparatively small (compared to ''Glyptodon'') species of glyptodont, extinct relatives of the modern armadillo. The sole species, ''P. septentrionalis'', identified in 2007 from the ...

'' *** Genus †''

Plaxhaplous ''Plaxhaplous'' was a genus of glyptodont, an extinct relative of the modern armadillo. It lived in the Pleistocene epoch. The type species is ''Plaxhaplous canaliculatus''. ''Plaxhaplous canaliculatus'' fossils were found in Argentina, near Luj ...

'' ** Subfamily

Tolypeutinae Tolypeutinae is a subfamily of armadillos in the family Chlamyphoridae, consisting of the giant, three-banded and naked-tailed armadillos. __TOC__ Taxonomy It contains the following genera: *'' Cabassous'' *'' Kuntinaru'' *'' Priodontes'' *' ...

: giant, three-banded and naked-tailed armadillos *** Genus ''

Cabassous ''Cabassous'' is a genus of South and Central American armadillos. The name is the Latinised form of the Carib language, Kalini word for "armadillo". Cladogram of living ''Cabassous'' The genus contains the following four species: Reference ...

'' *** Genus †'' Kuntinaru'' *** Genus '' Priodontes'' *** Genus ''

Tolypeutes The genus ''Tolypeutes'' contains the two species of three-banded armadillos. They are restricted to open and semi-open habitats in South America. Of the several armadillo genera, only ''Tolypeutes'' rely heavily on their armor for protection. W ...

References

{{Taxonbar, from=Q1242326 Xenarthra Mammal orders Taxa named by Johann Karl Wilhelm Illiger Extant Thanetian first appearances