|
Cingulata, part of the superorder Xenarthra, is an order of armored New World placental mammals. Dasypodids, the armadillos, are the only surviving family in the order. Two additional families of cingulates much larger than armadillos (maximum body mass of in the case of the giant armadillo〔(Giant Armadillo ''Priodontes maximus'' (Kerr, 1792) ). FaunaParaguay.com〕) existed until recently: pampatheres, which reached weights of up to and glyptodonts, which attained masses of or more. The order originated in South America during the Paleocene epoch, and due to the continent's former isolation remained confined to it during most of the Cenozoic. However, the formation of a land bridge allowed members of all three families to migrate to southern North America during the Pliocene or early Pleistocene as part of the Great American Interchange. After surviving for tens of millions of years, both of the larger families apparently died out during the Quaternary extinction event at the beginning of the Holocene, along with much of the rest of the regional megafauna, shortly after the colonization of the Americas by Paleo-Indians. ==Description== Armadillos have dorsal armor that is formed by osteoderms, plates of dermal bone covered in relatively small, overlapping keratinized epidermal scales called "scutes". 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. All three 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 ankylosaurs, evidently used for defensive or agonistic purposes.〔 Most armadillos eat insects and other invertebrates; some are more omnivorous and may also eat small vertebrates and vegetable matter. Pampatheres are thought to have been specialized for grazing,〔 and isotopic analysis indicates the diet of glyptodonts was dominated by C4 grasses. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「cingulata」の詳細全文を読む スポンサード リンク
|