Peltephilidae

Peltephilidae (meaning "armor-liking") is a family of South American cingulates (armadillos) that lived for over 40 million years, but peaked in diversity towards the end of the Oligocene and beginning of the Miocene in what is now Argentina. They were exclusive to South America due to its geographic isolation at the time, one of many of the continent's strange endemic families. Peltephilids are one of the earliest known cingulates, diverging from the rest of Cingulata in the Early Eocene.

== History of research == Fossils of peltephilids were first unearthed in the 1880s by Argentine paleontologist Carlos Ameghino, who had been searching for mammal remains in the Miocene-aged strata of the Santa Cruz Formation in Barrancas del Río Santa Cruz in Santa Cruz, Argentina. The outcrops that were visited had previously been mentioned by Francisco Moreno, who mentioned the discovery of cingulate fossils from the locale in 1882. The material recovered by Ameghino was later described by his brother Florentino, who was one of the most prolific paleontologists of the 19th century. Florentino Ameghino went on to name 11 species of armadillo based on the remains collected by Carlos, including two species of a new genus he dubbed called Peltephilus. The fossils were very fragmentary, consisting purely of unusual, isolated osteoderms (bony "scales" in the skin) that he believed were of a dasypodid. Even more strange osteoderms were found by Carlos in later expeditions to the exposures of the Santa Cruz Formation until, resulting in the discovery of a skull and associated osteoderms from Monte Observacion, which he dubbed Peltephilus ferox. Ameghino noted the strange nature of the skull, inspiring him to create the family Peltephilidae three years later.