A new species of armadillo fossil unearthed in Brazil

Paleontologists identify new species of extinct armadillo Partetus From fossilized bone embryos collected in the state of Paraná in southern Brazil.

Hypothetical artistic reconstruction Partetus Oliveirai Middle to late Eocene of Brazil. Image credit: Marcio L. Castro.

Partetus Oliveirai It lived in South America from 42 million years ago to 39 million years ago (mid-late Eocene).

The ancient species belongs to Euphractinae group of armadillo family Dasipidae.

Paleontologist Tabata Klimek of Santa Federal University and his colleagues said, “The armadillo family is represented by modern armadillos and extinct armadillos.''

“This group is stratigraphically and geographically widespread, from southern Patagonia to southern North America.”

“The paleontological record of armadillos is represented primarily by osteoderms.”

“According to other interpretations, they are known from nearly all South American mammal faunas from the late Paleocene/early Eocene, or only from the early Eocene.”

“Euphractinae is the most diverse clade (subfamily) of Dasypodidae,” they noted.

“The earliest undisputed occurrences of euphractin date back to the mid-to-late Eocene of the Gran Barranca region of Argentine Patagonia and the mid-Eocene Upper Lumbrella Formation of northwestern Argentina.”

Partetus “It is one of the earliest branching euphractins,” they added.

“The genus was described in 1902 and the type species is Partetus chicoensis I'm from Patagonia, Argentina. ”

8 bone embryo fossils Partetus Oliveirai It was discovered in the Guavirotuba Formation in Curitiba, Paraná, Brazil.

“The Guavilotuba Formation is the main lithostratigraphic unit of the Curitiba sedimentary basin,” the paleontologists said.

“It is represented by distributed fluvial system deposits consisting of immature subalcoholic sand and mud interspersed with limited gravel deposits at the edges of the basin.”

“Geological features indicate a semi-arid environment, with temporary rivers forming during the rainy season, transporting sediment and forming alluvial fans.”

This new species expands our knowledge of the diversity of armadillos, which lived in southeastern South America during the Paleogene period.

Partetus OliveiraiThe osteoderm differs from other species of this genus in the following ways: (i) More surface glandular and ciliary pores. (ii) flat surface joint areas between osteoderms; There is no groove in the central part of the osteoderm. (iii) large size,” the researchers said.

“Combined, this set of traits does not exist in any other species. Partetus Genus. ”

“The increase in the number and size of surface glandular and ciliary pores may be related to the global cooling that occurred during the mid-to-late Eocene, which affected South American faunas. .”

“Finally, this new species expands our knowledge of the lesser-known diversity of mammals that lived in southeastern South America during the Eocene.”

of findings Published in Journal of Vertebrate Paleontology.

_____

TDF Klimek others. 2024. Uncovering the diversity of Paleogene zonal fauna from Brazil: new species Partetus (Euphractinae) Guavilotuba Formation (Middle to Late Eocene). Journal of Vertebrate Paleontology 44 (1): e2403581;doi: 10.1080/02724634.2024.2403581

Source: www.sci.news

Scientists discover unknown species of armadillo

of Cricket Armadillo (Dasypus novemucinctus) There are actually four different species, including a previously undescribed endemic species. Guiana ShieldAccording to a new study.



Guiana Navajo Armadillo (Dasypus guianensisImage courtesy of Quentin Martinez, https://quentinmartinez.fr.

Armadillos are New World placental mammals. CingulataAlong with anteaters and sloths, they form part of a superclade that dates back 100 million years ago. Xenomorphs.

The cricket armadillo The most widely distributed xenarthropod species Across the Americas.

Recent studies suggest that it consists of four distinct lineages whose taxonomic status is unclear.

“It has been widely believed that the cricket armadillo ranges from northern Argentina to southern Illinois, but in recent years some scientists have presented evidence that it is in fact a complex of several different species,” said Dr. Frédéric Delschuk, research director at the CNRS.

“By studying the DNA of armadillos across their range, we were able to perform a very detailed genomic analysis and become convinced that there are in fact four different species of armadillos.”

“Under the new classification, armadillos found in the United States should be called Mexican long-legged armadillos,” added Dr Anderson Feijo, a researcher at the Field Museum.

“In addition, a new species of Guiana Navajo armadillo (Dasypus guianensis) is the first armadillo described in the past 30 years.

In this study, the researchers analyzed the mitochondrial and nuclear genomes. Dasypus Armadillos were sampled throughout their range.

A combination of genetic data and physical characteristics led them to conclude that cricket armadillos are actually four genetically distinct species.

Thus, some subspecies within this species have come to be recognized as species in their own right.

The armadillo found in Mexico and the United States was formerly a subspecies of Mexican wolfnow just Mexican wolf: Mexican long-legged armadillo.

Subspecies Window StratusThe species that inhabits the central part of its range is now a distinct species, and its original name was Novemucinctas Currently limited to South America.

Meanwhile, the data showed that another branch of the armadillo phylogenetic tree did not belong to any of these three existing groups.

The area of ​​northeastern South America known as the Guiana Shield is home to the newest armadillo species. Dasypus guianensis.

The new armadillo is slightly larger than the other three species, has a hairless shell, a robust domed skull and additional bones in its spine.

Overall, however, to the untrained eye, these four species appear very similar.

“It's nearly impossible to tell in the field,” Dr Delsac said.

a paper The findings were published in the journal. Systematic biology.

_____

Mathilde Barthes othersExon capture museomics deciphers a cricket armadillo species complex and identifies a new species endemic to the Guiana Shield. Systematic biologyPublished online June 22, 2024, doi: 10.1093/sysbio/syae027

Source: www.sci.news