The nine-banded armadillo (Dasypus novemcinctus) is actually four different species, including a previously undescribed species endemic to the Guiana Shield, according to new research.
Armadillos are New World placental mammals within the order Cingulata. Along with the anteaters and sloths, they form part of the 100-million-year-old superclade Xenarthra.
The nine-banded armadillo is the most widespread xenarthran species across the Americas.
Recent studies have suggested it is composed of four distinct lineages of uncertain taxonomic status.
“It was widely accepted that the nine-banded armadillo ranges from northern Argentina all the way to southern Illinois, but in recent years, some scientists have been putting forth evidence that this is actually a complex of multiple different species,” said Dr. Frédéric Delsuc, a research director at CNRS.
“By studying the DNA of armadillos from all along this range, we put together a very detailed genomic analysis that makes us very confident that they are actually four species.”
“With the new classification, the armadillo that’s found in the United States should now be called the Mexican long-nosed armadillo,” added Dr. Anderson Feijó, a researcher at the Field Museum.
“Moreover, the new species, the Guianan long-nosed armadillo (Dasypus guianensis), is the first armadillo described in the last 30 years.”
In the study, the researchers sequenced mitochondrial and nuclear genomes of Dasypus armadillos sampled across the entire distribution.
The combination of the genetic data and physical traits led them to the conclusion that the nine-banded armadillo is actually four genetically distinct species.
Accordingly, several subspecies within this species have been elevated to being species in their own right.
The armadillos found in Mexico and the United States, formerly in the subspecies Dasypus novemcinctus mexicanus, are now just Dasypus mexicanus: the Mexican long-nosed armadillo.
The subspecies fenestratus, found in the central part of the range, is now its own species, and the original species name novemcinctus is now restricted to South America.
Meanwhile, the data showed that another branch of the armadillo family tree didn’t belong in any of these three pre-existing groups.
A region of northeastern South America, known as the Guiana Shield, is home to the newest armadillo species: Dasypus guianensis.
The new armadillo is a bit bigger than the other three species, has a hairless shell, a robust, dome-shaped skull, and an additional bone in its spine.
But overall, all four species look very similar to the untrained eye.
“They’re almost impossible to differentiate in the field,” Dr. Delsuc said.
A paper on the findings was published in the journal Systematic Biology.
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Mathilde Barthe et al. Exon capture museomics deciphers the nine-banded armadillo species complex and identifies a new species endemic to the Guiana Shield. Systematic Biology, published online June 22, 2024; doi: 10.1093/sysbio/syae027
Source : Breaking Science News