With a body length of less than 14 inches, silky anteaters are the smallest living anteaters. They're nocturnal, sleeping curled up in a ball during the daytime, sheltered among the trees or tucked within shaded vines, which likely explains why they are among the least-studied xenarthrans, a group of mammals that also includes armadillos and sloths.
Biologist Flávia Miranda of Brazil's Federal University of Minas Gerais has worked with xenarthrans for nearly two decades. In 2005, while participating in an International Union for Conservation of Nature (IUCN) meeting to evaluate the mammals' conservation status, she saw there was little information about the one recognized species of silky anteater, Cyclopes didactylus.
As she began to investigate, she saw that the color of the animals in the northeast of Brazil was different from those in the Amazon.
"Then the hypothesis arose," she tells MNN. "Are we talking about the same species? Are these populations separate for how long? So we started a taxonomic review."
Over a decade and 10 expeditions, Miranda and her colleagues collected DNA samples from 33 wild anteaters, while also examining 287 specimens from 20 natural history collections.
Her instincts were spot on; not only were the two groups different, but it looked like there were as many as seven different species of silky anteaters. Miranda details her findings in a study published in the Zoological Journal of the Linnean Society.
Finding the hard to find
The biggest challenge for the research was finding and catching live animals in order to get samples to test genetics, Miranda says.
"It was very difficult to find an animal that weighs around 250 grams [less than 9 ounces], is nocturnal, that does not vocalize and does not shine eyes in the midst of trees [that are 1/4 mile high] in the Amazon."
The researchers handed out flyers through Brazil's indigenous riverside areas, asking people for their help in finding and catching the silky anteaters. Even after talking to more than 70 local people, it still took two years before they were able to capture their first animal.
Eventually, they were able to find nearly three dozen. They measured them and took blood samples. Using genetic, morphological and morphometric analysis, Miranda says they were able to define seven distinct species.
But finding these tiny, fuzzy creatures doesn't mean they will be around for long.
"We do not have ideas of prevalence, but I believe that a species may already be in danger of extinction," Miranda says.
Cycloes xinguensi is from the Xingu region, which has been greatly impacted by hydropower plant construction and deforestation. The next challenge, Miranda says, is to analyze the species' conservation status with the IUCN.
When asked to explain the appeal of the small, furry animals, Miranda describes her excitement simply:
"They are exclusive animals of Latin America, true living fossils. They have unique anatomical and physiological characteristics," she says. "They are incredible!"