The Groves' dwarf lemur was recently discovered on Madagascar. Edward E. Louis, Jr.

As small as the world can seem sometimes, thanks to the internet and social media, it’s inspiring to know that scientists are still discovering new species out there. And we’re not just talking about deep-sea fish and beetles.

In fact, scientists just identified a half dozen new primates, including a Madagascan dwarf lemur, two bug-eyed tarsiers from Indonesia, and two new subspecies of slender lorises hailing from Sri Lanka.

And let’s not forget the Blue Nile patas monkey, a native of Ethiopia and Sudan. This rather cheeky-looking critter has a dark face and a white handlebar mustache. To complete the picture, you’ll have to imagine that mug coming at you at around 34 miles per hour―because patas monkeys are among the fastest ground-running primates on earth.

But as fascinating as it is to learn there are still undiscovered species waiting for us out in the bush, the new finds also come with a troubling caveat. Of the six new primates, experts predict that after more rigorous analysis, five will end up on the International Union for Conservation of Nature’s Red List: the lorises, the tarsiers, and the lemur.

Unfortunately, that’s not surprising. Of the 700 or so primate species and subspecies across the world, about 62 percent are now threatened with extinction, says Anthony Rylands, the newly appointed primate conservation director for Global Wildlife Conservation. Rylands is also the deputy chair of the IUCN/SSC Primate Specialist Group and editor of the journal Primate Conservation, which described all these new animals in its most recent issue.

The lion-tailed macaque of India’s Western Ghats is one primate species that's close to extinction. Arindam Bhattacharya

Why are primates seemingly so predisposed to extinction? Rylands says that almost all of our primate cousins are forest dwellers, and it’s no secret that forests have had a rough go since the beginning of industrialization. Deforestation got particularly bad for primates starting in the 1970s, with the accelerated construction of roads and other infrastructure in the places where they lived, like Brazil and Indonesia.

But here’s the thing. Clear-cutting of rainforest is obviously bad for primates and other animals because it obliterates their habitat, says Rylands. But degradation and fragmentation of habitat can be just as lethal. As forests are carved up, they become less remote and more welcoming to humans. Hunters follow timber and mining crews into the forest, says Rylands, and emerge with enough bush meat to support the commercial market demand. He calls it a double whammy.

“There are now empty forests in some places,” he says. “The forests are still standing but there are no monkeys left.”

In some cases, hunting and consuming primates doesn’t even make sense calorically. Rylands says there are places on the Indonesian island of Sulawesi where eating tarsiers is a Sunday tradition. Mind you, tarsiers are the second-smallest primate in the world. “They’re almost just skin and bone, but they are still hunted, and eaten as snacks,” he says.

The Manado spectral tarsier is one of the smallest primates in the world. Alfrets Masala

The other big problem for primates is traditional medicine. A study published in 2010 found that at least 101 primate species were known to be used in the trade. In Sierra Leone, some people believe children will grow stronger if they wear bracelets made out of chimpanzee bones. In India, macaque blood is thought to cure asthma. And in Bolivia, spider monkey parts are sold as cures for everything from snake and spider bites to sleeping problems and shoulder pain. (Note: There is no scientific evidence for literally any of these claims.)

Add it all up and you’ve got a big ol’ existential mess for humanity’s closest cousins. But even with the deck stacked against them, Rylands believes there’s hope for primates. For starters, every new species we discover—whether leaping through a forest, forgotten in a museum collection, or hiding in the DNA of a previously misidentified animal (as the new Blue Nile patas monkey was)—is a step in the right direction. “You can only save what has a name,” he says. “If it hasn’t got a name, it doesn’t exist.”

And while some may wonder what good it does to split hairs between species and subspecies of loris or tarsier or lemur, these distinctions are important because they illustrate the scope of what we need to preserve. For instance, there are more than 20 species in the Macaca genus, so it’s unlikely the macaque will go extinct anytime soon. But some of those species, like the lion-tailed macaque of India’s Western Ghats, are dangerously close to petering out. And if they do, part of the genus’s genetic diversity that’s essential to its long-term survival goes with them.

“You’re trying to save the evolutionary potential for the survival of primates,” says Rylands.

onEarth provides reporting and analysis about environmental science, policy, and culture. All opinions expressed are those of the authors and do not necessarily reflect the policies or positions of NRDC. Learn more or follow us on Facebook and Twitter.