Courtesy Conservation International
Red-eyed tree frog: A team of scientists visited an archeological site in Honduras' Mosquitia rainforest. While there, they spotted several rare animals. The red-eyed tree frog was one of 22 amphibian species documented.
Courtesy Conservation International
Lush vegetation: Expedition leader Trond Larsen tells CNN Travel that it's a beautiful spot: "a very lush forest, crystal-clear stream cascades; it's extremely picturesque."
Courtesy Conservation International
Great curassow: The scientists decided to visit following the recent rediscovery of the ruins, in 2012: "The impetus for this expedition was really driven by the fact that these amazing archaeological discoveries were made at this site not too many years ago," says Larsen.
Courtesy Conservation International
Rare occurrence: Larsen and his team witnessed an ornate hawk-eagle prey upon an endangered great green macaw.
Courtesy Conservation International
Mexican climbing salamander: The Bolitoglossa mexicana salamander is often spotted in North America -- but it's less commonly found in the Neotropics.
Courtesy Conservation International
Water crabs: In the beautiful streams, water crabs were spotted. The team says they provide important food for many animals, including the endangered Neotropical river otter.
Courtesy Conservation International
Coral tree snake: The false tree coral snake was thought to be extinct in Honduras -- until it was rediscovered on this expedition.
Courtesy Conservation International
Jaguar: The team took this shot of a jaguar at Ciudad Blanca. Jaguars in the area have fallen victim to deforestation, habitat loss and overhunting.
Courtesy Conservation International
Rediscovered species: The tiger beetle was thought to be virtually extinct -- it had previously been recorded at a single site in Nicaragua. The beetle was rediscovered during the expedition.
Courtesy Conservation International
Pale-faced bat: The team also spotted the pale-faced bat, last documented in Honduras in 1942.
Courtesy Conservation International
Worm salamander: On the scientific expedition, team members spotted a species of worm salamander. It's high on the list of conservation priorities as it's very vulnerable.
Courtesy Conservation International
Male Harlequin beetle: Larsen says he particularly enjoys admiring insects and beetles: "I'm fascinated with the smaller creatures that represent so much of the biodiversity around us," he says.
Courtesy Conservation International
Adventurers: The team from Conservation International's Rapid Assessment Program (RAP) on site in Honduras.
Courtesy Conservation International
White-lipped peccaries: "What I was most surprised about was the high abundance of white-lipped peccaries," says Larsen. "They need such huge areas and move across [such] wide landscapes to survive that we did not expect to find them there."
Courtesy Conservation International
Glass frog: During the expedition, the team also saw a glass frog.
Courtesy Conservation International
Morpho butterfly: The team took this incredible shot of a morpho helenor butterfly -- one of the largest butterflies in the world, with wings spanning from five to eight inches.
Courtesy Conservation International
Living in nature: The team slept in tents and hammocks in the forest. "I like to get right in there, get down in the dirt, get in the water, search everywhere for as much as we can find," says Larsen.
Courtesy Conservation International
Puma: Larsen also had an unexpected encounter with a puma. "I was on a night walk by myself in a very small tight narrow ravine and turned around and my head lamp illuminated these big glowing eyes," he recalls.
Courtesy Conservation International
Baird's tapir: Also known as the Central American tapir, this endangered species is native to Mexico, Central America and northwestern South America.
Courtesy Conservation International
Eyelash viper: The region is home to some venomous snakes, including the eyelash viper, which uses its tongue to smell its surroundings.
CNN  — 

Deep in the lush greenery of the Mosquitia rainforest in Honduras, bordered by steep ridges, lies an archeological site home to ancient ruins and an apparently thriving ecosystem.

There’s long been a rumor of a pre-Columbian settlement in this region, sometimes known as the “Lost City of the Monkey God” or “La Ciudad Blanca.”

Aviator Charles Lindbergh said he saw it from the sky when he was flying over the region in the 1920s – and many explorers have tried and failed to track down the legendary spot in Central America.

In 2015, an archaeological site was discovered in the area and is believed by some to be the settlement that inspired the legend.

Now a team of scientists, led by Conservation International’s Rapid Assessment Program (RAP) in coordination with the Government of Honduras, have discovered this site is home to rare species.

Creatures uncovered include a tiger beetle, previously only ever recorded in Nicaragua and believed to be extinct.

The government of Honduras wanted to know what wildlife was living in this undisturbed region and commissioned this extensive survey of the area’s biodiversity, with incredible results.

Overall, the team recorded 246 species of butterflies and moths, 30 bats, 57 amphibians and reptiles, alongside many plants, fishes, mammals and insects.

Many of these are rare and endangered.

Beautiful spot

Courtesy Conservation International
The team had to be helicoptered into this remote rainforest area.

But first, the team had to get to this secluded spot.

“It’s so exciting to get to visit places where literally there’s so few ways to get there,” Trond Larsen, director of Conservation International’s rapid assessment program, tells CNN Travel.

“There’s no roads, there’s no logistical infrastructure to access, so you have to helicopter in. And when you do that, you end up visiting places where wildlife tends to be much more abundant.”

Courtesy Conservation International
The venomous eyelash viper.

Larsen says the animals and creatures that live in the area aren’t used to human interaction, which allowed for some incredible moments of interaction and education.

“Large groups of monkeys, for example, hang out and try to figure out what you are and what’s going on, there’s an opportunity to see tremendous amounts of wildlife,” he says.

The explorer also highlights the beauty and serenity of the area.

“There’s big, old-growth trees that you often just don’t see in places that are more impacted by people. So these massive trees that are hundreds or even thousands of years old, that are just overwhelming in size, it’s amazing to see.”

Courtesy Conservation International
A species of worm salamander.

Is this a new type of jellyfish in the Indian Ocean?

The archaeological excavations in the region are still ongoing.

For Larsen, spotting rare and endangered creatures is just as exciting.

“The most exciting finds were probably the rediscoveries of these species that [were] thought to be extinct in Honduras for a long time,” he says.

The explorer was most surprised to see the white-lipped peccaries – a species distantly related to pigs.

“They need such huge areas and move across wide landscapes to survive that we did not expect to find them there, but it was a really good indicator of this intact ecosystem,” he says.

Incredible pictures capture rare 'Elephant Queen' in Kenya

Amazing photographs

Courtesy Conservation International
The team took this amazing shot of a glass frog.

While exploring the area – sleeping in tents and hammocks deep in the verdant forest – Larsen, who also took photographs on the expedition, enjoyed getting as close as possible to the local wildlife.

“I like to get right in there, get down in the dirt, get in the water, search everywhere for as much as we can find,” he says.

One particular encounter was unexpected, but memorable.

“I was on a night walk by myself in a very small tight narrow ravine and turned around and my head lamp illuminated these big glowing eyes – and I didn’t know what it was at first. And they came very close to me and I realized it was a big puma.”

Courtesy Conservation International
A morpho helenor butterfly in the rainforest.

Colombia's 'Lost City' is older than Machu Picchu, and hardly anyone visits

Larsen took a range of photographs – from micro images capturing the animals in all their detail, to wide-lens images that evoke the landscape and the creatures’ home.

“It’s a balance, because I’m a scientist, I’m also collecting data and information on these trips, as one of the biologists participating, but I also carry my camera equipment with me everywhere, and try to photo-document a lot of what we’re seeing,” he says.

Courtesy Conservation International
The team recorded sightings of the pale-faced bat, last documented in Honduras over 70 years ago.

Larsen hopes viewers of the photographs will be left inspired to reflect on the magnificence of our world’s wildlife.

“But being able to see up close what you can find in some of these remote rugged parts of the world, I think really can affect people deeply, especially young people and people who haven’t had a chance to explore so much around the world,” he says.

“But also, the fact that this is in conjunction with these amazing archaeological discoveries, I think it’s extra-exciting. This makes this place truly special.”