In a water tank at a campground in northeastern India, a “large”-headed creature floated along the surface. Passing scientists peered into the tank and spotted the “cryptic” animal.

It turned out to be a new species.

Researchers visited the Tale Wildlife Sanctuary in Arunachal Pradesh in 2015 to survey wildlife, according to a study published in the journal Records of the Zoological Survey of India and shared with McClatchy News on July 4. The area was a known biodiversity hotspot.

During their visit, researchers found a frog in a water tank near a campground, the study said. They captured the animal and initially identified it as the country’s first record of the Maoson horned frog.

But something about that identification didn’t quite add up. Maoson horned frogs live in Vietnam and China, but this frog was found 1,000 miles away in Arunachal Pradesh, the study said. So how did it get there?

Researchers decided to take another look at the “cryptic” frog and tested its DNA. Based on these results, they realized they’d discovered a new species: Xenophrys apatani, or the Apatani horned frog.

The Apatani horned frog is considered “medium-sized,” reaching just over 2 inches in length, the study said. It has a “large” head, “pointed” snout and “rounded” tongue.

A photo shows the frog’s dark greenish-brown coloring. Its back and sides have a scattering of lighter brown blotches.

Researchers said they named the new species after the Apatani, a tribal group living in the area where the species was discovered, because of their “ingenuity in conservation of wild flora and fauna.”

So far, the Apatani horned frog has only been found at the Tale Wildlife Sanctuary in Arunachal Pradesh, the study said. The Lower Subansiri District Government shared photos of this park, also known as the Talley Valley Wildlife Sanctuary.

Arunachal Pradesh is a disputed region in the Himalayan mountains along the India-China border. Although India controls the region, both India and China claim it. The region is about 1,300 miles east of New Delhi and about 3,200 miles southwest of Shanghai.

The new species was identified by its body shape, coloring and other subtle physical features, the study said. DNA analysis found the new species had at least 4% genetic divergence from other related frog species.

The research team included Bhaskar Saikia, Bikramjit Sinha, A. Shabnam, Ilona Jacinta Kharkongor and K.P. Dinesh.