‘Skittish’ creature found lurking in rocky caves of Thailand. It’s a new species

As darkness fell across a cave in northern Thailand, a “skittish” creature emerged from hiding and ventured into the night.

Visiting scientists caught sight of the “long”-tailed animal — and discovered a new species.

Researchers visited the rocky caves around Pha Mi Village in March 2023 as part of a wildlife survey, according to a study published May 30 in the peer-reviewed journal ZooKeys. The area’s biodiversity had not been well-explored or documented.

During the nighttime survey, researchers found 15 “skittish” geckos living around the rock formations, the study said. They took a closer look at the animals and realized they’d discovered a new species: Cyrtodactylus phamiensis, or the Pha Mi bent-toed gecko.

Pha Mi bent-toed geckos are about 5.8 inches in length, the study said. They have “flattened” heads, spiky bodies and “long” tails that are often missing or regrown. Their “large” eyes are “reddish gold with thin black reticulations.”

A photo shows the tan coloring of a male Pha Mi bent-toed gecko. The lizard has several darker brown bands running across its back and a few white patches on its tail. Its head has a slight yellow hue.

Females of the new species have a similar coloring as males but can vary slightly in pattern, the study said. A baby Pha Mi bent-toed gecko, however, has a bright yellow head, pinkish tones on its upper body and a lighter colored tail, a photo shows.

Pha Mi bent-toed geckos are nocturnal, living in and around rocky caves, the study said. Baby geckos tended to be outside and further away from the cave than adults. Researchers suspect “this may be a way to avoid predation by adults as well as a means to disperse to other karst habitats.”

Researchers described Pha Mi bent-toed geckos as having a “skittish nature” and tendency not to “stray far from their shelters.” This behavior might stem from the presence of several nearby predators, including larger geckos and pit vipers, the study said.

Researchers said they named the new species after the Pha Mi Village where it was discovered and, so far, the only area where it has been found. This village is in the “extreme” north of Thailand and near the border with Myanmar.

The new species likely lives throughout the rock formations in Pha Mi Village area, the study said.

The new species was identified by its distribution, coloring, scale pattern and other subtle physical features, the study said. DNA analysis found the new species had a “large” genetic divergence of at least 13% from other related geckos.

The research team included L. Lee Grismer, Anchalee Aowphol, Jesse Grismer, Akrachai Aksornneam, Evan Quah, Matthew Murdoch, Jeren Gregory, Eddie Nguyen, Amanda Kaatz, Henrik Bringsøe and Attapol Rujirawan.