‘Cryptic’ creature with ‘golden yellow’ eyes found in cave. It’s a new species
As night fell across northern Thailand, a 1-foot-long creature emerged from its hiding place and climbed along the rocks. Its “golden yellow” eyes scanned the surrounding forest, but it wasn’t the only one looking around.
Visiting scientists watched the “cryptic and elusive” animal — and discovered a new species.
Researchers hiked into the forests and around the rock formations in Phitsanulok Province several times between 2020 and 2024 as part of an ongoing project to survey the region’s snakes, according to a study published April 22 in the peer-reviewed journal Zootaxa.
During the visits, researchers noticed a few snakes with a similar-looking pattern. The blotchy black pattern was very obvious in small snakes but faded and less visible in larger ones, the study said.
Intrigued by this “unusual” change in color, researchers caught several snakes, took a closer look at them, tested their DNA and realized they’d discovered a new species: Trimeresurus cryptographicus, or the cryptic green pit viper.
Cryptic green pit vipers have “long” and “thin” bodies, reaching about 24 inches in length, the study said. Their “triangular” heads have “large” eyes and a “flattened” snout.
The new species’ changes color as it ages, starting out “strongly patterned” as a juvenile but losing its black blotches within about three months and becoming “uniformly green,” researchers said. The color change likely helps young snakes blend into their preferred rocky habitat and older snakes blend into their preferred forest habitat.
Researchers said they named the new species “cryptographicus” after the Greek words for “hidden” and “‘to write’ or ‘to draw’” because its pattern fades as it ages “like some cryptography text.”
A photo shared by Zootaxa in an April 21 post on X, the social media site formerly known as Twitter, shows an adult cryptic green pit viper. Overall, it is “bright grass-green” with a few tiny black spots and a “brick-red” tail, the study said.
Other photos shared on Facebook by study co-author Tan Van Nguyen show some juveniles of the new species.
Cryptic green pit vipers are venomous, nocturnal and were found around a forested cave, the study said. The snakes are generally “elusive” and “quite uncommon,” so much about their lifestyle remains unknown.
So far, cryptic green pit vipers have only been found at Tham Kang Kao Cave in Phitsanulok Province in north-central Thailand, but researchers expect it to be more widespread, the study said.
The new species was identified by its scale pattern, coloring, body size, genitalia and other subtle physical features, the study said. DNA analysis found the new species had at least about 2% genetic divergence from other related snake species.
The research team included Parinya Pawangkhanant, Sabira Idiiatullina, Tan Van Nguyen, Thiti Ruangsuwan, Tomoya Matsukoji, Patrick David, Chatmongkon Suwannapoom and Nikolay Poyarkov.
This story was originally published April 23, 2025 at 9:47 AM with the headline "‘Cryptic’ creature with ‘golden yellow’ eyes found in cave. It’s a new species."
