Walking through a darkened forest in Thailand, scientists scanned their surroundings. The sound of a rushing waterfall filled the air as they approached a small, rocky stream.
High above, a creature sat perched on a bamboo branch. The scientists looked up, spotted the creature and discovered a new species.
Researchers found the animal near the Chao Doi waterfall in Tak Province, according to a study published May 29 in the journal ZooKeys. The lizard was on a branch about 13 feet “above a large granite boulder.”
Researchers took a closer look at the lizard and discovered a new species: Cyrtodactylus denticulatus, or the spiny-tailed bent-toed gecko, the study said.
Bent-toed geckos are arboreal, or tree-dwelling, lizards with a “prehensile tail carried in a tightly coiled position,” researchers said. Typically, these geckos are “generally slow” with “deliberate ‘chameleon-like’ movements.” Their coloring “closely” matches the surrounding plants.
The new species, the spiny-tailed bent-toed gecko, is about 6 inches long and has spiky bumps along its back, sides and tail, the study said. It has an orangish-tan coloring with darker brown markings on its back, photos show.
The spiny-tailed bent-toed gecko was named “denticulate,” meaning “with small teeth,” after the “small tooth-like” spikes on its body, researchers said. Close-up photos of the animal’s tail show the triangular, pointy-looking spikes.
The new species was identified by its “unique” spikes, a characteristic “not observed” in any other bent-toed geckos, the study said.
DNA analysis confirmed the new species was genetically distinct. The new species had between about 8% and about 22% genetic divergence from other gecko species, the study said. Other species recognized as distinct have as little as about 3% genetic divergence.
Researchers identified the new species based on only one specimen and noted that this approach “can be potentially misleading.” Still, they determined the spiny-tailed bent-toed gecko’s high genetic divergence was “compelling” evidence for its identification as a new species.
“Given the general difficulty in finding cryptic arboreal species,” researchers said, “waiting for the acquisition of additional material that does not bear on its species status, in our opinion, is not the best option.”
Identifying the spiny-tailed bent-toed gecko as a new species allows it to be legally protected, the study said. “Undescribed species” are “‘ecological ghosts’ with no legal protection,” researchers said.
“The discovery of (Cyrtodactylus denticulatus) underscores the unrealized diversity of upland ecosystems across Thailand and the urgent need for increased exploration and conservation of these unique imperiled montane refugia, especially in this era of climate change,” researchers said.
The research team included Siriwadee Chomdej, Chatmongkon Suwannapoom, Waranee Pradit, Apichaya Phupanbai and L. Lee Grismer.
Tak province is about 270 miles northwest of Bangkok and along the Thailand-Myanmar border.