Scientists have discovered a new “dragon lizard” species in Southeast Asia with remarkable camouflage capabilities that render it “almost invisible” in its natural habitat.
The unique lizard, described for the first time in a study published in the journal Zoological Research, belongs to a family known as Agamidae, many of which are called “dragons” or “dragon lizards.”
The newly identified species is known only from a single limestone outcrop in the jagged and mountainous karst landscape of Khammouan Province in central Laos.
Karst habitats are widely recognized as unique centers of biodiversity that serve as refuges to some of the most threatened species on the planet. The fractured nature of these landscapes—dotted with towers, caves and hills—creates numerous microhabitats with stable climatic conditions to which many animals have become specialized, like the new species.
Nathanaël Maury / Sitthivong et al., Zoological Research 2023
Karst terrain is typically characterized by barren, rocky ground, consisting of soluble rock—such as limestone or gypsum—that features caves, sinkholes, and underground rivers, among other distinctive features. This type of landscape is created by the dissolving effects of underground water on the soluble rock.
A team of researchers have given the previously unknown lizard the scientific name Laodracon carsticola, which references the country and landscape that the reptile was found in. (The word “dracon” is a Latin word of Greek origin meaning “dragon” or “basilisk”.) For the lizard’s common name, the scientists have recommended it be called the “Khammouan karst dragon”.
The elusive medium-sized lizard, which measures less than half a foot in length, is perfectly adapted to life on the limestone rocks and pinnacles that it calls home, according to the researchers.
The lizard has roughly textured scales and bluish gray eyes. Its body is primarily black or slate-gray with some white markings, and some small reddish and bluish spots in certain areas.
To date the species is known only from a very narrow area in the karst landscape—all the individuals observed so far were spotted climbing or perching on the tops of sharp, limestone pinnacles around 160-230 feet above the ground.
Only a few sightings of the new species have been made. The first individual was observed and photographed in August 27, 2022, by Santi Xayyasith—one of the study authors from the National University of Laos—during a bird-watching excursion in the area.
A second individual was observed on October 6, 2022, by a local guide escorting a group of tourists on a zipline course, which researchers subsequently collected. Scientists then collected another individual on February 2, 2023 at the same spot on the top of the limestone pinnacle.
Santi Xayyasith / Sitthivong et al., Zoological Research 2023
Given that only two specimens have been collected so far, little is known about the biology of Laodracon carsticola. But the body color of the lizard—a contrasting combination of black and white blotches—corresponds with the color of the limestone karst rocks on which it lives, serving as effective camouflage.
“Indeed, when perching on top of limestone karsts, individuals of the new species become almost invisible in the mosaic of sharp shadows and light spots and are difficult to spot unless they start moving,” the authors wrote in the study.
In addition, the roughly textured body scales of the new species may assist in climbing the steep limestone rocks.
The lizard appears to be rock-dwelling and has only been seen on top of the karst pinnacles in the limestone landscape. This level of specialization is similar to some tree-dwelling members of the Agamidae family, which rarely ever venture near the ground.
“The local people said this species is rare and was never recorded outside the limestone habitat on the ground,” the authors wrote in the study.
The lizard appears to be active in the late morning and late afternoon, while its diet likely consists of ants, according to the study.
Sitthivong et al., Zoological Research 2023
After collecting the unusual lizards, the researchers conducted a genetic analysis to determine whether the specimens represented a new species. This revealed that the lizard should be classified in an entirely new genus (group of species) in a subfamily of the Agamidae group known as Draconinae.
An examination of its body also indicated that the new lizard is distinguished from all others in the Draconinae subfamily by its notably swollen tail base, which features distinctive enlarged scales.
Further research is required to understand more about the life history, distribution and conservation status of the new species. But it is possible that the lizard is also found in other surrounding areas given that the karst landscape extends into other parts of central Laos and adjacent portions of Vietnam.