Scientists have described a new species of lizard from the high mountain forests of western Thailand, and have given it a name straight out of fantasy television: Acanthosaura syrax, named after Syrax, the dragon ridden by Queen Rhaenyra Targaryen in House of the Dragon.

The lizard belongs to a group known as mountain horned dragons, agamid lizards recognised by the spiny crests running along their neck and back. It was discovered in the evergreen forests of Mae Wong National Park, in the Tak-Kamphaeng Phet Province, at elevations above 1,300 metres, where it appears to live nowhere else. The find brings the total number of known species in the genus Acanthosaura to 23.

The research team, led by Poramad Trivalairat and colleagues from Chulabhorn Royal Academy and Kasetsart University, chose the name Syrax deliberately. The dragon of that name in the fantasy world is known for its striking yellow colouring, its comparatively modest size next to other dragons, and for producing an unusually large number of eggs.

The researchers found all three qualities echoed in the real animal: A. syrax has yellowish-green tones in its colouring, is one of the smallest members of its genus, and lays notably large clutches of eggs for its size. The team has proposed "Syrax mountain horned dragon" as its English common name, alongside a Thai name that translates the same way.

Beyond the name, the lizard stands out for possessing the smallest neck and back crest scales recorded anywhere in the genus, along with an overall small body size. It also lacks a black patch around the eye seen in several related species, and has a distinctive dark collar marking. DNA analysis of two genes backed up what the researchers saw by eye, showing that A. syrax is genetically distinct from its closest relative, A. lepidogaster, and from every other known species in the group.

The species appears to be confined to a narrow band of high-altitude forest, and the researchers say its populations are naturally scattered by the rugged terrain of the mountain range, a state of affairs that leaves it vulnerable should its habitat come under further pressure. They are calling for stronger protection of Mae Wong's high-elevation forests, suggesting the new lizard could serve as a flagship species for the area alongside other rare wildlife found there, including the Asian forest tortoise, Oldham's leaf turtle and the Indochinese tiger.

The study is published in the open-access journal ZooKeys.