12/05/2025
We're a little late to the party, but a couple of weeks ago, friends of ours described a new viper species. Congratulations to the whole team for adding yet another new viper to the fauna of Thailand! I believe that brings the total number of vipers in Thailand to 28 species.
It had been quite a few years since we first saw this species.
Just a couple of months after the start of the covid pandemic in 2020, our friends Alex Mason and Darryl Sweetland found an unusual-looking, little viper (the individual in the first image in this post) on a limestone massif in Phitsanulok province, northern Thailand. This got the adrenaline in our blood pumping, especially after having been locked down at home for several months due to the closure of all national parks in Thailand. At that point it seemed the covid pandemic had been contained fairly well within Thailand, so travel within the country was possible again, with some restrictions. The national parks were still close at that point, so all our tours had been cancelled and we were enjoying the surprising but rather welcome break after years of running a business 24/7.
Together with Rushen Jaihan we jumped in the car shortly after seeing their image of the stunning, heavily banded juvenile viper. And drove the 7:30 hrs to Phitsanulok to join them in the search for more specimens.
We spotted a beautiful turquoise-coloured male that had taken a quite unusual position on a vertical tree trunk (in situ photo can be found in this post). And we found a bunch of other specimens, mostly tiny juveniles. But even though all of them were bearing some unusual black crossbar markings on their body, none of them matched the extreme banded look of that very first specimen that Alex and Darryl had found and had gotten us so excited in the first place.
Their appearance was very similar to the Large-eyed Pit Viper (Trimeresurus macrops) which is common in for example Bangkok and Khao Yai. Albeit with some more distinctive markings. If they hadn't found that very first unusual looking specimen, but rather one of the other more standard-looking individuals, we probably wouldn't have jumped in the car right away, haha. But in hindsight, we're still glad we took that journey to a region we had barely explored.
The authors of the paper on this new species have also chosen for the fitting name, the Cryptic Green Pit Viper, Trimeresurus cryptographicus.
For those interested to read more about the new species, here follows the link to the original paper in which it is described.
https://mapress.com/zt/article/view/zootaxa.5621.5.2