TRUONG SON PIT

(Trimeresurus truongsonensis)

This rare and elusive pit viper, endemic to a small part of the Central Annamites, was first recorded from Phong Nha-Ke Bang National Park in Quang Binh province, Viet Nam. However, interviews with local hunters suggest the species can be found elsewhere in Quang Binh as well as in Quang Tri province further south. It was described as a new species in 2004. In 2019, it was recorded for the first time in Laos, near Hin Nam No National Park, which is contiguous with Viet Nam’s Phong Nhe-Ke Bang. https://www.sciencedirect.com/science/article/pii/S2351989421000056?via%3Dihub

It occurs in evergreen forest and limestone karst habitats. Most records of this species came after heavy rain storms, when they were found basking on mossy karst rocks. They are believed to spend most of their time deep in the crevices created by karst formations and are rarely seen in the dry season. Some of their habitat, even within the national parks, is threatened by logging and conversion for agriculture.

An even greater threat to this species is likely to come from the “pet” trade. Many closely related pit viper species are commonly traded and kept as pets, making overharvesting a serious threat to their survival. For instance, the Mangshan pit viper of southern China, a similarly range-restricted endemic and also assessed as Endangered in the IUCN Red List with an estimated population of no more than 500 snakes, is threatened by overharvesting for international trade as pets and for terrarium keeping. Due to this threat, it was listed in 2013 in Appendix II of CITES, regulating international trade.

The Truong Son pit viper, a beautiful and rare snake, would be similarly desirable for collectors of rare reptiles. Among the live wildlife globally traded as pets, snakes and turtles are in the top-five taxa, along with ornamental fish, parrots and other birds. The international convention for regulating international trade in endangered species of wildlife, CITES, lists for regulation only 164 of the 3,000+ snake species in the world. A 2020 study calculated that 6.2 million CITES Appendix II-listed live snakes were traded in the 44 years between 1975 and 2018. But this number reflects only a small percentage of the actual volume of snakes traded legally but not regulated by CITES and those illegally traded.