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New From Southeast Asia – Yellow and Red Eyed Vipers and a Giant Cave

Politics and war have long hindered the work of resident and foreign biologists inVietnam and elsewhere inSoutheast Asia. Governmental red tape is also a serious concern…several years ago I obtained funding to study salamanders in northernVietnam, but abandoned the project for this reason. However, the situation is improving, and recent expeditions have brought a host of amazing new creatures and places to light, including 2 beautiful arboreal snakes and a cave housing a large, underground river.

Ruby-Eyed Green Pit Viper, Cryptelytrops rubeus

Southeast Asia’s pit vipers are a confusing jumble of similarly-colored venomous snakes that are supremely adapted to life in the trees. Many were originally classified in the genus Trimeresurus, along with the Bamboo Viper (please see photo) and related snakes. Genetic research and behavioral studies on specimens collected from 1999-2003 has revealed at least 2 new species.

Originally thought to be a variant of the Big-Eyed Viper, Crypteltrops macrops (please see photo), the Ruby-Eyed Pit Viper has recently (March, 2011) been classified as a distinct species, the snake world’s newest.  It inhabits forests near Ho Chi Minh City and elsewhere in southern Vietnam and eastern Cambodia, but virtually nothing is known of its natural history.

Yellow-Eyed Green Pit Viper

Also newly-described is the Yellow-Eyed Green Pit viper, C. cardumonensis.  Native to southeastern Thailand and southwestern Cambodia, it too is little-studied and difficult to locate.

Both new pitvipers may be threatened by habitat loss and collection for the medicinal and leather trades, but more field studies are needed before conservation measures can be suggested.

Giant Cave Hides a Mighty River

River Cave In Central VietnamI still find it hard to imagine that a place such as Hang Son Doong Cave (please see article below) exists. Situated on the Laos-Vietnam border, it hides what may be the world’s largest underground river; some of its chambers are tall enough to engulf the Empire State Building.

Where the cave roof has collapsed, tropical forests flourish – essentially below-ground, yet exposed to the light. Biologists have found monkeys and scores of smaller creatures here, but know nothing of their habits or interactions, if any, with the “outside world. Pure white crustaceans and fishes, almost certainly species new to science, have been seen in the cave’s subterranean waters.

Amazingly, local people knew of the cave’s existence but its jungle-shrouded entrance was apparently not discovered until the 1970’s, by Ho Khanh, who was a boy at the time. It took 3 expeditions in the early 1990’s before cavers, led by Mr. Khanh, could relocate and explore the cave.  The January, 2011 issue of National Geographic Magazine features the story and a wonderful series of truly astonishing photos.

Further Reading

Photos of the Ruby-Eyed Pit Viper

Zootaxa article describing the new pitviper

Hang Son Doong Cave





Trimeresurus albolabris image referenced from wikipedia and originally posted by DJatmiko




  1. avatar

    Its at least nice to be reminded every once in a while that we still haven’t figure it all out

About Frank Indiviglio

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Being born with a deep interest in animals might seem unfortunate for a native Bronxite , but my family encouraged my interest and the menagerie that sprung from it. Jobs with pet stores and importers had me caring for a fantastic assortment of reptiles and amphibians. After a detour as a lawyer, I was hired as a Bronx Zoo animal keeper and was soon caring for gharials, goliath frogs, king cobras and everything in-between. Research has taken me in pursuit of anacondas, Orinoco crocodiles and other animals in locales ranging from Venezuela’s llanos to Tortuguero’s beaches. Now, after 20+ years with the Bronx Zoo, I am a consultant for several zoos and museums. I have spent time in Japan, and often exchange ideas with zoologists there. I have written books on salamanders, geckos and other “herps”, discussed reptile-keeping on television and presented papers at conferences. A Master’s Degree in biology has led to teaching opportunities. My work puts me in contact with thousands of hobbyists keeping an array of pets. Without fail, I have learned much from them and hope, dear readers, that you will be generous in sharing your thoughts on this blog and web site. For a complete biography of my experience click here.
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