Tropidolaemus subannulatus Bornean Keeled Green Pit Viper
Some other names for this species:
Bornean Keeled Pit Viper, North Philippine Temple Pit Viper, Keeled Malaysian Pit Viper
Tropidolaemus subannulatus was split from Tropidolaemus wagleri in 1985.
Santubong Peninsula, Sarawak, MalaysiaJanuary 28, 2017
Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus) Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus) Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus) Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus)
Males and young females of this species were common in the Santubong forests at night. The first three above are males. The third, with red-and-white bands that nearly encircle the body, is a young female.

My Travelogues and Trip Lists page includes a complete list of the herps I saw in the wild on this trip to Malaysia, as well as a travelogue of the trip.

Santubong Peninsula, Sarawak, MalaysiaJanuary 30, 2017
Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus)
What I really wanted to see was an adult female, as they are the most beautiful members of the species. Fortunately for me, an employee of the hotel where I was staying pointed one out to me, a couple of feet from a small wooden building from which they rented kayaks and other watercraft for tourists. He told me she had been in that same spot for three days.
Santubong Peninsula, Sarawak, MalaysiaJanuary 31, 2017
Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus)
The next morning, however, the snake was nowhere to be seen. Later in the day I noticed some hotel guests taking photos of something in the vegetation near the outdoor hotel café, and that something turned out to be another beautiful adult female T. subannulatus. Close inspection of the photos revealed that it was in fact the very same beautiful adult female T. subannulatus.
Kubah National Park, Sarawak, MalaysiaFebruary 19, 2018
Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus)
This unpatterned youngster was my first snake of my 2018 trip to Borneo. Thanks for welcoming me, li'l snake!
Gunung Gading National Park, Sarawak, MalaysiaFebruary 20, 2018
Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus)
The next night I found another, a little bigger and slightly more patterned. Still just a youngster. The rows of red-and-white spots identify this one as a male. A young female would sport narrow red-and-white rings.
Gunung Mulu National Park, Sarawak, MalaysiaFebruary 23, 2018
Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus) Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus)
As the males get older, the red halves of the red-and-white spots fade. This male is probably a fully grown adult.
Gunung Mulu National Park, Sarawak, MalaysiaFebruary 25, 2018
Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus)
Between Kurt and me, we found eight young and/or male T. subannulatus before finally coming across one of the real beauties, an adult female.
Gunung Mulu National Park, Sarawak, MalaysiaFebruary 26, 2018
Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus) Bornean Keeled Green Pit Viper (Tropidolaemus subannulatus)
We liked that adult female so much that we went back to visit her again the following night.
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