Sumatran pit viper
Trimeresurus sumatranus (Raffles, 1822)
This large viper is a rare inhabitant of rainforests on the Malay peninsula and Indonesia. Within Thailand it only occurs in a small area of the country where densities are very low making it one of the most elusive reptiles in the area.
I wanted to follow up on my trip down the southern peninsula which I did in August 2022 so I made another visit over the Christmas holidays. This time with five friends from Belgium; Peter, Anniek, Jeroen, Loïc and Nicky. Their road trip started off in Phuket so I was able to show them some of my local spots and not surprisingly a number of known individuals of the Phuket pit viper (T.phuketensis) were easily found. Other highlights included finding a 4.5 metre reticulated python (M.reticulatus) and a large Cantor’s mud snake (Cantoria violacea) which I had not seen before.
Phuket
Krabi/Trang
Moving onto the peninsula and a stop in some mangroves produced a good amount of snakes; reticulated python, mangrove cat snake (B.dendrophila), monocled cobra (N.kaouthia), mangrove pit viper (T.purpureomaculatus) and two crab-eating mud snakes (Fordonia leucobalia), another new species for me! At another spot a few common wolf snakes (L.capucinus) and Oriental vine snakes (A.prasina) were found but not much else.
Yala/Narathiwat
Now for the really exciting part…Upon our arrival in the south the entire lowland areas were flooded and we were worried that we would not reach our next destination. Oddly, during the next five days we had virtually no rain, this was surprising as December is usually the wettest month in this area. We had some long searches without too many results, but gradually we started to find some interesting species. Although not quite as abundant as during my August visit, we had around 10 Hagen’s pit vipers (T.hageni), including a giant 1.2 metre female. Another snake highlight was a juvenile orange-necked keelback (Rhabdophis flaviceps) which Loïc found sitting near a temporary rain pool. Other notable snakes found included a dark wolf snake (L.albofuscus), collared reed snake (C.pavimentata), variable reed snake (C.lumbricoidea), many white-spotted slug snakes (P.margaritophorus), rice paddy snake (H.plumbea), several sunbeam snakes (X.unicolor), Malayan banded wolf snake (L.subcintus), and two Malayan kraits (B.candidus). We also had a number of frog targets that I had not seen before, such as Sunda spotted stream frog (Pulchrana sundabarat), red-bellied frog (Phrynella pulchra), Johor flying frog (Zhangixalus prominanus) and white-backed bug-eyed frog (Theloderma licin).
Some more interesting snake finds came on the last two nights. Firstly on the roads were a green trinket snake (G.coeruleum), two freshly killed black-headed collared snakes (S.melanocephalus), and one dead Malayan blue coral snake (C.bivirgatus). Luckily I was able to find a live blue coral snake on the last night! However, we truly saved the best for last. Our final snake from the south was a gorgeous 1.2 metre female Sumatran pit viper (T.sumatranus) which we had almost given up on finding. A truly amazing last minute highlight!
Phattalung/Nakhon Si Thammarat
Heading back up the peninsular we first stopped at an flooded area where we had a number of water snake species, including one tentacled snake (Erpeton tentaculatum). At a drier inland location we found a good number of beautiful pit vipers (T.venustus) as well as sunbeam snake, Jodi’s pipe snake (C.jodiae), striped kukri snake (O.taeniatus) and cave racer (E.taeniura).
Snake species
- Cylindrophis jodiae
- Malayopython reticulatus
- Xenopeltis unicolor
- Pareas margaritophorus
- Cerberus schneiderii
- Erpeton tentaculatum
- Hypsiscopus plumbea
- Enhydris enhydris
- Homalopsis mereljcoxi
- Fordonia leucobalia
- Cantoria violacea
- Fowlea flavipunctatus DOR
- Rhabdophis flaviceps
- Rhabdophis siamensis DOR
- Xenochrophis trianguligerus DOR
- Ahaetulla prasine
- Ahaetulla mycterizans
- Boiga drapiezii DOR
- Boiga cyanea
- Boiga melanota
- Sibynophis melanocephalus DOR
- Lycodon albofuscus
- Lycodon capucinus
- Lycodon subcinctus
- Dendrelaphis caudolineatus
- Dendrelaphis formosus
- Calamaria lumbricoidea
- Calamaria pavimentata
- Oligodon purpurascens
- Oligodon taeniatus
- Ptyas korros
- Gonyosoma coeruleum
- Gonyosoma oxycephalum
- Elaphe taeniura
- Calliophis bivirgatus
- Naja kaouthia
- Bungarus candidus
- Calloselasma rhodostoma DOR
- Trimeresurus hageni
- Trimeresurus phuketensis
- Trimeresurus purpureomaculatus
- Trimeresurus sumatranus
- Trimeresurus venustus
- Tropidolaemus wagleri