Introduction
Expedition Malaysia 2026 marked our third running of this trip since 2024, and by far our biggest. A record number of bookings meant we brought in additional guiding staff, and the itinerary itself was overhauled from previous years, extending into new territory with five nights in Kelantan, along with the usual stops in the Cameron Highlands and Fraser's Hill. With our strongest team on the ground and a refined route, the potential for this trip was massive, and the results certainly lived up to expectations.
To book Expedition Malaysia in December 2027, click here!
Nights 1-2: Cameron Highlands
After meeting with the group in Kuala Lumpur, we immediately drove three hours to the Cameron Highlands. This cool-weather climate is home to a unique and fascinating array of highland-restricted species, where we were aiming to find as many of the area's endemics as possible.
Unfortunately, we were subjected to intermittent rains for the entirety of our first night in the field, which often limits herpetofauna activity in this area. However, we still found several Cameron Highlands micro-endemic reed snake (Macrocalamus) species moving around on the dry embankments, as well as the highland-endemic Gunung Inas keelback (Hebius inas) and Mirkwood forest slug snake (Astheodipsas lasgalenensis).
Unfortunately, we were subjected to intermittent rains for the entirety of our first night in the field, which often limits herpetofauna activity in this area. However, we still found several Cameron Highlands micro-endemic reed snake (Macrocalamus) species moving around on the dry embankments, as well as the highland-endemic Gunung Inas keelback (Hebius inas) and Mirkwood forest slug snake (Astheodipsas lasgalenensis).
While the rains make it hard to find the rare targets such as the red bamboo ratsnake (Oreocryptophis porphyraceus), these conditions are optimal for finding vipers, and our group turned up a big female Cameron Highlands pit viper (Trimeresurus nebularis). These used to be very common in the Cameron Highlands, but we have noted distinct declines throughout our herping sites - so this is a very welcome find on the first night.
Even better, when the previously intermittent rain progressed into an endless downpour, we switched our focus to road cruising. This produced an incredible adult female Malayan mountain pit viper (Ovophis convictus). While these are encountered semi-frequently in places like Fraser's Hill, the Cameron Highlands population is significantly rarer - making this one of our better encounters of the expedition.
Schulz's reed snake (Macrocalamus schulzi).
Tweedie's reed snake (Macrocalamus tweediei).
Gunung Inas keelback (Hebius inas).
Mirkwood forest slug snake (Asthenodipsas lasgalenensis).
Cameron Highlands pit viper (Trimeresurus nebularis).
Malayan mountain pit viper (Ovophis convictus).
The following day, we tried to do some daytime searching, but more rain rolled in and cut our attempts short. After dinner, the rain had stopped but left us with a very wet and cold night - more sub-optimal conditions. This led to many of the same encounters as yesterday, albeit with the addition of a Butler's mountain wolf snake (Lycodon butleri) and an unexpected brown kukri snake (Oligodon purpurascens). While a repeat species, we were also very happy with an even bigger Cameron Highlands pit viper (Trimeresurus nebularis) from almost 2,000 metres above sea level.
Mirkwood forest slug snake (Asthenodipsas lasgalenensis).
Butler's mountain wolf snake (Lycodon butleri).
Malaysian mountain dragon (Malayodracon robinsonii).
Cameron Highlands pit viper (Trimeresurus nebularis).
Purple kukri snake (Oligodon purpurascens).
Nights 3 - 7: Kelantan
The next morning, we began the drive to Kelantan, encountering the endemic shen long crested lizard (Bronchocela shenlong) crossing the road before we left the Cameron Highlands. Once we had sorted out all the guests rooms, unloaded our gear, and had dinner, it was time to get out for herping.
The night started with a white-spotted cat snake (Boiga drapiezii) crossing the road near our accommodation. Once out on the trails, we were immediately greeted by a stunning adult female Wagler's pit viper (Tropidolaemus wagleri) - several of the guests' biggest target for the trip. Further down the trail, we found an elegant bronzeback (Dendrelaphis formosus), and even further still, a stunning juvenile Sumatran pit viper (Trimeresurus sumatranus). The sumatran pit viper is one of the rarest pit vipers in mainland Southeast Asia, having seen massive declines due to degradation of its primary rainforest habitat. This is one of the few remaining localities with a known population, but the population is dwindling fast, so finding a living juvenile here is a great sign.
Further finds included mating oriental vine snakes (Ahaetulla prasina) very high in a tree, a keeled slug snake (Pareas carinatus) and two Malayan kraits (Bungarus candidus) - our first elapid species of the trip.
Shenlong crested lizard (Bronchocela shenlong).
Kelantan.
White-spotted cat snake (Boiga drapiezii).
Hiking in Kelantan.
Wagler's pit viper (Tropidolaemus wagleri).
Elegant bronzeback (Dendrelaphis formosus).
Keeled slug snake (Pareas carinatus).
Malayan krait (Bungarus candidus).
Sumatran pit viper (Trimeresurus sumatranus).
Sumatran pit viper (Trimeresurus sumatranus).
The second day in Kelantan was very hot and dry, which made hiking in the primary rainforest nowhere near as productive as the previous evening. However, we were still able to find a second juvenile Sumatran pit viper (Trimeresurus sumatranus) deep in the valleys, as well as a smooth-skinned bug-eyed frog (Theloderma licin).
The teams which went road cruising had much better success, producing a myriad of snakes. The best find was undoubtedly an adult Sumatran spitting cobra (Naja sumatrana) of what we call the "hybrid morph", showing traits of both the dark Malaysian form and the brightly coloured Thai phenotype. Another great encounter was a very large Malaysian blue coral snake (Calliophis bivirgata flaviceps). Other encounters included a speckle-bellied keelback (Rhabdophis chrysargos), scarce wolf snake (Lycodon effraenis), dark-headed cat snake (Boiga nigriceps), sunbeam snake (Xenopeltis unicolor), white-spotted slug snake (Pareas margaritophorus) and dusky wolf snake (Lycodon albofuscus).
Sumatran pit viper (Trimeresurus sumatranus).
Giant green-eyed gecko (Gekko hulk).
Smooth-skinned bug-eyed frog (Theloderma licin).
White-spotted cat snake (Pareas margaritophorus).
Sunbeam snake (Xenopeltis unicolor).
Scarce wolf snake (Lycodon effraenis).
Speckle-bellied keelback (Rhabdophis chrysargos).
Dusky wolf snake (Lycodon albofuscus).
Dark-headed cat snake (Boiga nigriceps).
Malaysian blue coral snake (Calliophis bivirgata flaviceps).
Sumatran spitting cobra (Naja sumatrana).
Sumatran spitting cobra (Naja sumatrana).
Day 5 - Berastagi/Ketambe
We continued right where we left off the following morning (finding Calamaria), when Tomasz spotted a Variable reed snake (Calamaria lumbricoidea) sticking its head out from a pipe on the side of a building while we were packing the cars.
After almost 6 hours of driving, we had made our way to the valleys of Mount Leuser National Park in Aceh province, and got checked in to our forest guesthouse and prepared for herping. While people were still getting ready in the rooms, Rupert found a large female Wagler's pit viper (Tropidolaemus wagleri) resting on some low vegetation right behind the bungalow, quickly followed by a large sunbeam snake (Xenopeltis unicolor). While still exploring the garden, Tobias spotted a small snake disappearing into a crevice in a wall. We just got the tip of its tail, gently pulling it out to reveal one of our ultimate dream species for the area.
The small snake disappearing into the crevice was the mythical three-striped kukri snake (Oligodon trilineatus), only photographed once before (in 2003). We are rare Oligodon enthusiasts and getting this within the first hour on the first night felt surreal. This snake is an accurate mimic of the Malaysian highland form of the Malayan banded coral snake (Calliophis intestinalis), although strangely this particular morph does not occur in Sumatra (as far as we know).
We continued herping along a forest stream and found many more snakes, including a heavily black-banded individual of Hagen's pit viper (Trimeresurus hageni), white-bellied ratsnake (Ptyas fusca), striped bronzeback (Dendrelaphis caudolineatus), Malayan vine snake (Ahaetulla mycterizans) and speckle-headed vine snake (Ahaetulla fasciolata). Returning back to the resort, we also found a Malaccan slug snake (Asthenodipsas cf. malaccanus) and an adult female Hagen's pit viper (Trimeresurus hageni). Our first and only 10 snake species day of the trip.
Variable reed snake (Calamaria lumbricoidea).
Calamaria goofiness.
Wagler's pit viper (Tropidolaemus wagleri).
Wagler's pit viper (Tropidolaemus wagleri).
Three-striped kukri snake (Oligodon trilineatus).
Hagen's pit viper (Trimeresurus hageni).
Malayan vine snake (Ahaetulla mycterizans).
Malaccan slug snake (Asthenodipsas cf. malaccanus).
Malayan flying frog (Zhangixalus prominanus).
Harlequin flying frog (Rhacophorus pardalis).
Hagen's pit viper (Trimeresurus hageni).
Day 6 - Ketambe
We went out herping the following day and even though we did not see any herpetofauna, we were very happy with a real wild orang-utan sighting, a female with two offspring - one a tiny baby. The nighttime search was much less productive than the previous day. We tried some new trails which were incredibly dry due to this being the very end of the dry season after around 2 months of very little rain. Exploring closer to a river, we found a huge Hagen's pit viper (Trimeresurus hageni) with a yellowish colour, along with a Malayan banded wolf snake (Lycodon subcinctus) and a Brahminy blind snake (Indotyphlops braminus). Back at the resort, we saw several more Malayan vine snakes (Ahaetulla mycterizans) and another huge female Hagen's pit viper (Trimeresurus hageni) - this time almost entirely green in colour. We were also very happy with a Chameleon angle-headed lizard (Gonocephalus cf. chameleotinus).
Wild orangutan.
Swimming in the river beside our guesthouse.
Kuhl's gliding gecko (Gekko kuhli).
Ichthyophis paucisulcus.
Long-nosed horned frog (Pelobatrachus nasuta).
Brahminy blind snake (Indotyphlops braminus).
Malayan banded wolf snake (Lycodon subcinctus).
Hagen's pit viper (Trimeresurus hageni).
Hagen's pit viper (Trimeresurus hageni).
Chameleon angle-headed lizard (Gonocephalus cf. chameleotinus).
Day 7 - Ketambe
Our third day in Ketambe came alive when we were flagged down in our cars by a local ranger we had befriended on the previous days, who was shouting "we have snake!". Sure enough, inside the kitchen of his house was a keeled rat snake (Ptyas carinata) in the process of eating a river toad. The snake freaked out and dropped the toad as soon as we entered the room, so we captured and released it nearby.
We tried yet another trail at night, focusing on searching forest-edge plantations in the hopes of encountering some different species. This turned up a large dog-toothed cat snake (Boiga cynodon) - finally breaking our streak of no-Boiga days - and 2 further Brahminy blind snakes (Indotyphlops braminus). Back at the resort, Braeden found a beautiful Jasper cat snake (Boiga jaspidea) along with some nice frogs which were new for the trip.
Keeled rat snake (Ptyas carinata).
Keeled rat snake (Ptyas carinata).
Dog-toothed cat snake (Boiga cynodon).
Chasen's frilled tree frog (Kurixalus chaseni).
Cinnamon frog (Nyctixalus pictus).
Jasper cat snake (Boiga jaspidea).
Day 8 - Ketambe
After 2 slow days with extremely dry weather, we were in dire need of rain to boost activity to drizzly first-night levels, and that's exactly what we got. A big storm rolled in at sunset and finally doused the area in rain. This immediately improved our success rate, kicking things off with a striped bronzeback (Dendrelaphis caudolineatus) in the late afternoon.
After dark, we hiked a stream and found several Hagen's pit vipers (Trimeresurus hageni), more vine snakes (Ahaetulla mycterizans and Ahaetulla fasciolata), and two new species for the trip; an elegant bronzeback (Dendrelaphis formosus) and a Malayan bridle snake (Dryocalamus subannulatus). Further searching around our resort produced several more species, such as a male Wagler's pit viper (Tropidolaemus wagleri), multiple sunbeam snakes (Xenopeltis unicolor) and a white-spotted cat snake (Boiga drapiezii).
However, the best find was undoubtedly 2 dragon snakes (Xenodermus javanicus) - found just meters behind our bungalows in a small stream. Both were relatively large individuals which were hunting amongst the rocks and fallen logs during a period of heavy rain which continued late into the night. A fantastic and much-awaited showstopper - a first record for the area as well.
Striped bronzeback (Dendrelaphis caudolineatus).
Habitat of many of the species found during this trip.
Elegant bronzeback (Dendrelaphis formosus).
Malayan bridle snake (Dryocalamus subannulatus).
White-spotted cat snake (Boiga drapiezii).
Dragon snakes (Xenodermus javanicus).
Dragon snake (Xenodermus javanicus).
Day 9 - Ketambe
Our final day in Ketambe was spent without water, as the water supply to our rooms was damaged and the river was too powerful and full of debris to bathe in anymore. However, this did not affect our morale to seek out the last key species we were missing from our time here - the lowland leaf-nosed pit viper (Craspedocephalus cf. borneensis) - which we were hoping had been brought out by the heavy rains the night before. Hereby, we embarked at twilight on a hike deep into the primary rainforest.
Not long into our hike, the group stopped to examine the roots of a huge dipterocarp tree for this cryptic pit viper, and moments later Rupert exclaimed "got one!" - revealing an absolutely stunning green and pink juvenile in a perfect ambush position in the roots. We continued into the valley despite more heavy rain arriving, finding several more species along the way. This included many Malayan vine snakes (Ahaetulla mycterizans), a large Malaccan slug snake (Asthenodipsas malaccanus), a juvenile white-spotted cat snake (Boiga drapiezii), a juvenile Wagler's pit viper (Tropidolaemus wagleri), a striped bronzeback (Dendrelaphis caudolineatus) and 2 more leaf-nosed pit viper (Craspedocephalus cf. borneensis). These 2 further Craspedocephalus were an impressive adult male and a sub-adult female. We also saw several interesting lizards on this absolutely fantastic final hike in the lowlands.
Not to be outdone, the male wagler's pit viper (Tropidolaemus wagleri) we had found the previous night had begun the mating process with the same large female from night 1, which had been hanging out in the same area behind our bungalows for the whole trip!
In-situ juvenile leaf-nosed pit viper (Craspedocephalus cf. borneensis).
Juvenile leaf-nosed pit viper (Craspedocephalus cf. borneensis).
Heading into the jungle after sunset.
Various repeat finds.
Female leaf-nosed pit viper (Craspedocephalus cf. borneensis).
Male leaf-nosed pit viper (Craspedocephalus cf. borneensis).
Left: Aphaniotis acutirostris. Right: Unknown Sphenomorphus sp.
Courting Wagler's pit vipers (Tropidolaemus wagleri).
Day 10 - Berastagi
To break up the almost 9 hour drive back to Medan, we stopped for one final night of herping in the highlands of North Sumatra, and one final chance to search for our biggest highland targets. We began the evening searching at the mid-montane site which had turned up 7 species of snake in 1 night earlier in the trip, but over 2 hours herping here failed to produce a single individual this time.
Hereby, we switched to the upper elevations and began grinding once again for Harpesaurus and Oligodon petronellae. Within just a few minutes of hiking, Rupert found two more Manthey's mountain lizards (Gonocephalus lacunosus) sleeping beside each other - the male being even larger than the individual we saw during our first stint here. He subsequently called over the group to look at these two lizards, and while walking over Braeden spotted a little snake half-hidden inside a hole in the bank of the trail. We got it out to reveal an absolutely stunning Petronella's kukri snake (Oligodon petronellae), one of the best possible encounters on our last day here!
The fun did not end here though, as we went on to find the 2 'common' species in the area which had somehow evaded us through all our searching over the first 4 days in the highlands; the Sumatran slug snake (Asthenodipsas tropidonotus) and Schlegel's reed snake (Calamaria cf. schlegeli). This slug snake is possibly the largest member of the Pareatidae group. While this was the last of our personal finds, we got to see two more snakes which Eddy and Radit had sourced from locals during the days we were away. The first was a huge and absolutely incredible red bamboo ratsnake (Oreocryptophis porphyracea laticinctus), a target which had evaded us this time, and a baby Sumatran cobra (Naja sumatrana) - a species we had only seen fresh DOR on this trip.
Pizza for our final dinner.
Male & female Gonocephalus lacunosus.
Cyrtodactylus sp.
Schlegel's reed snake (Calamaria cf. schlegeli).
In-situ Oligodon petronellae.
Petronella's kukri snake (Ologodon petronellae).
Huge Sumatran slug snake (Asthenodipsas tropidonotus).
Red-bamboo ratsnake (Oreocryptophis porphyracea laticinctus).
Sumatran cobra (Naja sumatrana).
And that concludes our first ever Expedition Sumatra. While not every night was packed to the brim with countless crazy observations and encounters, the overall quality from start to finish was simply sensational, and this certainly stands out as one of the best trips ever for "rare" species - with so many seldom seen or documented species found at both locations. Getting both of our main target kukri snakes for Northern Sumatra was also unprecedented. We cannot wait to build upon this success next year...
To join our next Expedition Sumatra (6th - 16th March 2026), click here!
FULL SPECIES LIST:
Snakes
Colubridae:
Ahaetulla fasciolata - 3
Ahaetulla mycterizans - 20+
Ahaetulla prasina - 2
Boiga cynodon - 1
Boiga drapezii - 2
Boiga jaspidea - 1
Dendrelaphis caudolineatus - 3
Dendrelaphis formosus - 1
Dryocalamus subannulatus - 1
Lycodon subcinctus - 1
Elaphe taeniura grabowskyi - 1
Elapoidis sumatranus - 3
Oligodon trilineatus - 1
Oligodon cf. pulcherrimus - 1
Ptyas carinata - 1
Ptyas fusca - 1
Calamaria lumbricoidea - 1
Calamaria cf. schlegeli - 2
Calamaria cf. virgulata - 2
Calamaria abstrusa: 4
Pseudorabdion cf. longiceps - 1
Paretidae:
Asthenodipsas laevis - 1
Asthenodipsas malaccanus - 2
Asthenodipsas tropidonotus - 1
Pareas carinatus - 1
Viperidae:
Craspedocephalus andalasensis - 2
Craspedocephalus cf. borneensis - 3
Trimeresurus gunaleni - 7
Trimeresurus hageni - 7
Trimeresurus sabahi toba - 5
Tropidolaemus wagleri - 3
Elapidae:
Bungarus flaviceps - 1
Calliophis intestinalis - 1
Xenodermidae:
Xenodermus javanicus - 2
Xenopeltidae:
Xenopeltis unicolor - 7
Typhlopidae:
Indotyphlops braminus - 3
Ramphotyphlops lineatus - 1
Lizards:
Aphaniotis acutirostris
Dendragama boulengeri
Dendragama stejnengeri
Bronchochela cristatella
Bronchochela hayeki
Gonocephalus luncanotus
Gonocephalus cf. chameleotinus
Draco sumatranus
Cyrtodactylus quadrivirgatus
Cyrtodactylus lateralis
Cyrtodactylus sp.
Gekko kuhli
Gehyra mutilata
Hemiphyllodactylus cf. typus
Hemidactylus frenatus
Hemidactylus platyurus
Eutropis multifasciata
Varanus salvator
Dibamus sp.
Sphenomorphus sp.
Sphenomorphus sp2.
Laturia cf. sumatrensis
Amphibians:
Duttaphrynus melanistictus
Phrynoidis juxasper
Kurixalus chaseni
Zhangixalus achantharrhena
Zhangixalus prominanus
Polypedates leuxomystax
Polypedates discantus
Polypedates macrotis
Rhacophorus pardalis
Rhacophorus calamitas
Philautus petersi
Nyctixalus pictus
Leptomantis pseudacutirostris
Microhyla cf. supracilliaris
Microhyla cf. annectens
Microhyla heymonsi
Megophrys parallela
Pelobatracus nasuta
Odorrana hosii
Sumaterrana crassiovis
Hylarana fantastica
Hylarana sp.
Chalcorana parvaccola
Fejervarya limnocharis
Limnonectes sp.
Wijayarana sumatrana
Ichtyophis paucisulcus
86 total herpetofauna species observed and photographed.
From Eddy and Radit:
Naja sumatrana - 1
Oreocryptophis porphryaceus ssp. - 1
DOR:
Dendrelaphis kopsteini - 1
Pareas carinatus - 1
Naja sumatrana - 1
Calamaria lumbricoidea - 1
Calamaria schlegeli - 1
Elaphe taeniura grabowskyi - 2
Coelognathus flavolineatus - 5
Dendrelaphis cyanochloris - 1
