11 Snakes Found In Java (Indonesia)

 

1	Javan keelback

Maximum length: 120cm.

A common snake near watery areas of Java. The Javan keelback (Fowlea melanzosta) is closely related to the checkered keelback of India (Fowlea piscator), and was originally considered to be one of its subspecies, before being declared independent in 1996. This species has a mild venom, which is most likely harmless to humans, but still unresearched. 

Javan keelbacks are abundant on their namesake island, including near the capital of Jakarta. They’re a flexible species, and will appear virtually anywhere in Java with water. This means marshes, the grassy banks of rivers, lake shores, and especially in rice paddies. Another common rice paddy species is the Javan spitting cobra, which almost certainly preys on Javan keelbacks for its meals. 

Javan keelbacks average at 80.5cm long, with the tail comprising 24.8% of body length on average. This is a variable snake in appearance, with two classic morphs: striped and blotched. Some are bright yellow, as shown by this video where a guy holds one in his hand effortlessly, with the keelback staying completely calm.

Javan keelbacks are also present on Bali, and have very sparse numbers in Sumatra, but aren’t found in Sulawesi, peninsular Malaysia or Borneo. Originally, they were believed to live on India’s Andaman islands, but this turned out to be a different species: Xenochrophis tytleri, AKA the Andaman keelback.

 

 

2	Ashy pitviper

Maximum length: 90cm.

The resident tree-dwelling pitviper of Java, as well as Bali and southern Sumatra. Ashy pitvipers might not be found in central Jakarta itself, but they dutifully guard all the forests surrounding it.

This species generally rests on branches, though not 100% exclusively, and reaches a known maximum of 90.0cm. Ashy pitvipers don’t cause legions of deaths per year, but have a strongly haemorrhagic venom, which acts via pro-coagulant means, activating clotting factors so rapidly that none ultimately remain.

Ashy pitvipers (Craspedocephalus puniceus) are a highly variable snake in appearance. They’re generally yellow to grey, smattered with many fine spots that give them their “ashy” name. However, males are far more colourful overall, with far more vividly contrasting patterns. The picture above is probably a female, as its colours are more uniform. Occasionally, you can even find purple varieties of the Ashy pitviper.

Ashy pitvipers are recognisable partly by their jutting snout, and a few elevated supraocular scales, giving them the appearance of having eyelashes. Because of these features, and the fact that they’re rarely a clean pastel green, they’re simple to distinguish from Java’s other tree-dwelling pitviper, Trimeresurus insularis (see below).

 

 

3	Aplopeltura boa

Maximum length: 85cm.

One of Java’s most easily recognisable snakes. This is a bizarre snake with an extremely thin body, combined with a highly rounded head, and large eyes with round pupils.

Blunt-headed slug snakes (Aplopeltura boa) spend most of their lives on branches, hunting for slugs and snails. They suck the latter from their shells using a specialised jaw, with extra teeth in their right side. Instead of sucking the insides free like spaghetti, like similar snakes, they detach the soft part of a snail’s body from its operculum (shell) using a sawing motion.

This species is widespread, ranging from Thailand in the north, through peninsular Malaysia, Sumatra, and finally to Java, where it’s very common, and not at all hard to find (as well as easy to recognise).

Aplopeltura boa is especially concentrated on the slopes of two Javan volcanoes: Mount Salak and Mount Gede. The former last erupted in 1938, and the latter in 1957, but Mount Gede had at least 21 eruptions between 1747 and 1957, with the biggest being in 1840. This spewed a vast amount of pyroclastic flows into the forests below, though thankfully caused no fatalities.

Whether the local Aplopeltura boa populations were affected is a mystery. It’s possible that they saw the lava flows coming, glanced at each other, and all retreated to higher branch perches at once. Either way, they’re still there today.

 

 

4	Malayan banded wolf snake

Maximum length: 105cm.

The Lycodon wolf snake genus has 73 members worldwide, but the Malayan banded wolf snake (Lycodon subcinctus) is one of the more widespread, ranging from Thailand to Malaysia to Brunei. Java is yet another of its strongholds, from east to west, including near the capital of Jakarta.

This species is completely non-venomous, and primarily inhabits forest floors. Malayan banded wolf snakes primarily hunt reptiles, such as geckos and tiny skink lizards, which they stalk through the forest and eventually constrict to death. 

Malayan banded wolf snakes are safe to pick up, but extreme caution is advised. This species is a blatant mimic of the severely neurotoxic blue krait (Bungarus candidus), one of Java’s deadliest snakes, whose bite regularly has lethal consequences (easily more dangerous than most pitvipers). The black and white bands are a clear match, as are their forest floor habitats.

There’s one clear difference, as the blue krait tends to have more evenly spaced black-white bands, while in the wolf snake, the black spaces are significantly longer. But if you encounter either, take a step back, just to be sure. Do not engage unless you’re a herpetological expert. A trip to Java can still be lethal in the 21st century. 

 

 

5	Red pipe snake

Maximum length: 90cm.

This species is known by two common names: red-tailed pipe snake and red cylinder snake. Both names are similar, and the reason is their extremely round body in a cross section, the exact opposite of a US corn snake, which has a completely flat belly to allow it to dig into tree bark while climbing. Red cylinder snakes have a different goal: forging a path through layers of rotting leaf litter covering the forest floor.

Red-tailed pipe snakes (Cylindrophis ruffus) are common all over southeast Asia, and Java is a particular base. Of all their hotspots, Jakarta and its outskirts may have the highest number of dots on the map. While not aquatic, they tend to appear in microhabitats adjacent to water, such as the roots of long grass by a river, or moist, waterlogged leaf litter by a forest stream.

Red-tailed pipe snakes are perfectly safe to pick up, with no venom whatsoever. Most of their diet consists of elongated prey like fellow snakes and eels. Red-tailed pipe snakes are also named for their bright red tail, which they wiggle to distract enemies when flustered. An iridescent sheen is another of their characteristics.

Red-tailed pipe snakes are generally dark with multiple overlapping bands, but in certain individuals, these are faded and much harder to spot (though still present). The bands themselves vary from yellow to white.

 

 

6	Orange-bellied snake

Maximum length: 40cm.

One of Java’s subtlest, stealthiest snakes. You won’t turn a corner and find a hissing orange-bellied snake blocking the entrance to your hotel, which is perfectly possible with a Javan spitting cobra. Orange-bellied snakes are widespread, ranging from peninsular Malaysia to Singapore to Sumatra to Java. Yet despite this large empire, they’re surprisingly poorly researched, mostly due to their secretive ways.

Orange-bellied snakes (Gongylosoma baliodeira) spend their days lurking on thick forest floors, sometimes straying to grassy clearings adjacent to forests. From above, they’re a simple dull brown, with occasional snowy white marks. However, their underside is much more colourful. The exact intensity of the belly varies, as in some snakes, it’s a full fiery orange, while in others it’s much paler.

Orange-bellied snakes were originally assumed to be nocturnal, until numerous images appeared of them slithering in broad daylight with a focussed, alert expression. Alongside insects and tiny lizards, this species is confirmed to prey on spiders. Like any snake, it swallows them whole, 8 legs and hairy body. As this species lacks a powerful venom or constricting skills, these spiders are swallowed alive.

 

 

7	Eight lined striped kukri snake

Maximum length: 68cm.

Part of the vicious, ripping, tearing kukri snake clan. The 88 member Oligodon genus lacks any form of venom, but does have especially sharp front fangs. The eight-lined striped kukri snake (Oligodon octolineatus) is one of Java’s more flexible species, appearing in forests, fields, parks, gardens, and suburban areas alike. This species is most common in western Java, and has even been found in Jakarta itself. 

Eight-lined striped kukri snakes are non-venomous, but should never be picked up, due to their aggressive nature. Further afield, they also inhabit Sumatra, Singapore and Malaysia (east and west). When flustered, this species will display the bright, vivid underside of its tail, in an attempt to distract predators.

This species is simple to recognise up close because of its namesake lines. The stripe directly down the spine (vertebral stripe) is a bright orange. Adjacent on each side is a vivid black stripe, while the next stripe is a pale grey. Though the exact thickness of the parallel stripes varies, the colours are fairly consistent, especially the orange vertebral stripe.

Eight-lined kukri snakes only peak at 68cm, but their bright colours help them to stand out. Another common species on Java is the brown kukri snake (Oligodon purpurascens). Nobody could confuse the two, as this species has large, irregular brown blotches, and is much less colourful, with pale brown set against slightly darker brown.

 

 

8	Lesser Sunda pitviper

Maximum length: 93cm.

Lesser Sunda pitvipers (Trimeresurus insularis) are found across Indonesia’s various Lesser Sunda islands, the largest of which is the tourist hotspot of Bali. They’re particularly common near the Bali capital of Denpasar, but they also have a large presence in the eastern half of Java. This species is famous for being one of the bluest snakes worldwide, as while the majority are jungle green, with a white line on their flanks, a sizeable portion are sky blue and remain that way for life.

Lesser Sunda pitvipers are mainly found in forests at altitudes of up to 1200 metres. This species is a very imaginative hunter. One of their strategies is to rest on branches directly adjacent to sheer limestone cliff walls, and wait patiently for climbing lizards to run up the rocky face. When the moment comes, they pluck these lizards off with a sudden extension of their coiled body.

Lesser Sunda pitvipers can ambush prey 5-15 metres high in the tree canopy, but also on vegetation close to the ground. They even possess a brightly coloured tail tip which they move in a slow, rhythmical fashion, in order to lure in curious amphibians.

Fortunately, humans are not susceptible to this hypnosis. If a Lesser Sunda pitviper sinks its teeth into you, then you can expect swelling, agonising pain and possibly necrosis, but most likely not death. One of their confirmed prey is Boulenger’s pipe snake (Cylindrophis boulengeri), a close relative of the red-tailed pipe snake mentioned earlier on this list, meaning that this too may be part of their diet.

 

 

9	Striped keelback

Maximum length: 70cm.

The striped keelback (Xenochrophis vittatus) is a semi-aquatic species of Java, which is common in small streams, ponds, rice paddies, and even near people’s houses. This is a frog and fish-eating species which often appears in backgardens, and sometimes climbs onto low vegetation like bushes in its curious quests for food.

This is a harmless snake, which has never killed a human being. Striped keelbacks are fairly easy to recognise, as they have patterns arranged in parallel stripes, running lengthways down their entire body. Their most recognisable markings are on their flanks – a series of rapidly alternating black and white markings like teeth, or a saw’s blades. Their upper back usually has brown-orange stripes, alternating sharply with black.

The striped keelback is found all over Java. Elsewhere, it has a presence in the jungles of Sumatra, and was introduced artificially in Singapore into its Sungei Buloh wetland reserve (a popular bird watching spot). Weirdly, they’ve also been spotted in Puerto Rico, where they’re assumed to have escaped from overseas shipping containers in 1994 or earlier.

Striped keelbacks coexist on Java with their relative the triangle keelback (Xenochrophis trianguligerus), but this has totally different patterns, with blotches instead of neat and ordered lines.

 

 

10	Variable reed snake

Maximum length: 64.2cm.

One of the most variable snakes in Java, and indeed the world. The variable reed snake is the most common member of the massive Calamaria genus (66 members), also occupying Malaysia, Sumatra, Singapore and parts of the Philippines. Java is one of their strongholds, where as usual, they tend to appear on leafy forest floors.

The variable reed snake (Calamaria lumbricoidea) has an immense variety of colour morphs and pattern morphs, despite all individuals somehow being part of the same species. The picture above is almost a clone of the lethal Malaysian blue coral snake, with the classic red head, and only slightly less blueness. Others are black sharply contrasting with yellow, while others are brown with occasional white markings, similarly to a wolf snake.

The purpose of this is probably to mimic more dangerous snakes, and vary their colours depending on which dangerous snake is more common in certain locations. Deception is really all this species has when it comes to defence. The variable reed snake has no venom, and lacks a pair of sharp, ripping fangs. Their only alternative strategy is burying themselves in the mulchy forest floor, hoping that nobody notices their existence. Earthworms constitute the main prey of this species.

 

 

11	Many-spotted catsnake

Maximum length: 187cm.

The most common Boiga catsnake species on Java. Other residents include the dog-toothed catsnake and black and yellow mangrove catsnake, but the many-spotted catsnake (Boiga multomaculata) is everywhere, including near the capital of Jakarta.

This species doesn’t shy away from human zones. It’s a branch-dwelling snake which hisses and mock lunges from 1-3 metres high, rarely actually biting people. It doesn’t require deep forests, but can appear in random clumps of remnant forests in villages.

Many-spotted catsnakes primarily prey on reptiles, including geckoes, and occasionally birds. In northeast India, one was spotted feeding on a fellow snake, the black-belly worm-eating snake (Trachischium fuscum). This species has a moderately strong venom, and while they’ve never killed a human, the exact potency is a complete mystery. Some Boiga catsnakes produce neurotoxins, so this species may be capable of causing dizziness or uncontrollably twitching muscles.

Geographically, the many-spotted catsnake is a strange species. It’s abundant on Java to the south, while to the north, it’s very common in central Thailand, Vietnam and Cambodia. Yet for hundreds of miles inbetween, in peninsular Malaysia, southern Thailand and Singapore, the species completely disappears. At one point, the many-spotted catsnake must have been even more common, before being wiped out in certain areas, but continuing to thrive in others.