| 1 | Dumeril’s boa |
The most common boa in southern Madagascar. Dumeril’s boa is a popular species in captivity worldwide, and has a strange similarity to the boa constrictor, despite living halfway across the world from each other. This is a tank of a snake which stays on the ground most of the time, waiting in ambush, using its immense camouflage to blend into leaves. They also shelter in hollow logs. Dumeril’s boas prefer drier woods and more open forests. Younglings climb trees, before becoming so bulky that the branches are at risk of snapping.
Dumeril’s boas mostly prey on mammals, one confirmed being the southern bamboo lemur. Newborns average at 45cm and by adulthood, they grow to a brutish 2.5 metres, the record being 259cm. Dumeril’s boa also inhabits caves, including in Madagascar’s Tsimanampesotse National Park, which they turn into a permanent base.
For years, Dumeril’s boas were exported en masse from Madagascar, and their numbers in the wild are now far lower than originally. Dumeril’s boas are hunted by locals for food and to turn into handbags, and deforestation is rife on Madagascar as well. Fortunately, there’s plenty of captive breeding operations overseas, including in southern England’s Cotswold Wildlife Park.
| 2 | Common Madagascar cat snake |
A nimble tree snake found only on Madagascar. Madagascarophis colubrinus appears anywhere where trees grow, including woods and remote forests, but also public parks and gardens. There’s a great mystery over exactly how venomous the Madagascan cat-eyed snake is. They secrete a venom from their rear fangs, rather than two needle fangs like cobra. These are usually weak, but bites have been reported to cause swelling, pain, blistering and necrosis. Others report that the bite is near harmless in humans, and is so weak in its prey (which includes chameleons and hatchling birds) that they have to deploy constriction as a back up.
Deepening the mystery, a 2023 study discovered that Madagascarophis colubrinus venom contains a neurotoxic peptide called macoluxin, which binds to acetylcholine receptors in muscle cells. These are the same receptors that black mamba neurotoxins bind to, in order to cause paralysis and laboured breathing.
This species is the most common of the 5-member Madagascarophis family, collectively called the Malagasy cat-eyed snakes, which are found nowhere outside their namesake island. This common snake has consistent blotchy patterns, but their colours vary from yellow to brown to silver. They live in every corner of Madagascar.
| 3 | Madagascan ground boa |
The longest snake on Madagascar, reaching a maximum of 320cm. This belongs to the same family as Dumeril’s boa, but controls the north and northwest, while Dumeril’s boa controls the south. Madagascan ground boas live in dry, open woodlands, and their camouflage is just as excellent as their cousin. Camouflaged eyes are a classic feature of this snake family – the brown stripe on their face continues right through the eye uninterrupted.
This snake mainly eats mammals, such as brown lemurs and Coquerel’s sifakas. In captivity, they happily swallow birds as well. Madagascan ground boas are shy and mainly stick to the ground. They’re not especially aggressive with humans, and reproduce slowly, laying 2-4 live young after a long gestation period of 4-6 months.
This species also produced the heaviest Madagascan snake yet recorded. “Big George” was measured on July 2nd 2013, and weighed 8.2kg, with a length of 270cm. It lived in Anjajavy l’Hôtel, Sofia Region, northwest Madagascar, where it had inhabited the grounds for years (since 2004) and was a familiar character to the staff.
| 4 | Tiny night snake |
Ithycyphus miniatus, AKA the tiny night snake, is a small species which is misleadingly named, as it actually moves by day. This snake lives only on Madagascar, mainly in the northern half, and splits its time between low branches and the ground. Tiny night snakes vary from reddish-brown to a tree branch beige, which allows it to blend perfectly with its forested habitats. They get darker as they approach the tail, often beginning beige and ending red.
This species has two detailed bite reports in humans. The first involved a 33 year old man who dislodged the snake after 30 seconds, and no symptoms appeared whatsoever. But the second man (aged 42) was worried about the snake’s teeth slashing his finger, and so left it attached for 60 seconds, in which it chewed nonstop. The man’s finger swelled enormously, followed by his hand at the base of the finger, followed by the middle finger and little finger.
He also reported a low appetite later that evening. Scientists have also noticed how its prey (which includes panther chameleons) becomes immobile after being bitten. The verdict: this Madagascan snake has a slight chance of sending a human to hospital.
| 5 | Giant Madagascan hognose snake |
On Madagascar this snake is called Menarana, while the Dutch call it Madagaskar haakneusslang. Madagascan hognose snakes (Leioheterodon madagascariensis) measure 1.5-1.8 metres and have a mild rear-fanged venom. This is one of the most common, successful species in Madagascar, and hasn’t slipped into vulnerable status like the boas.
Madagascan hognose snakes are flexible and can be found slithering through villages or even on the outskirts of cities. Dry plains and woodlands are equally acceptable to them. They spend most of their time on the ground, climbing low branches very occasionally.
This is a snake which never gives up; they defend their own egg nests aggressively and will wrestle each other for mating rights. If they meet humans though, they usually flee, or perform a bluff strike, rarely ever biting. This is one of the most confident Madagascan snakes and will slither around happily, making no attempt to disguise themselves. Leioheterodon madagascariensis is black and cream coloured, but the exact proportions vary. Some alternate in evenly spaced checkers, but others have a fully black body with a cream belly.
| 6 | Pencil snake |
This snake looks like a piece of tree bark which started slithering. Pencil snakes measure 75cm at most, and almost never bite humans. This snake mainly sticks to the ground, sometimes climbing to low branches. They can reach very high densities and are infamous for hanging out in bushes at night in large numbers.
Pencil snakes inhabit virtually all of Madagascar, except the humid east coast. Though they eat frogs and other snakes, this species particularly likes chameleons, including southern carpet chameleons, canopy chameleons and Labord’s chameleons. Pencil snakes don’t shy away from human zones either. Dry woods, thorn forests and savannahs are some of their favourite natural habitats. This snake has a mild venom which it chews into prey to disable them, which causes little more than itching and a mild throbbing pain in humans.
Originally, Mimophis mahfalensis covered the whole of Madagascar. In 2017, the northern enclaves were split into a new species: Mimophis occultus. These are the only two members of the Mimophis family.
| 7 | Madagascan tree boa |
This boa belongs to a different family: Sanzinia, of which it’s one of two members. This species averages at 122-152cm, and mainly lives in Madagascar’s north, northwest and east.
The name is misleading, as this species splits its time between branches and the forest floor. They’re nocturnal, and rest on branches during the day, before waking up, dropping to the ground, and starting their nightlong quest for mammals, their main prey. Sanzinia madagascariensis are common in forests, but also villages, where they take advantage of the legions of introduced black rats and Norwegian rats. During sunny weather, Madagascan tree boas form a compact ball at the junction of a branch, to bask in the warmth.
At a maximum of 213cm, this species is the shortest of the three Madagascan boas. But they have an advantage too: heat-seeking pits in their face, which grant them infrared vision at night, which Dumeril’s boa and Madagascan ground boa lack.
This snake has hourglass or flower shaped markings, bordered by snowy white patches. When pregnant, female Madagascan tree boas grow steadily darker, in order to absorb more warmth for their developing young. These arrive in batches of up to 12, and measure 38cm on day 1.
| 8 | Lateral water snake |
This species is like the garter snake of Madagascar. It averages at 90cm, and preys mainly on amphibians. They’re ground dwelling, but spend a large portion of time in streams swimming peacefully. They even look similar, with a thin head and parallel beige stripes on each flank.
This is an extremely common species in Madagascar, including in rainforests, rice fields, grasslands and secondary forests. Lateral water snakes have the rare skill of eating poisonous Madagascan frogs, such as the Golden mantella. This has bright orange colours to warn predators of its danger, and is reputed to taste disgusting thanks to alkaloids in its skin. Thamnosophis lateralis doesn’t care, and can eat them anyway, as spotted in 2007.
Though small and humble, lateral watersnakes have a nervous temperament, and will bite humans readily if agitated. Their first defensive display is to flatten their necks, making themselves larger. Lateral watersnakes have white skin, which becomes visible through their black scales with this flattening. There’s also electric blue patches occasionally visible.
| 9 | Slender smooth snake |
The Liopholidophis family has 8 members, all found exclusively in Madagascar, and all shy and harmless. Slender smooth snakes (Liopholidophis rhadinaea) are recognisable by their bright pink bellies the colour of candy floss. This snake has an extremely large gender size discrepancy. The record length in males is 74.9cm, already pretty modest, but in females the record is just 42.4cm. Much of this is down to the tail, which measures 37-43% of the body in males versus 24-27% in females. This tail itself is another record, being one of the longest of any snake.
Slender smooth snakes live in dense forests with a closed canopy. They have very complex patterns, with black lines, beige stripes, a parched brown head, and a creamy chin intermingling. They’re completely harmless to scoop up in your hands and admire, if you can find them.
This Madagascar snake has the power of “tonic immobility“, when snakes instantly paralyse themselves to convince a hungry predator that they’re dead. This is activated usually after touch. In the Liopholidophis family, slender smooth snakes are the only one known to go completely still like this.
| 10 | Bernier’s striped snake |
An energetic snake which raises its neck and scans the horizon keenly for prey. This is a fast-moving snake measuring 70-90cm, with an absolute maximum of 117cm. This species is found in almost all of Madagascar, from north to south. Bernier’s striped snake preys almost completely on lizards, with the occasional frog being ingested such as Douliot’s bright-eyed frogs.
This snake likes to move in the midst of dry grass, strewn with fallen twigs and branches. Their striped patterns are perfect for camouflage there, just as a Dumeril’s boa is specialised for camouflage in leaves. However, they also move through open dirt roads and sandy plains. In northwest Madagascar, this snake is called “Maro longo”, which translates to many friends. This is because many males chase a single female at once, and eventually dogpile them.
Female Bernier’s striped snakes are longer than males by about 20cm. This species is also eaten by other snakes, including Madagascan black-backed smooth snakes.