Fan-Si-Pan Horned Pit Viper - Protobothrops Cornutus

 Protobothrops cornutus, commonly known as the Fan-Si-Pan horned pitviper, is a venomous pit viper species endemic to Vietnam. Previously, it had been known from only two specimens, but was recently rediscovered in the central part of the country. No subspecies are currently recognized.

Fan-Si-Pan Horned Pit Viper

Kingdom	Animalia
Phylum	Chordata
Class	Reptilia
Order	Squamata
Suborder	Serpentes
Family	Viperidae
Genus	Protobothrops
Species	P. cornutus
Scientific Name	Protobothrops cornutus

Although species of these ‘Prototype Bothrops’ are not nearly as generally kept as other Asian pit vipers like animals from the Trimeresurus species, Protobothrops cornutus is one of the more ‘common’ species of the Genus in captivity. This probably has to do with the fact some zoological but also private keepers have relatively good success with breeding this species and they seem to do well in captivity and under certain circumstances.

Before you consider keeping these species, there has been very little research done on venom of these snakes, there is no specific antivenin and although not considered to have a very strong venom. Every person can react differently to a bite and every accident must be taken very serious. Please note that keeping a venomous snakes comes with great responsibility towards yourself, the snake and others. In general we advise against keeping these animals but understand some people are experienced and knowledgeable enough to do so in a safe manner.

Description

Fan-Si-Pan Horned Pit Viper is a relatively small semi-arboreal pit viper that grows too almost 70cm. They are slender and agile. The head is clearly distinct from the neck, it has a reasonably flat top and viewed from above it is clearly triangular shaped. They have big eyes, one of the features of a clearly nocturnal hunter. Above the eyes they have several raised (normally 2) scales giving them their common name the ‘horned pitviper’. But common names like these can be confusing as more snake species have horns. They have a pale tongue. Pictures attrached to this sheet give a good representation of the colour and pattern of these species. You could call their colours and pattern cryptic, quickly observed certainly not as strikingly coloured as the greens of Trimeresurus sp. This appearance serves them well as camouflage against the rocks and forest floor they reside. Scales are keeled. Between localities the colour may differ a bit. While individuals from the Quang Binh provice have more brows, greens and yellows the animals from QuangDong seem to be paler/lighter.

Behaviour

These are almost fully nocturnal and by day will hide in holes, under logs and for most between cracks and in caves in the karstregions which is their preferred habitat. When the sun goes down they become active and will move about. They can hunt prey but prefer to be a true ambush-hunter. Positioning themselves on a small branch or against a tree, just in striking distance of the ground they will wait until a prey will pass. They strike, often let go and will look for the prey after a few minutes. In captivity young will mostly strike and hold one but adults often strike and let go. This may have to do with the type of prey that is fed on depending on the age and size of the snake, not forgetting the season certain preyitems are more active as others.

In captivity they seem to be alert snakes, clearly active during the night. When disturbed they will go in a defensive position fast and react very alert to movement and touch. They are not tend to strike toward this movement unless it has a clear heat signature but will strike aggressively when disturbed to much. They are fast strikers and a bit more ‘calculated’. They will defend themselves when feeling threatened.

Feeding

In nature these snakes mostly feed on frogs, some small rodents and sometimes a lizard. This means especially young can be reluctant feeding on the typical pinky mouse. These young are hatching while young frogs are abundant so will feed on that during the first period of their life. We could also feed hatchlings with frogs but this can be costly, impractical and wildcaught frogs can be carrying several parasites. To increase the change of a positive feeding response, make sure temperatures are above 17C. Also feed when the lights are off, only a general light in the room as we want to keep it safe with working with these venomous snakes. U can start trying with a life pinky mouse, possibly scented with a frog. Teasefeeding, using a thawed and warm pinky mouse on the end of tweezers. Try to aggravate the snake by bumping the mouse against the tail or body hoping for a biting response. It might take a few tries but when the snake bites and hold on. Gently let go and sit perfectly still not to disturb the snake. Then it can go two ways, ether the snake drops it, or they will start swallowing.

As adults they seem to be more strike and let go hunters. Especially when we feed with live rodents. Feeding can be on a frequency of ones every 2 weeks. They can take relatively large prey compared to their body but a good sized prey items are subadult mouse or young of other regular kept rodents.