Portugal: Lataste’s Viper

Portugal: Lataste's viper

Finding Vipera latastei...

I spent two months in Porto, Portugal from September to the end of October 2019. I had the fantastic opportunity to, not only, catch vipers in their natural hiding spots but also learn from skilled herpetologists and observe these animals very closely in the lab.ย  So here it is, enjoy my Portugal: Lataste’s viper article!

The camouflage of this species is quite spectacular, especially when the sunlight is making itself scarce.ย  Time of day and weather conditions are key elements influencing the probability of finding these out in the open. Starting sampling early in the morning when the sun is just starting to get warm is a good start especially when the wind isn’t blowing.

Look at this male that was released after a few days spent in the lab

It is unclear on whether the zigzag pattern of European vipers has an aposematic or cryptic function. The function of aposematism is a way of deterring and warning potential predators that the animal preyed upon can defend itself with poison or, in the viper’s case, venom. Crypsis, on the other hand, is the animal’s ability to avoid detection and hide with a morphological camouflage (1).

Lataste's viper is sexually dimorphic in terms of colour & size

Males are smaller and have a more contrasted dark pattern and females are larger and lighter in coloration (see photos below).

Venom Toxicity

Venom toxicity depends on many different factors. However, the venom of Vipera latastei is known to have necrotic effects with reported deaths in the past. Children, elderly and allergic subjects are most at risk of aggravated symptoms. The venom contains hemotoxins which disrupt blood clotting and may cause organ degeneration and tissue damage locally.

Other effects of the bite include swelling, discoloration and pain. Venom colour is commonly yellow, although it has been observed to be sometimes transparent (reason is unknown but research is ongoing).

Lab Work & Observations

Heads Up: If you're scrolling on your phone better to take the laptop out to really appreciate these animals in full extent!

The venom of latastei only regenerates after 15 days which makes venom sampling a delicate task.

Careful handling of the viper when caught in the field and during milking is vital. If it defends itself and attempts to bite, collecting the venom will be trickier as the amount will be deminished. Also, the aim is to keep the species in the lab as little time as possible.

The viper has continuously regenerating fangs, which are vital to their survival.

When biting into a prey a fang may find itself lodged into it and found later in the viper’s excrement (when prey was swallowed). For instance, when milking a viper, one of the fangs may fall.

Vipera latastei gestation period is of approximately 3 months with labour usually lasting between 2 or 3 hours. However, in lab conditions, it was observed to last up to 2 days.

Up to an amazing 17 babies were born from a single female!

female lataste's viper

My first ever caught female viper (September 2019)