The Nubian spitting cobra pictured by Dr Wolfgang W�ster

A number of the reptiles - a previously unknown type of spitting cobra - were handed in to London Zoo after being confiscated by police investigating illegally traded pets.

Staff at the zoo did not recognise them and called in Dr Wolfgang W�ster, from Bangor University's School of Biological Sciences.

He said the markings on the snakes were similar to those seen on cobras found in Egypt and the Sudan, an area once called Nubia.

The snakes have now been classified as naja nubiae or Nubian spitting cobras.

Zoo keepers originally thought that they might have been red spitting cobras, but further examination ruled this out.

Dr W�ster - who has, in the past, been involved in the identification of three other mystery snake species - agreed with keepers at the zoo that the snakes were different to any already identified.

Dr W�ster confirmed his suspicions by carring out DNA testing on sample of scale.

The snakes were handed over to London Zoo as part of an illegal pet trade confiscation, so it is still not clear from where they originated.

Working with fellow reptiles experts, Dr W�ster narrowed down the areas to specific parts of Egypt, the Sudan, Chad, Niger and Eritrea.

Experts at first thought it was a red spitting cobra

As the majority of documented specimens came from southern Egypt and the Sudan - an area once called Nubia - they have now been classified as naja nubiae or Nubian spitting cobras.

The snakes are still at London Zoo, and have bred since being there.

"More work now needs to be done to establish a few facts about this species," said Dr W�ster, who is who lectures in zoology and is an expert in reptile taxonomy or species identification, and the evolution of venom in snakes.

"We have established that they come from densely populated fertile lands in the Nile valley, so for conservation reasons, we need to establish how large the population is , over what areas they are scattered, and whether they are endangered.

"As they live so close to areas of human habitation, we also need to test their venom to see if it is compatible with anti-venoms that are administered for other cobra species in the region.

"Venom can vary between different species of cobra, or even within a single species."

Terry March, from the Reptiles House at London Zoo said his team was delighted to have played a part in discovering a new species.

And, he added : "To then see the snakes successfully breed makes it even more significant as there is so little known about the species and much too learn."