An international team of researchers has identified a new species of grass snake in England, UK. After identification of this new barred grass snake, the number of grass snakes species in the UK has increased to four.

Grass snakes are among the most common snakes found in the UK as well as in whole Europe. They are non-poisonous and are identified by their olive green body. They can grow more than 3 feet in length; females are generally longer than males. They also have dark spots on their flanks. They prefer to live near ponds or rivers and survive on frogs, newts and toads.

These snakes are often confused with slow worms (legless lizards), which are much smaller. Despite being found in large numbers in Europe, scientists have very little information about the genetic identity of these reptiles.

Scientific name of new snake species is Natrix Helvetica

With the identification of new barred snake, scientifically named Natrix Helvetica, the total grass snake species found in the UK has increased to four. The other three snakes found in the UK are: (1) The smooth snake (Coronella austriaca), (2) Adder (Vipera berus), and (3) the eastern grass snake (Natrix natrix). Of these, only the adder (with a thick-set body and vertically slit pupil) is poisonous, while the smooth snake is rarely seen.

According to scientists, the newly identified barred snake is widely distributed throughout Switzerland, Great Britain, France, Italy, and western Germany. It lacks the striking bright yellow collar and is grayer compared to its olive green relative. The dark bands along its body are more pronounced than the bands of the common grass snake.

Researchers analyzed genetic identity of over 1,600 snakes

In this study, the international team of researchers, led by Professor Uwe Fritz, from the Senckenberg Research Institute in Germany, focused on two areas where different genetic lineages of the grass snakes meet. Of these two zones, one lies in Rhine region, while the other extends from Central Germany to south Balkans.

According to researchers, such zones are natural labs for evolution and allow the study of speciation and hybridization. The team analyzed the genetic identity of no less than 1,600 grass snakes, including those kept a scientific specimen in museums. The results suggested that the barred grass snake that was earlier considered a subspecies was actually a separate species.

Scientists also observed that the hybrid zone in the Rhine region — less than 50 km wide — exhibited only limited and unidirectional admixture. The second hybrid zone however extended over hundreds of miles and exhibiting a complete mixing of the involved genetic lineages.

The detailed results of the study have been published in the journal Scientific Reports.