22nd February 2016: Europe has gained another snake
New species of grass snake discovered
Dresden, 22 February 2016. In collaboration with an international team, scientists of the Senckenberg Natural History Collections in Dresden have identified a new species of snake in Europe. In an integrative study, published today in the Biological Journal of the Linnean Society, the researchers were able to demonstrate that the Iberian Grass Snake does not constitute a subspecies of the wide-spread common Grass Snake as previously thought, but rather a distinct species.
The Grass Snake is widely distributed across Europe and Asia; in many countries, this harmless reptile with the characteristic, pale crescent around the neck is among the most commonly encountered snakes. “It may well be due to this abundance that there are so many different views regarding their taxonomy”, says Professor Dr Uwe Fritz, Director of the Senckenberg Natural History Collections in Dresden, and he continues, “Depending on the author, the number of recognized subspecies ranges from 4 to 14.”
In cooperation with the PhD student Carolin Kindler, colleagues from the Zoological Research Museum Alexander Koenig in Bonn and additional international partners, Fritz now discovered that the Iberian Grass Snake – previously considered a subspecies of the common Grass Snake – is in fact a distinct species. “Europe’s vertebrates are generally well-studied – the discovery of an additional species is therefore quite remarkable”, underlines a delighted Kindler.
The team of scientists used various methods to study more than 300 snakes from different museum collections and combined this data set with genetic data of 85 Grass Snakes. “We connected external morphology, such as scale numbers, with characteristics of the skeleton and genetic features; and based on these results, we found out that the Iberian Grass Snake – Natrix astreptophora – constitutes a full species,” explains Fritz.
The genetic studies also show that the newly discovered species does not share its habitat with the common Grass Snake Natrix natrix, whose subspecies are widely distributed throughout Europe and Asia. Natrix astreptophora occurs in the North African Maghreb region, on the Iberian Peninsula and in Southern France. Kindler explains, “the two species only meet in the south of France, near the Pyrenees. But there is virtually no hybridization between the two species in this region – “strong evidence that Natrix astreptophora constitutes a separate species,” adds Fritz.
As a hunter of amphibians and other small animals, the common Grass Snake, which can reach a length up to 150 centimeters, is tied to wet habitats – and these are increasingly threatened by the draining of wetlands, the regulation of river courses and the intensification of fish farming. The Iberian Grass Snake, however, is much less dependent on the presence of water than its wide-spread relative. Many grass snakes fall victim to automobile traffic; around some of the larger lakes, tourism poses yet another threat to the grass snakes. “The knowledge about which species we are dealing with helps us to better assess the threat level and to implement timely protection measures. This is of particular importance, since the Iberian Grass Snake prefers different types of habitat,” adds Kindler in summary.
Pokrant, F., Kindler, C., Ivanov, M., Cheylan, M., Geniez, P., Böhme, W., and Fritz, U. (2015). Integrative taxonomy provides evidence for the species status of the Ibero-Maghrebian grass snake Natrix astreptophora. Biological Journal of the Linnean Society.