Massive Herpetofauna Discovery in Maramena, Greece
A new paper published in Palaeontologia Electronica (PE) describes the most diverse assemblage of amphibians and reptiles ever preserved in Europe across the Miocene-Pliocene boundary. Herpetology is the study of reptiles and amphibians where herpetofauna refers to the reptiles and amphibians of a particular habitat, region, or period in geologic time.
Dr. Georgios L. Georgalis (University of Torino) studies fossil herpetofaunas and described this bountiful discovery from the Neogene of Maramena, Greece, along with his colleagues from German, Czech, and Swiss Universities. More specifically, these fossils span the late Miocene to early Pliocene boundary just over five million years ago when the European continent experienced several climatic and environmental shifts. Herpetofaunas naturally are very sensitive to such changes and suffered extinctions to several clades across the region during this time.
“During that time, there is observed a relative impoverishment of European herpetofaunas, in comparison with those present in the continent during the early and middle Miocene. Accordingly, the identification of at least 30 different species of frogs, salamanders, turtles, lizards, and snakes in a single locality of that age appears rather surprising, taking also into consideration that such number surpasses by far any other coeval herpetofauna” says Dr. Georgalis.
Traditionally, mammals are the focus of study from Cenozoic deposits, which makes this locality even more unique. “As a matter of fact, large mammal remains are more easily recovered and identified in fossil localities, in comparison with tiny, fragile lizard jaws or snake vertebrae” says Dr. Georgalis.
This amazing diversity can be partly explained by a distinctive region-wide event. “The Messinian Salinity Crisis, when large portions of the Mediterranean Sea dried out, facilitated potential dispersals of vertebrate groups from Africa to southern Europe; on the other hand, however, several species from Maramena have their closest relatives in much older localities from Central Europe”.
Being able to study herpetofaunas, provides an in-depth look at what the environment was like at the time.
“They are much more reliable indicators of palaeoclimate and palaeotemperature in comparison with sympatric mammals and they have been continuously used as such in various palaeoclimatic reconstructions over the past decades. As for the Maramena locality, the identification of thermophilous reptiles such as cobras and monitor lizards, imply a warmer climate” explains Dr. Georgalis.
It seems to have been the perfect conditions to corral a bunch of water dependent fauna in the same place. “This discovery represents the earliest regional occurrence of several extant genera of amphibians and reptiles that are currently present in the area and records several other groups, including giant salamanders (Cryptobranchidae) from the Eastern Mediterranean for the very first time” explains Dr. Georgalis.
“This area probably acted as a kind of “refugium” for several amphibian and reptile groups that had otherwise become extinct in northern parts of the continent.”
Out of all the diverse forms present, Dr. Georgalis’s favorite were the two new snake species.
“Snakes are the most diverse group in the Maramena herpetofauna, comprising at least 10 different species. Among them two represent new genera and species, Periergophis micros and Paraxenophis spanios, as they are characterized by rather distinct vertebral morphology with features unknown in other extinct and modern snakes” shares Dr. Georgalis.
For such a massive discovery, I have a feeling there is much yet to uncover for both these species and the locality itself.
To read more about these findings you can read the original article here.