Experts from the Alfred Wegener Institute and the Universities of Oldenburg and Potsdam in Germany, have confirmed the existence of a new cryptic amphipod species in the North Sea.
Reports of new species in the North Sea often relates to animals or algae that have been introduced by human activities. Yet the discovery of a new amphipod species shows that there are still unknown organisms lurking in the German Bight. A team of scientists have discovered and described a previously overlooked species in the North Sea -- a rare event, considering that the region is one of the best-studied seas in the world.
The amphipod Epimeria cornigera has been known for a long time. Biologists have now discovered and descibed a new relative. (Photo: Alfred-Wegener-Institut)
Ecologist Dr. Jan Beermann From Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), and Michael Raupach from the University of Oldenburg analyzed so-called "DNA barcodes" of North Sea crustaceans: small genetic sequences that are a common tool in modern biodiversity research. Scientists create molecular libraries with these barcodes to simplify the identification of species. As Beermann and Raupach were analyzing the data, they began to wonder whether they were dealing with not only one, but two different species.
"Once we had a closer look we noticed that, for instance, some animals exhibited more pointed plates on their legs than others. But these subtle differences aren't always easy to detect," said Beermann. "The moment you realize that you've probably discovered a new species is fascinating and incredibly exciting. The North Sea isn't the first place you'd expect to stumble across an unknown species -- especially in a genus which is comparably large in the North Sea with a body length of up to three centimeters, and which eye-catching colorations have also attracted the attention of earlier generations of researchers."
The new Epimeria species was named Epimeria frankei, after Professor Heinz-Dieter Franke - an ecologist who worked for many years at the AWI marine station at Helgoland, and who was Jan Beermann's Ph.D. mentor.
With the discovery and the availability of extensive information on the two species, the researchers newly described both animals to include their genetic makeup. "In this regard, we wanted to prepare species descriptions that weren't restricted to the physical appearance but also include detailed genomic information," explains Raupach. "A few years ago, this would have been an extremely time-consuming. But nowadays, modern technologies make the analyses much faster and easier."
The discovered new amphipos species Epimeria frankei (below) and its known related species Epimeria cornigera (above). (Photo: Alfred-Wegener-Institut / Hermann Neumann, Senckenberg am Meer)
Scientists made use of the entire mitochondrial genome using state-of-the-art decoding methodologies, as well as cutting-edge technologies to sequence the genome in collaboration with the Genomics Team of Prof Michael Hofreiter from the University of Potsdam.
"We are the first team in the world to analyze the complete genetic material of the mitochondria, base pair by base pair, in the context of species description," says Hofreiter and Raupach.
The researchers were initially investigating Epimeria cornigera when they took notice of its sister species. Until then, Epimeria cornigera was commonly assumed to occur from the Mediterranean Sea to Iceland -- a quite broad but possible distribution. Nevertheless, reliable information on the species' biology was still scarce. As Beermann explains, "We now know that the new species, Epimeria frankei, ranges from the Mediterranean to the North Sea, whereas the old species, Epimeria cornigera, is more restricted to the northern North Atlantic. There is a small area of overlap in the North Sea where both species can be found." With the addition of E. frankei, there is now five known species of Epimeria in the north-eastern Atlantic.
Molecular methods have become an indispensable tool for modern biodiversity research. For their publication, the researchers combined various molecular genetics and morphological techniques to a so-called integrated taxonomic approach ("taxonomics").
The authors said, "The successful validation of this approach confirms that, for future biodiversity research, taxonomics could also prove to be extremely important for further considerations such as marine conservation."
This discovery also reminds us not to underestimate marine biodiversity, even in some of the world's most explored regions.