A new paper in the journal Nature Communications proudly marks the rediscovery of a piece of paleontology that is – despite all expectations – still alive. Authors Rebecca Biton of the Hebrew University of Jerusalem and Eli Geffen of Televiv University and their associates report that the extinct Hula frog, an amphibian who’s only known habitat is the Hula Valley of Israel, might have a second chance.
The swamps and shallow lakes of Hula Valley only covered about 37 square miles, but were a virtual paradise for freshwater plants, crustaceous, fish, shellfish, migratory birds, and amphibians. All of that changed in the 1950s when the valley was drained to create more farmable land.
As the muds dried up so did the unique ecosystem. Among the casualties was the Hula frog which was declared extinct in 1996 after no one had seen it for sixty years.
Then, on November 15, 2011, a park ranger peering through the swamps of the mile long Hula Valley Wildlife Preserve sighted a distinctive creature: a medium sized frog, red or ocher colored on top and black on the bottom with white spots on its belly. Discoglossus nigriventer, the Hula frog, had returned.
However, this wasn’t the only surprise it had in store for scientists. Previous to 1950 D. nigriventer had already been an elusive species. Only two adult specimens and two tadpole specimens had ever been collected. Biologists assumed the frogs were indeed from the genus Discoglossus, a member of the Discoglossidae family of amphibians that is common to the area.
With the help of the newly discovered living specimens Biton and Geffen were able to better classify the new species. While, at first blush, the Hula frog looked very much like the painted frogs of Africa, genetics and CT scans were able to verify it had a lot more in common with dead frogs than with living.
The genus Latonia is also part of the Discoglossidae family, but for thousands of years it has only existed in the fossil record. Species of the Latonia genus were widespread across Europe during the Oligocene and Pliocene epochs. The entire genus seems to have died out by the early Pliocene.
Using these fossilized frogs, Biton and Geffen were able to verify that the Hula frog doesn’t just represent a species that has been thought extinct for sixty years. It also represents a genus that has been thought extinct for 15,000 years.
“Nobody ever had a chance to see a Latonia because it went extinct in Europe. The only way anyone could see it was through looking at fossils,” says Professor Sarig Gafny, an expert in river ecology from the Ruppin Academic Center in Israel. “But then with every characteristic that you look at in the current Hula painted frogs, it matches that of the fossils of Latonia and not that of the Discoglossus. So this is a living fossil.”
The reappearance of the Hula frog is significant on a symbolic level as well. It was the first amphibian the International Union for Conservation of Nature, or IUCN, declared to be extinct. It reappeared after steps were taken to repair some of the ecological damage done to the Hula Valley by re-flooding more land.
The damage caused by draining the swampland can never fully be undone, but Israel’s efforts are already paying off in a big way. Several species of aquatic plant have already been restored along with fish, shellfish, and other mud and water dwelling critters. Migratory birds are again stopping by on their way from Europe to Africa, restoring the Hula Valley a little of its former glory.
The return of the Hula frog, now known as Latonia nigriventer, is as astounding a triumph for the valley and for the efforts of conservationists as it is for paleontologists. While still listed by the IUCN as “critically endangered” the ten specimens found in the wild since 2011 indicate that it still has a fighting chance for survival. This is hopeful news as the IUCN still lists 34 species of amphibians as extinct and 122 more haven’t been spotted in decades.
Find the June 4, 2013 study in the journal Nature Communications.
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