Crytptic New Species of Leopard Frog Found in New York City

For a field-based ecologist, the continental United States is pretty much a textbook of well-known organisms. The thrilling new species often making front-page news are more likely to found in the tropics or open-oceans, than in the plains of the Midwest or the large metropolis cities of the East and West coasts. With such well-defined niche habitats, the species in the United States aren't too surprising to the experienced biologist, however, sometimes new life can be found where you'd least expect it. No, we're not talking about the mutant turtles in the sewers of New York City, but it does appear the jam-packed hub may be home to another unique amphibian, colloquially known as the "Atlantic Coast Leopard Frog".

It's quite an unexpected discovery in the realm of science, that amidst the hustle and bustle of New York City, researchers are still able to identify new species. But that's exactly what Brooklyn-based ecologist, Jeremy Feinberg has done.

The species, more scientifically named Rana kauffeldi was first identified by Feinberg six years ago as part of his PhD thesis. In the early spring, Feinberg made a trip to Staten Island in search of males singing their mating song, and what he heard was a new call not known to science. It was a distinct call, but it wasn't the call of the southern leopard frogs he had gone out there to research.

"Probably within 10 seconds my friend and I were both like, 'Are you hearing that?'" Feinberg said. "We knew they were leopard frogs, but the call was way off."

While the researcher didn't initially know he was on the trail of an entirely new leopard frog species, after significant genetic analysis, Feinberg realized he had made the discovery of a lifetime... all in the middle of one of the largest metropolis cities on Earth.

To be fair to Feinberg, the species he discovered is known as a "cryptic species", because it looks nearly identical to the southern leopard frog. But the two differ in distinct ways. Scientists now know that the two have slightly different spatial pattern arrangements on their hind legs, but more importantly is the distinct mating call Feinberg first heard. The small pauses and unique rhythmic croaking make the two species separate without the possibility for interbreeding in spite of their relatively similar appearances.

Publishing a new paper in the journal PLOS One this week, Feinberg and his colleagues are the first to give a detailed examination of the amphibian's call, morphology and range. And the researchers have discovered exactly what makes Rana kauffeldi unique amongst its dopplegangers.

"In diagnosing, describing, and defining the Atlantic Coast leopard frog, we add a new and potentially at-risk cryptic vertebrate species to the northeastern and mid-Atlantic US fauna" Feinberg says. "Rana kauffeldi can be characterized as potentially vulnerable with highly specialized and restrictive habitat needs, locally abundant where present, having a restricted distribution across heavily populated urbanized regions, and having suffered extirpations from certain areas."

"Concerns over habitat loss and degradation continue today, along with a suite of other threats (e.g. disease and contaminants) that may pose additional future challenges [to the cryptic species]."