The discovery of a new species of frog was confirmed last week in New York City. The urban leopard frog, Rana kauffeldi, closely resembles the southern leopard frog, a species of leopard frog found in the same habitat. Because of this resemblance, the newly discovered species remained unnoticed until given away by its unique call.

Jeremy Feinberg of New Jersey’s Rutgers University is credited with discovering R. kauffeldi. He is familiar with the southern leopard frog and was able to identify the new frog’s chorus as something unusual in his study site on Staten Island.

“Frogs have very stereotyped calls within a species,” he said, “so I knew this was something different.”

Feinberg and other researchers describe the call as a “single-note unpulsed chuck,” which is, despite its uniqueness, often masked by the calls of spring peepers, which are small frogs common in the eastern United States and Canada.

It took two years for Feinberg to find geneticists to confirm his suspicion. When the tissues of the new discovery were tested, they confirmed that the frogs were members of a genetically distinct species.

R. kauffeldi represents a rare discovery, as the frog species of North America have been thoroughly documented. Feinberg reports that R. kauffeldi is “only the third new species of frog to be discovered north of Mexico since 1986.” It is also the first species of frog to be discovered in its region for almost three decades, according to BBC News.

The find is also unique in that it occurred in an urban area, albeit in a large tract of wetlands. Feinberg estimates that the R. kauffeldi species requires at least ten acres of wetland habitat. For now, this habitat is stable for the amphibian species that live on Staten Island. However, Feinberg cautioned that the species’ need for extensive and specific habitat in the midst of a developed area could put it at future risk.

“Elsewhere though, in places such as Madagascar, taxonomists and conservationists are racing against time to describe species before they become extinct,” said Dr. Gerardo Garcia of the UK’s Chester Zoo.

There are over 4,500 extant species of amphibians that have been documented at present, according to the Encyclopedia of Life, as well as many that are already extinct and an unknown number that have not yet been documented. One of the goals of ecologists is to move species from the latter category into the first — before they join the second.

Feinberg noted that the discovery of R. kauffeldi prior to the development of its current habitat for human use might protect the species.

“Imagine we moved forward 50 years and this frog had never been discovered. We might have destroyed its habitat and never known it was there. But this gives me hope that the species could be protected.”

Scientists continue to hope the same will hold true for other amphibian species across the globe not yet named.

“There is a huge backlog of species to describe,” Dr. Garcia said, “but sadly we’re late because the speed of extinction is faster than the capacity to protect them.”