Ben Madilynn
“This discovery fills us with hope,” says biologist María del Carmen Vizcaíno, director of the Alianza Jambato, a coalition of more than 26 institutions dedicated to amphibian conservation in Ecuador. Vizcaíno, who was not involved in the new study, believes that P. ruidus could become a “flag of resistance” in the legal fight to protect the southern Andes—Ecuador’s most degraded ecosystem due to mining and illegal logging.
Juan Carlos Sánchez (pictured here analyzing a museum specimen in the laboratory) and his colleagues compared the P. ruidis frogs to other species to confirm the rediscovery. Photograph by Jaime Culebras
Out of obscurity
In the 1970s, herpetologist John D. Lynch searched for and described several species from the southern Ecuador, but he never encountered P. ruidus. Instead, Lynch based his descriptions of the species on Tate’s preserved specimens, collected nearly fifty years earlier. In Sánchez-Nivicela’s laboratory at Universidad San Francisco in Quito, the team compared the wild frogs they collected to Lynch’s account.
The two frogs appeared just as Lynch had described and drawn them, with rough skin, many bumps and singular W-shaped ridges on their backs. Some frogs’ tympana or eardrums stick out from their heads, but not those P. ruidus—and neither did those of the wild frogs. “We went crazy,” Sánchez-Nivicela says. “It was perfect. The description matched perfectly.”
Researchers at the Universidad Técnica Particular de Loja also compared DNA from the two females with that of 35 other Pristimantis species preserved in a gene bank. The frogs’ genetic blueprint didn’t match any other species and confirmed the rediscovery. “It didn’t match anything because there was never any genetic material from this animal,” says Sánchez-Nivicela.
The rediscovery of P. ruidus is “a second chance to conserve what may potentially be the only locality where you can find it, not only in Ecuador but in the world,” says Diego Armijos Ojeda, a herpetologist at Universidad Técnica Particular de Loja. Armijos Ojeda was also part of an IUCN group that updated Ecuador’s Red List assessment of amphibian species in 2019, which showed that 363 amphibians are under threat—57 percent of the total species in the country.
