A rare species of frog that is native to the Bolivian Andes and is known for its translucent skin has been spotted in the South American country for the first time in 18 years, Newsweek reports.

Conservationists rediscovered the Bolivian Cochran frogs, more commonly known as “glass frogs” for their vitreous bellies that reveal their internal organs, on January 8 in the Carrasco National Park, near the central city of Cochabamba. The group was on an expedition in the area to rescue vulnerable reptiles and amphibians that face increased risk of endangerment due to an ongoing hydroelectric project.

“The rediscovery of this species fills us with a ray of hope for the future of the glass frogs — one of the most charismatic amphibians in the world — but also for other species,” members of the team told AFP news agency.

Photo by Matthieu Berroneau / Getty Images

According to Raw Story, glass frogs, which can be found in Central and South Americas, are very small, measuring only 0.7 to 0.9 inches and weighing about 2.5 to 2.8 ounces. The Bolivian Cochran frogs in particular are found in the departments of La Paz, Cochabamba, Santa Cruz and Chuquisaca; however, they haven’t been spotted in the regions for nearly two decades.

BBC reports that the team has taken the frogs to the K’ayra amphibian conservation center at the Alcide d’Orbigny museum, where they will attempt to breed the frogs as part of a conservation strategy. 

The tailless amphibians will join two other endangered water frogs, nicknamed Romeo and Juliet, that scientists have so far unsuccessfully been trying to mate in an effort to preserve them.