A new three-fingered frog species (See photo) has been discovered in a rainforest reserve in southern Brazil.

Researcher Michel Garey found the new species (Brachycephalus tridactylus) in 2007, but it was officially recognized only this week. The findings of the study are published in the journal Herpetologica.

"I was doing research with two friends on a hilltop in the reserve and I stumbled into this unusual frog with only three fingers," Garey told reporters this week on a tour of Salto Morato Nature Preserve in Brazil.

"It happened on February 14, 2007: My birthday. What a treat!" he said.

The new species, Brachycephalus tridactylus, measures just about 0.5 inches long (1.5 centimeters). Garey found the species at an altitude of around 3,000 feet. They are mostly in orange color with olive-gray spots and dots on its body, an Agence France-Presse report said.

Garey said that the frogs have three fingers instead of four, as part of the evolution and not because of any environmental effects. He also noted that the male frog makes around 30 mating calls every day, which he describes as "a single short note that decreases in dominant frequency from beginning to end."

The new frog species is one of the 43 amphibian species found in the Salto Morato Nature Preserve, which is considered a haven for scientists to study the diminishing Atlantic rainforests.

The natural preserve is biologically diverse and is home to around 2,200 species including birds, fish, reptiles and amphibians. It also houses 60 percent of all of Brazil's threatened animal species, the AFP report said.

Climate change is posing a major threat to the survival of amphibians across the globe. According to reports from Global Amphibian Assessment, one-third of the known species of frogs are facing the risk of extinction.

Frogs' skin is permeable and hence they are prone to ultra-violet radiation and their body temperatures change with unpredictable shifts in temperature, said Garey.  The immune system of the frogs seems to lose strength with temperature shifts.

He suggested that it is very important to understand the frogs' life cycle (they live both on land and in water) as they can serve as "bioindicators of environmental quality."