New 'coffee frog' species discovered in Costa Rica's coffee highlands
Researchers from Costa Rica and Argentina have identified a new tree frog species in San Lorenzo de Tarrazú, Costa Rica. The tiny amphibian, under 4 cm long, lives among coffee plants but faces risks from plantation pesticides.
Discovery in the coffee highlands
Researchers have identified a new species of tree frog in San Lorenzo de Tarrazú, a mountain village in the province of San José, Costa Rica. The amphibian is minuscule, nocturnal and greenish in colour, measuring less than four centimetres in body length, with dark green spots covering its body. AFP reporters observed the frogs on site in the Tarrazú district, located in Costa Rica's central Pacific region. Wagner Chaves-Acuna, one of the researchers responsible for the study, confirmed the finding in comments to the agency, citing the conclusions of colleagues at the University of Costa Rica and Argentina's National Council for Scientific and Technical Research.
The species is endemic to Costa Rica, meaning it has been found nowhere else. Chaves-Acuna described it as a new tree frog species for science, based on the joint research conducted by the two institutions. The study was led by the University of Costa Rica and the Argentine research council, with Chaves-Acuna presenting the findings to AFP.
A frog named for coffee
The species has been nicknamed "coffee frog" (grenouille du café) because it finds its ideal habitat among coffee plants. It has also been referred to as "spring frog" (grenouille des sources) in French-language reporting. The frogs are nocturnal and reach their peak activity after dark, when males perch on coffee bushes and produce their distinctive calls.
At night, when they are most active, you can hear them singing while perched on the coffee bushes.
The frogs seek shade, moisture and food within the coffee crops, but they do not feed on coffee cherries. Instead, they prey on the small insects present in the habitat. Specimens have also been found in areas distant from the coffee plantations, indicating the species is not exclusively dependent on cultivated land for survival.
A distinctive call
Males of the species possess a translucent throat that swells visibly when they emit their call, which is described as brief and high-pitched. This characteristic, along with the frog's small size and dark green spotting, distinguishes it from other known tree frogs in the region. The frogs were observed in San Lorenzo de Tarrazú, a mountain community in Costa Rica's central Pacific area known for coffee cultivation.
Pesticide risk
Chaves-Acuna warned that the coffee plantations providing habitat for the frogs could also endanger them through the use of pesticides and other agrochemicals applied to protect the crops. The researcher outlined a specific pathway of exposure for the amphibians, though no study has yet confirmed the extent of the risk to the species.
These poisons spread through the air... they infiltrate the soil and from there enter the aquatic systems where the tadpoles develop.
The toxins can travel through the air, seep into the soil, and ultimately reach the water systems where tadpole development takes place. The impact of these agrochemicals on the newly discovered species remains unconfirmed by any study to date.
