Photo by Axel Marchelie

From October 4 to 23, we studied the richness and make-up of the herpo-fauna of the San Antonio Forest, documenting its diversity and conservation value.

Our team had high hopes with respect to this expedition since it is in a mountainous area whose herpetology is not well documented. We were sure that we would find some new species and encounter endemic species of the central Amazonia. Also, the rainy season was beginning in the area. This meant that amphibians would be more active and abundant since they reproduce at this time.

Photo by Axel Marchelie

Upon arriving, we went out at night to sample the heavily forested gorges which are closest to the town. We soon encountered species found in Peru’s central Amazonia, such as the toad Rhinella leptoscelis and the rain frogs Pristimantis ockendeni and P. Toftae, which were the most abundant. For three nights, we sampled around San Antonio where we looked for amphibians and reptiles in the riparian forests and slopes with pre-montane forests.

Our sampling in the San Antonio area was planned and coordinated with local residents. We established two camps for sampling at higher altitudes. Thus we could examine montane forests at elevations between 1700 and 2500 meters above sea level. We also selected well-forested land sloping down on both sides of the Pampa Hermosa River. In these places, we camped near water sources. There we found a couple of small living quarters at the edge of the forests. These magnificent camping spots were at 1400 meters and 1700 meters.

New frog species, photographed by Axel Marchelie

Beginning on the first day, we found some very interesting species. We had just begun setting up camp when we found a coral snake Micrurus annellatus and the lizard Euspondylus excelsum. This lizard was only described scientifically in 2017. At night we found other endemics such as the snake Dipsas schunkii and frogs such as Pristimantis bipunctatus. Surrounding this camp were steep slopes with well-preserved mountain forests. Torrents, which formed beautiful waterfalls, poured from the gorge and provided ample water.  As might be expected, there was an abundance of frogs. Here we found frogs of the genus Pristimantis, which were possibly undescribed, and a caracolera snake Dissas sp.

Photo by Axel Marchelie

We reached the highest elevation at our last camp. The geography was difficult. The mountain forest above 1800 meters is hard to walk in. It is very dense, and its soil is full of roots and moss. There was an abundance of frogs, such as Pristimantis cruciocularis in the highest part. This species is endemic to the forest of central Peru. We also found two new species of Pristimantis there, as well as reptiles such as the tree lizard Anolis boettgeri, another endemic to this portion of Amazonia. Still, another find was the spiny-tail lizard Stenocerus torquatus. However, the most impressive find was the tree toad Rhinella manu, which up until now has only been found in the montane forest of Manu National Park in Cusco. This is the first recorded find outside the national park.

Three weeks after returning from this productive expedition, we are relatively certain that we found 24 species of amphibians and 15 species of reptiles. We know that at least two of the frog species are new to science. We’ll continue working on our photos, field data, and preparing for future expeditions to this area, which is so rich in endemic species and so poorly known to science. We are also developing a plan to monitor the area. It is likely that, as we continue our research, we will find more new species and gather additional important scientific information.