The Atlantic Forest takes a lot of space in my heart. Its biodiversity has always fascinated me, especially the fauna. As it is impossible to work with all groups of animals, I had to prioritize a group and without much difficulty, I chose Herpetofauna. This scientific field worries about almost 12,000 species of reptiles and about 8,000 species of amphibians according to the most used databases in the world (Reptile Database and Amphibians Species of the World respectively). These species are grouped into several taxonomic categories we call orders. Among reptiles, we have Crocodilians (alligators and crocodiles), Squamates (amphisbaenians, lizards, and snakes), Tuataras (lizard-like reptiles which currently present only one species distributed in New Zealand), and Turtles. Among amphibians, we have Caecilians (snake-like amphibians), frogs, and salamanders. Of this much, the Atlantic Forest harbors about 540 amphibians and over 200 reptile species.
In the field of herpetology, several types of studies can be performed, including those on:
• Venom: these studies provide one of the possible perspectives of snakes’ evolution (through proteomic research, like the project developed by Dr. Felipe Grazziotin, see below), besides the straightforward biological characterization of venom components and clinical aspects of envenomation. A popular and noble example of this research is that on the venom of the Jararaca (Bothrops jararaca), which enabled the discovery and production of a drug that aims to treat high blood pressure, the captopril.
• Ecology: research field that covers a wide range of possibilities, from the study of animal behavior to the analysis of intra and interspecific interactions. Aspects of the natural history of species (where and how species live) are also frequently described.
• Genetics: from tissue samples (e.g., blood, scales, muscle fragments), it is possible to argue about the evolutionary history of a species or to make ecological inferences about a population, for instance, about its genetic status (whether it is stable or weakened).
Since I decided to become a herpetologist, I have had the opportunity to photograph the astonishing Brazilian fauna. To trip over any species in its natural habitat, from the smallest to the largest ones, from the harmless to the most venomous is a fantastic experience. Among my encounters, I consider that with the Ribeira Boa (Corallus cropanii) one of the most remarkable, since this is an extremely rare and endangered snake. Its distribution is restricted to Vale-do-Ribeira (São Paulo State), and it has spent decades without being found (since the 1950s). In 2017, an individual was found in the Guapiruvu neighborhood, in Sete Barras municipality (São Paulo State). Once the species is poorly known, having the opportunity to observe its behavior amid its habitat is something matchless. When I followed the study of this species, we spent afternoons, nights, and early mornings with our eyes dipped into binoculars and cameras, ready for new records. After I have gone, researchers who were conducting the data collection recorded the snake with its body hanging downwards, holding on to a branch for the last third of its body, waiting for a prey to have the misfortune to pass through. Such a branch formed a “little corridor” which was possibly used by small mammals (e.g., arboreal rodents, possums). The Ribeira Boa must have captured chemical signals (e.g., urine) on that branch and then positioned itself for any opportunity of feeding. That is what we called a “sit-and-wait” foraging strategy and it is exactly what herpetologists yearn to see.
Another moment I will never forget was my first encounter with the Jararacussu (Bothrops jararacussu). A mixture of happiness, euphoria and a lot of adrenaline ran through my body, because despite working and knowing how to deal with such animals, a lot of caution is always necessary, especially in the field, where access to hospitals is usually tricky. We took about thirty minutes to capture the snake, which was approximately five feet long. It was striking (trying to bite) repeatedly and moving fast across the ground filled with roots and holes, which made it even more difficult to handle the snake. The fear of being bitten mixes with a feeling of anxiety about the possibility of losing an important specimen found at so much cost. Fortunately, we achieved that sample without accidents or injuries to the animal.
After meeting my current supervisor, Dr. Felipe Grazziotin, I started my story with these fantastic animals. Lucky for me, a big project was in the works. Funded by the São Paulo Research Foundation (FAPESP), the Scales of Biodiversity project accounts for several other researchers from the Butantan Institute, and a team of North American researchers. This study aims to investigate the evolution of snake venom glands in Brazil, Mexico, Costa Rica, and the United States, in order to reconstruct the evolutionary history of this enigmatic group and understand the relationship of venom attributes to their prey.
Recently, Felipe and I chose my Scientific Initiation project, which will analyze the evolution and systematics of Dipsas albifrons, popularly known as Sauvage Snail-eater, a slug-eating snake that has no venom and is commonly mistaken with the venomous snake Jararaca (Bothrops jararaca). Our objective is to infer the evolutionary processes that shaped the diversity of Dipsas albifrons through analyzes of genetic variability. Such studies aim to observe variations in alleles (variants of the same gene) that are responsible for granting the physiological and morphological characteristics of living beings.
When we started to collect data on the Sauvage Snail-eaters in the Zoological Collection of the Instituto Butantan, we discovered that there were not so many samples from the subject of our study. We needed to collect specimens in three different locations, Alcatrazes Island, Queimada Grande Island, and Ubatuba municipality. We started the fieldwork on the coast of São Paulo where I had the pleasure of visiting the dreaded Ilha das Cobras (Queimada Grande Island). In expeditions to the Atlantic Forest, we do not usually find more than five snakes in a single night, however on Queimada Grande in a few hours of searching we observed more than thirty Golden Lanceheads (Bothrops insularis). It is an endemic (restricted to a single location) snake on the Island which has a yellowish color and a venom that evolved in response to its specialized diet of birds (unlike its mainland relatives that when adults prey mostly rodents). In Alcatrazes we found nine Alcatrazes lancehead (Bothrops alcatraz), a relatively high number when compared to those of expeditions carried out in the continental Atlantic Forest. Both islands are located about thirty-five kilometers off the coast of Itanhém municipality (Ilha da Queimada Grande) and São Sebastião municipality (Island of Alcatrazes).
Lacking only samples from the continent, we assembled a team made up of researchers from the Butantan Institute and three herpetologists, Rafael Menegucci, Rafael Mitsuo, and Lucas Ramiro, and started our expedition in Ubatuba (São Paulo state). The very touristic city has an extensive untouched area of Atlantic Forest. Its territory encompasses 102 beaches and 16 islands, which offer various leisure activities (surfing, diving, bird watching, fishing, among others) and attracts tourists from all over the world.
There were lots of eyes looking for Sauvage Snail-eater that day, however, that didn’t free us from the obstacles of the weather. It was a cold night, and it rained a lot (those rains that flood wellies). Even so, for that region, we found a relatively large number of individuals for some species. Among the snakes, five Brown Sipo (Chironius fuscus) and one Jararacu çu (Bothrops jararacussu), both species are common in Ubatuba. Among amphibians, the Split-Backed Frog (Fritziana cf. fissilis.), one of the few frogs that carry their young on their back during their developmental period (marsupial frogs), the Spotted Leaf Frog (Phasmahyla guttata), and an Ocellated Treefrog (Itapotihyla langsdorffii). Unfortunately, we couldn’t find the snake we were looking for.
Eight months later, we scheduled a new expedition in search of Sauvage Snail-eater. After a light rain, the swamps became noisy, and several species of amphibians called at the foothills of the Serra do Mar mountains. After a few hours of unsuccessfully searching, I stopped to rest. With an unassuming movement, I poked a tuft of grass to discover a young Jararacu çu (Bothrops jararacussu). It didn’t take long and a few meters later I found another snake of the same genus, a Pit viper (Bothrops jararaca) curled up in a tree about 60 cm from the ground. I didn’t think I could be happier during this trip, but during our stay in Ubatuba, a local resident found a snake and called us to pick it up. It was a Serra Snake (Tropidodryas serra), an elusive and hard-to-find Atlantic Forest snake.
Finding these animals in nature is always an unforgettable experience, full of adrenaline and happiness. Unfortunately, we still haven’t found Sauvage Snail-eater that was the focus of my expeditions, but soon we will continue our journey in search of this snake in the immense forest of Serra do Mar.
