It may look cute and glow a cool fluorescent orange, but a newly identified species of frog in Brazil is highly toxic, scientists reveal.
The frog, called Brachycephalus Rotenbergae, is just under an inch long but has enough venom that is transmitted from the glands in its skin to make a person sick.
It also has bony plates on its skull and back that glow green through the skin under ultraviolet (UV) light – but researchers aren’t sure why.
B. Rotenbergae was discovered south of the Mantiqueira Mountains in the Brazilian state of São Paulo in the forest along the Brazilian Atlantic coast.
The newly identified species, Brachycephalus Rotenbergae, is shown – note the defensive mouth gaping behavior
It is a type of pumpkin toad (Brachycephalus ephippium), a group of related species of fluorescent, brightly colored frogs whose shade resembles the pumpkin that gives it its name.
The newly identified species is poisonous and potentially fatal to small mammals and birds – but its threat to humans is minimal, according to study author Ivan Nunes of the Universidade Estadual Paulista.
People can touch them with their bare hands, but shouldn’t touch their eyes or mouth afterwards to avoid the risk of disease.
The species B. Rotenbergae was discovered south of the Mantiqueira Mountains in the Brazilian state of São Paulo in the forest along the Brazilian Atlantic coast
“The species is very poisonous, but only for the animals that try to eat it,” Nunes told MailOnline.
‘Predators (birds, mammals, larger frogs) can die if they eat the brachycephalus.
“We can manipulate them with our bare hands, without gloves, no problem with that – we just can’t touch our eyes or mouth afterwards.
“When we do that, we can feel a little bad [but] Washing hands can solve the problem. ‘
Other frogs of the same genus carry an extremely dangerous poison called tetrodotoxins in their skin, and probably B. Rotenbergae as well.
(A) shows the back view, (B) the front view, (C) the side view of the head, (D) the front view of the hand, (E) the front view of the feet
Tetrodotoxins disrupt the signals transmitted between nerves and muscles and lead to muscle paralysis.
They are also found in the deadly fugu puffer fish, known for being specially prepared for consumption in Japanese restaurants so that it is no longer fatal.
B. Rotenbergae spends most of its time in the forest floor and was photographed by the researchers crouching between branches.
It is possible that the ultra-bright appearance served as a warning to predators that they are carrying venom, but it could also have been developed so that potential mates can find each other in low light.
Or, their appearance could simply be used as an effective camouflage, suggest the study authors.
“There are large amounts of tiny yellow and orange leaves, mushrooms and seeds on the ground, especially during the active season,” they point out.
(A) A man wraps a woman with his front legs around her waist; (B) A couple hiding under a Juçara palm; (C) mouth gaping defense behavior; (D) A specimen near a yellow / orange mushroom (note the similarity of color and size); (E) an adolescent sample; (F) Two juvenile specimens, but the smaller one is darker
The researchers say that B. Rotenbergae may differ from other pumpkin toads in its morphological features (particularly the structure of the bones and head shape), voice call, and DNA gene sequences.
However, you’re still not sure why it gives off such an impressive fluorescent glow under UV light.
“There’s an idea that fluorescence acts as a signal for potential mates to signal rival men or some other biological role,” Nunes told Smithsonian.
The species has bony plates on the skull and back that glow green through the skin under UV light. Shown here at a wavelength of 395 nm (UV, below the visible range)
The researchers had traveled south of the Mantiqueira Mountains several times to collect pumpkin toads.
The team collected 276 pumpkin toad samples (aided in part by the use of fluorescent light), which they brought back to their laboratory for analysis, including DNA testing.
Analysis found that some of the frogs had new features, including faded dark spots on the skull and a rounded snout, that differed from the other species they collected.
This heralded the discovery of a new species, which they named B. Rotenbergae after a Brazilian conservationist named Elise Laura K. Rotenberg.
Rotenberg is the founder of the Brazilian NGO Projeto Danis, a project to preserve the forest in which the toads live.
The type is explained in more detail in PLOS One.
WHY SHOULD YOU NOT LICK A FROG?
There are a number of toxins in frog and toad skin that are believed to protect them from predators.
In the genus Atelopus, most of these chemicals are tetrodototoxins – a powerful neurotoxin.
According to the CDC, tetrodototoxins disrupt the signals transmitted between nerves and muscles and lead to muscle paralysis.
Since this also applies to the respiratory tract, poisoning with this toxin can lead to respiratory failure and ultimately death.
Researchers have also found zetekitoxins in A. zeteki and chiriquitoxins in A. limosus.
Some forms of zetekitoxin are known as powerful cardiotoxins that have drastic effects on the heart, and scientists have found that chiriquitoxins are a natural analog of tetrodotoxin.
While these toxins could be used for treatments, they can also be deadly.
“Remarkably, toxins from a single frog skin can kill 130-1000 mice,” said Candelario Rodriguez, a researcher at INDICASAT in Panama.
“The mechanism of action is to reduce the heart rhythm and turn these interesting candidates into therapeutic compounds.”