The saying goes that good things come in small packages, but so too do tiny, deadly amphibians. New research published in the journal PLOS ONE recovered one such zoological parcel in the south Mantiqueira mountain range of São Paulo, Brazil. The magnificently orange death-nugget hails from the genus Brachycephalus, a group that has experienced some taxonomical difficulties owing to the fact that its members are morphologically and genetically quite hard to tell apart.
The newest member had historically been lumped in with the pumpkin toadlet species Brachycephalus ephippium that’s found in São Paulo. However, when a particularly orange frog with a head rounder than it is long and an unfamiliar song came onto the scene, local biologists grew suspicious.
Pumpkin toadlets are named for their impressive orange coloration, though their resemblance to the large squash ends here, being themselves just the size of a thumbnail. The poisonous frogs all look quite similar and exhibit few genetic variations, making it all the more understandable that unique species can go unnoticed to science for quite some time.
Ascertaining that there was indeed a distinct species in the mix required an integrated approach owing to the pumpkin toadlets’ inconveniently enduring pumpkin toadletness. To tell them apart, the researchers employed genetic and anatomical analyses to document and compare living and museum specimens. The turbo-orange toadlet’s unique song was also crucial in telling it apart from Brachycephalus ephippium. Finally, the new species was named Brachycephalus rotenbergae.
Its existence was first hinted at by Thais Helena Condez, a herpetologist from the Instituto Nacional da Mata Atlântica, whose paper used genetic sampling to highlight the possibility of a new, unidentified pumpkin toadlet species. “The new study follows our first evidence,” said Condez to The Smithsonian, “and shows an integrative approach considering distinct information based on genetics, morphology and bioacoustics.”
With a rather squat build and adorably grumpy face, B rotenbergae is thought to occupy the forest floor as a diurnal animal that marches about during the day. As well as having brilliantly orange skin, it can fluoresce green under UV light (not unheard of in pumpkin toadlets) thanks to unusual bony plates on its skull and back, though exactly what purpose (if any) this feature serves is up for debate. Being so small, pumpkin toadlets might look like easy pickings to passing predators, but their bright coloration is a warning that ingesting their neurotoxin-coated bodies is a bad idea.
You win this round, forbidden pumpkin popper.