For centuries, a highly venomous snake has managed to slither under the scientific radar in the Australian bush.
Now, scientists have finally identified the new species of death adder, Acanthophis cryptamydros, which lives in the northwestern corner of the continent.
“It was a huge surprise. We weren’t even looking for a new species. I redid my work to make sure I hadn’t made a mistake,” says study leader Simon Maddock, a Ph.D. student in a joint program at University College London and the Natural History Museum, London.
The newfound species is 20 inches (51 centimeters) long and, like many other death adders, has a light reddish-brown color.
Maddock made his discovery not by trekking through the Australian outback but by studying the DNA of various death adders, a group of snakes native to Australia, New Guinea, and Indonesia that are among the world's most venomous. (Read "What's the Most Toxic Snake?")
Hiding in Plain Sight
Many of the approximately eight species of death adder—there’s some controversy about exactly how many species exist—are hard to tell apart, since individuals of the same species can sport remarkably different colors and patterns.
The newfound death adder "looks a lot like the northern death adder, A. rugosus, and that’s probably why no one discovered it until now," Maddock notes.
Using various death adder DNA from museums and some gathered specifically for his work, Maddock and colleagues sequenced certain genes into figure out how and when the reptiles evolved.
"When we looked at our DNA data, we found there was one group of snakes that were really, really different,” said Maddock, whose study was published recently in the journal Zootaxa. (See National Geographic's snake pictures.)
To show definitively that he had discovered a new species, Maddock requested additional specimens from museums around the world, and his colleagues went into the field to capture more snakes. In total, he analyzed 112 specimens, including 32 of the new death adder species.
“It’s a very thorough and important study,” says Dan Rabosky, an evolutionary biologist and curator of herpetology at the University of Michigan.
“Most of us think of Australia as a First World country that’s been thoroughly explored, and this shows how little we know.”
The western half of Australia, especially the Kimberley region and the Northern Territory, hosts a tremendous range of species, including several death adders.
“It’s a very ancient, stable environment, and there are a lot of species that are just hanging on out there,” says study leader Maddock.
Unlike some snakes, which hunt by chasing down their prey, a death adder waits for a victim to cross its path, wiggling its small, worm-like tail as a lure.
When the muscular predator spots a small rodent, lizard, or snake (their favorite food), it strikes, darting out and sinking its fangs and deadly venom into its next meal. (Read about National Geographic venom expert Zoltan Takacs.)
Despite their ominous name, death adders don't seek out people, and will only bite if they feel a threat is very close. Some believe that the term "death adder" is likely a confusion of "deaf adder," since these snakes cannot hear sounds.
You could say it puts a new spin on silent but deadly.
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