A scientist peeked under a rock and found an unusually colored mutant of a venomous funnel-web spider. Until Mark Wong recently flipped over a rock in Tallaganda State Forest in New South Wales, Australia, it had been just another day of looking at spiders. Then, the ecologist spotted the burrow of Atrax sutherlandi, a funnel-web spider. “I began poking at it with a stick, and I was amazed at what came rushing out at me. The first thing that caught my eye was the red fang,” says Wong. (Also see “New ‘Blue Face’ Peacock Spider Is Fancy Dancer.”) Normally, A. sutherlandi has a glossy black back and fang, as well as a deep-brown or plum underbelly. The spider that sprung from the burrow, however, had a blood-red belly and fang. Wong knew immediately that he had made an once-in-a-lifetime discovery. “I had never seen a funnel-web spider with those colors before”—and it turns out no one else had, either, says Wong, a National Geographic Young Explorer and Ph.D. student at the Australian National University in Canberra. It’s very common for individual animals, even spiders, to have different colors, says Amber Beavis, a spider expert and senior researcher at the Regional Australia Institute, an independent think tank in Canberra. “There’s more variation than you might think,” Beavis says. But the red-fanged spider struck her as a particularly unusual find. “I spent five years in this area looking for spiders, and I didn’t see anything like it.”