A team of biologists (生物学家) recently studied wildlife in the forests of northern Ecuador. While doing so, they made a surprising discovery: a Mindo harlequin toad (明多斑足蟾). The creature hadn't been seen alive in 30 years. The scientists couldn't believe their eyes. "It took our brains a while to believe it was a Mindo harlequin toad," says Melissa Costales, a conservation biologist from University of New Brunswick.
The Mindo harlequin is the latest harlequin toad species "to come back from the dead," says Costales. Since 2003, eight others have been found, three of them in Ecuador.
Until recently, 13 of the 25 species of harlequin toads in Ecuador had gone unseen since the 1980s or early 1990s. Scientists thought most of them had been killed by a disease called chytrid (壶菌). This illness is especially harmful to the harlequin toad.
Costales says the Mindo harlequin toad may have developed a resistance (抵抗力) to the disease. That would explain the toad's reappearance. And it could spell good news for other harlequins. Since discovering the first one, Costales's team has found five more. They were all tested for chytrid. None had the disease. But that doesn't mean the survival of the species is guaranteed (保证), Costales says. The harlequin toad is still endangered.
Costales is developing a conservation plan with a zoology museum in Ecuador. She wants to make sure the Mindo harlequin toad doesn't fall back into extinction. "Each rediscovery gives us a second chance to develop better conservation plans," she says. "Not every day do we have the chance to rediscover a species that we believed to be extinct."
