Historic numbers of animals across the globe have become endangered or pushed to extinction. But some of these species sit in limbo — not definitively extinct yet missing from the scientific record. Rediscovering a "lost" species is not easy. It can require trips to remote areas and canvassing a large area in search of only a handful of animals. But new technology and stronger partnerships with local communities have helped these hidden, "uncharismatic" creatures come to light.

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The De Winton's golden mole was last spotted in 1936. But with the help of a mole-sniffing dog and new environmental DNA analysis, researchers are taking it off the most wanted lost species list.