An extremely rare dragonfly, which many believed was extinct, was spotted in the Hudson Valley.

On Monday, the New York City Department of Environmental Protection (DEP) announced that one of its field ecologists discovered an extremely rare species of dragonfly living along a small tributary that feeds Rondout Reservoir in the Catskills. The Rondout Reservoir is split between Ulster and Sullivan counties.

The dragonfly, known as the Southern pygmy clubtail, can only survive and reproduce in extremely clear, clean waters, making them an exceptional indicator of water quality, officials say.

This particular species of dragonfly is considered critically imperiled in New York, and it is rare enough that many experts fear localized extinction in the few places where it is known to exist.

DEP scientist Frank Beres discovered the dragonfly during a short hike to a water-quality sampling site in the forest surrounding Rondout Reservoir. After Beres spotted it, the Southern pygmy clubtail hopped on his finger and allowed him to take several excellent photos before flying off.

“One of the most exciting moments for an ecologist or naturalist in the field is the sighting of a rare species,” Beres said. “This chance encounter with a rare, unique, secretive and delicate organism that requires a specific, pristine habitat emphasizes the ecological intricacies of the Catskills and the importance of all work performed to assess and protect lands and waters in the watershed.”

According to the DEP, the Southern pygmy clubtail originates from an ancient genus, Lanthus, that branched into three species more than 175 million years ago. Two of those three species live in New York. Its dwindling population in New York and the Northeast have been documented since 2000, and a five-year survey failed to find the dragonfly at half the New York sites where it was known to historically exist. As a result, the Southern pygmy clubtail was upgraded to “critically imperiled” by the New York Natural Heritage Program in 2012. That ranking describes species that are especially vulnerable to extirpation, or localized extinction, in New York due to their rarity, restricted range and habitat, or steep population decline.

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