Scientist spots rare dragonfly near water
A scientist with the New York City Department Environmental Protection recently spotted and photographed a Southern pygmy clubtail, an extremely rare species of dragonfly, in a tributary of the Rondout Reservoir, according to the department.
The pygmy clubtail can only survive and reproduce in clean, clear waters, making it a reliable indicator of water quality, the Department Environmental Protection (DEP) said in a press release.
“Its larvae are intolerant of excessive sedimentation and therefore serve as excellent indicators of water quality,” the DEP said. “Because the species needs cold water to survive and thrive, this particular dragonfly and its larvae are also helpful in pinpointing waters that are suitable for brook trout.”
The press release said Frank Beres, a department scientist, discovered the dragonfly while taking a short hike to a water-quality sampling site in the forest surrounding the Rondout Reservoir, which straddles the border of Ulster and Sullivan counties. The dragonfly landed on his finger, allowing him to take several photos of it before it flew off, the department said.
“One of the most exciting moments for an ecologist or naturalist in the field is the sighting of a rare species,” Beres said in a prepared statement.
Beres has photographed and documented thousands of macroinvertebrates, insects, birds and other animals, the DEP said.
Adult pygmy clubtails reach a size of just 4 centimeters and are secretive and rarely viewed, so scientists know little about their life, habits and population dynamics, the department press release said.
The department said the species is considered critically imperiled in New York ans that many experts fear localized extinction in the few places where it is known to exist.
The Southern pygmy clubtail originates from an ancient genus, Lanthus, and branched into three species more than 175 million years ago, according to te DEP.
The Rondout Reservoir, which is partly in the Ulster County town of Wawarsing and partly in the Sullivan County town of Neversink, is part of New York City’s vast upstate water supply system. The system comprises 19 reservoirs, three controlled lakes and numerous tunnels and aqueducts.