Tachopteryx thoreyi
In 3 days ~10% in a week ~30%
Tachopteryx thoreyi, commonly known as the gray petaltail and Thorey's grayback, is a species of dragonfly. It is native to the East Coast of the United States from New York to Florida, and west to Texas. This species is the only member of the monotypic genus Tachopteryx.
The gray petaltail lives in highlands, woodlands, and deciduous forests with permanent seeps, often indicated by the presence of skunk cabbage and ferns. The gray petaltail is primarily gray and black in color; the thorax is usually entirely gray, while the abdomen is gray and black. The adult is 7.1 to 8.0 centimeters in length. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 2 | Shenandoah National Park | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Gray Petaltail sighting in Shenandoah National Park on a given day, based on 8 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 447th most-seen of the 723 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
May to July
In those months about 10% of wildlife watchers report a Gray Petaltail in Shenandoah National Park on a given day, against under 5% in August to April, the lowest months.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most Gray Petaltail sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 2 parks where we can rate Gray Petaltail sightings, Shenandoah National Park ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Great Smoky Mountains National Park (United States, about 10%).
Same order: Odonata
The closest relatives of the Gray Petaltail that you can see in Shenandoah National Park (order Odonata, Dragonflies and Damselflies) are Ebony Jewelwing (about 10%), Common Whitetail (about 10%) and Widow Skimmer (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Gray Petaltail is recorded against all the insects logged in Shenandoah National Park (8 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
