Mydas clavatus
In 3 days ~10% in a week ~20%
Mydas clavatus, the clubbed mydas fly, is a species of Mydas fly that is native to temperate, eastern North America. It is named for its clubbed antennae, which is however a general feature of the Mydas flies. An orange to red mark on the abdomen is distinctive. It is a Batesian mimic of certain spider wasps, and is consequently quite bold in its movements. Adults fly in mid-summer.
They are large, black and somewhat glabrate flies that measure some 25 to 30 mm in length, with a wingspan that may exceed 50 mm. A prominent orange to red mark is evident on the ventral side of the second abdominal segment. Their visual mimicry is apparently complemented by curling and jabbing of the abdomen in a mock stinging routine.
The eggs are deposited singly in soil or rotting wood. The larvae, as with M. brunneus and M. tibialis, are predatory on the larvae of deadwood-feeding scarab beetles (Osmoderma species.) and can be found in standing and downed trees with extensive heart rot. The adults seem to be pollen and nectar feeders only, and have been observed at Asclepias, Saponana, Spiraea, Monarda, Pycnanthemum, Teucrium and Verbena flowers. When not nectaring,... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Point Pelee National Park | 🇨🇦 Canada | |
| 2 | Shenandoah National Park | 🇺🇸 United States | |
| 3 | Merritt Island National Wildlife Refuge | 🇺🇸 United States | |
| 4 | Everglades National Park | 🇺🇸 United States | |
| 5 | Great Smoky Mountains National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Detroit | 🇺🇸 United States | |
| 2 | Houston | 🇺🇸 United States | |
| 3 | Chicago | 🇺🇸 United States | |
| 4 | Baltimore | 🇺🇸 United States | |
| 5 | Austin | 🇺🇸 United States | |
| 6 | Philadelphia | 🇺🇸 United States | |
| 7 | Boston | 🇺🇸 United States | |
| 8 | Dallas | 🇺🇸 United States | |
| 9 | Washington | 🇺🇸 United States | |
| 10 | San Antonio | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Clubbed Mydas Fly sighting in Great Smoky Mountains National Park on a given day, based on 5 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 628th most-seen of the 822 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
June and July
In those months about 10% of wildlife watchers report a Clubbed Mydas Fly in Great Smoky Mountains National Park on a given day, against under 5% in August to May, the lowest months.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most Clubbed Mydas Fly sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.
5th of 5
Of the 5 parks where we can rate Clubbed Mydas Fly sightings, Great Smoky Mountains National Park ranks 5th at under 5%. The best odds are in Point Pelee National Park (Canada, about 10%), Shenandoah National Park (United States, about 10%) and Merritt Island National Wildlife Refuge (United States, under 5%).
Same order: Diptera
The closest relatives of the Clubbed Mydas Fly that you can see in Great Smoky Mountains National Park (order Diptera, Flies) are Eastern Calligrapher (about 20%), Margined Calligrapher (about 10%) and Ocellate Gall Midge (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Clubbed Mydas Fly is recorded against all the insects logged in Great Smoky Mountains National Park (5 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.
