Eristalis transversa
In 3 days ~40% in a week ~70%
Eristalis transversa, the transverse banded drone fly, is a common species of hoverfly first officially described by Wiedemann in 1830. Hoverflies get their names from the ability to remain nearly motionless while in flight. The adults are also known as flower flies for they are commonly found around and on flowers, from which they get both energy-giving nectar and protein-rich pollen. The larvae are rat-tailed type but larvae of this specific species has not been reported.
external map Species reported from North America east of the Mississippi River and into Southeastern Canada. For terms see Morphology of Diptera. external images Size 7–12 mm (0.28–0.47 in) Head The eyes are pilose on upper half and broadly contiguous in the male. The front is black, shining in the middle, black pile on the sides. The female also with black pile, narrowed above but on the lower two-thirds reddish pollinose. The antennae are reddish yellow. The basal portion of arista sparsely plumose. The sides of the face covered with dense whitish pollen and whitish pile, the median stripe (tubercle) and cheeks are shining black.
Thorax The notum is opaque black, with three... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Acadia National Park | 🇺🇸 United States | |
| 2 | Point Pelee National Park | 🇨🇦 Canada | |
| 3 | Shenandoah National Park | 🇺🇸 United States | |
| 4 | Great Smoky Mountains National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Boston | 🇺🇸 United States | |
| 2 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 3 | Toronto | 🇨🇦 Canada | |
| 4 | New York City | 🇺🇸 United States | |
| 5 | Washington | 🇺🇸 United States | |
| 6 | Detroit | 🇺🇸 United States | |
| 7 | Philadelphia | 🇺🇸 United States | |
| 8 | Chicago | 🇺🇸 United States | |
| 9 | Montreal | 🇨🇦 Canada | |
| 10 | Baltimore | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Transverse-Banded Flower Fly sighting in Boston on a given day, based on 392 verified sightings from GBIF citizen-science data. It is the 40th most-seen of the 1200 insects we can rate there. Over three days the chance rises to about 40%, and over a week to about 70%, if each day is a fresh chance.
August
In that month about 30% of wildlife watchers report a Transverse-Banded Flower Fly in Boston on a given day, against under 5% in December to April, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Transverse-Banded Flower Fly sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 11 cities where we can rate Transverse-Banded Flower Fly sightings, Boston has the highest daily chance: about 10%. Next come Minneapolis [Saint Paul] (United States, about 10%) and Toronto (Canada, about 10%).
Same genus: Eristalis
The closest relatives of the Transverse-Banded Flower Fly that you can see in Boston (genus Eristalis, Drone Flies) are Common Drone Fly (about 10%), Black-Shouldered Drone Fly (about 10%) and Eurasian Drone Fly (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Transverse-Banded Flower Fly is recorded against all the insects logged in Boston (392 verified sightings), 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.
