Copestylum mexicanum
In 3 days ~20% in a week ~40%
Copestylum mexicanum, the Mexican cactus fly, is a species of syrphid fly in the family Syrphidae. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Saguaro National Park | 🇺🇸 United States | |
| 2 | Big Bend National Park | 🇺🇸 United States | |
| 3 | Everglades National Park | 🇺🇸 United States | |
| 4 | Cumbres de Monterrey National Park | 🇲🇽 Mexico |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | San Diego | 🇺🇸 United States | |
| 2 | Los Angeles | 🇺🇸 United States | |
| 3 | Sacramento | 🇺🇸 United States | |
| 4 | Mexico City | 🇲🇽 México | |
| 5 | Monterrey | 🇲🇽 México | |
| 6 | Mesa | 🇺🇸 United States | |
| 7 | San Antonio | 🇺🇸 United States | |
| 8 | Phoenix | 🇺🇸 United States | |
| 9 | Austin | 🇺🇸 United States | |
| 10 | San Francisco | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Mexican Cactus Fly sighting in Saguaro National Park on a given day, based on 17 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 134th most-seen of the 354 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
March–June and October–November
In those months about 10% of wildlife watchers report a Mexican Cactus Fly in Saguaro National Park on a given day, against under 5% in July–September and December–February, the lowest months. Those are among Saguaro National Park's driest months, with about 15 mm of rain a month against 55 mm in July.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Mexican Cactus 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 4 parks where we can rate Mexican Cactus Fly sightings, Saguaro National Park has the highest daily chance: about 10%. Next come Big Bend National Park (United States, about 10%) and Everglades National Park (United States, about 10%).
Same genus: Copestylum
The closest relatives of the Mexican Cactus Fly that you can see in Saguaro National Park (genus Copestylum, Bromeliad Flies) are Copestylum marginatum (about 10%), Isabelle's Bromeliad Fly (about 10%) and Copestylum apiciferum (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Mexican Cactus Fly is recorded against all the insects logged in Saguaro National Park (17 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.
