Tetraopes tetrophthalmus
In 3 days ~50% in a week ~80%
Tetraopes tetrophthalmus, the red milkweed beetle, is a beetle in the family Cerambycidae. The binomial genus and species names are both derived from the Ancient Greek for "four eyes." As in many longhorn beetles, the antennae are situated very near the eye–in the red milkweed beetle, this adaptation has been carried to an extreme: the antennal base actually bisects the eye.
The milkweed beetle, an herbivore, is given this name because it is host-specific to common milkweed (Asclepias syriaca). It has been reported on horsetail milkweed (Asclepias verticillata) in a disturbed site in Illinois.
Adults feed on the foliage and flowers of the plant, and the larvae feed on the roots. Therefore, much like the monarch butterfly, it is thought that the beetles derive some protection from predators by incorporating toxins from the plant into their bodies, thereby becoming distasteful. The red and black coloring are aposematic, advertising the beetles' inedibility.
These beetles feed by opening veins in the milkweed plant, decreasing the beetles' exposure to latex-like sap. When startled, the beetles make a shrill... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Shenandoah National Park | 🇺🇸 United States | |
| 2 | Great Smoky Mountains National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 2 | Detroit | 🇺🇸 United States | |
| 3 | Chicago | 🇺🇸 United States | |
| 4 | Boston | 🇺🇸 United States | |
| 5 | Toronto | 🇨🇦 Canada | |
| 6 | Montreal | 🇨🇦 Canada | |
| 7 | Philadelphia | 🇺🇸 United States | |
| 8 | Baltimore | 🇺🇸 United States | |
| 9 | New York City | 🇺🇸 United States | |
| 10 | Washington | 🇺🇸 United States |
Possible
About 20% of wildlife watchers report a Red Milkweed Beetle sighting in Shenandoah National Park on a given day, based on 81 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 31st most-seen of the 723 insects we can rate there. Over three days the chance rises to about 50%, and over a week to about 80%, if each day is a fresh chance.
June and July
In those months about 30% of wildlife watchers report a Red Milkweed Beetle in Shenandoah National Park on a given day, against under 5% in September to April, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Red Milkweed Beetle sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 2 parks where we can rate Red Milkweed Beetle sightings, Shenandoah National Park has the highest daily chance: about 20%. Next come Great Smoky Mountains National Park (United States, about 10%).
Same family: Cerambycidae
The closest relatives of the Red Milkweed Beetle that you can see in Shenandoah National Park (family Cerambycidae, Longhorn Beetles) are Locust Borer (about 20%), Strangalepta Flower Longhorn Beetle (about 10%) and Broad-Necked Root Borer (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Red Milkweed Beetle is recorded against all the insects logged in Shenandoah National Park (81 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.
