Chelymorpha cassidea
In 3 days ~10% in a week ~20%
Chelymorpha cassidea, known generally as the Argus tortoise beetle or milkweed tortoise beetle, is a species of leaf beetle in the family Chrysomelidae. It is found in the Caribbean and North America. The beetle is 9 to 12 mm (0.35 to 0.47 in) long and is yellow to bright red with black spots. It is one of the largest leaf beetles native to North America. The name Argus comes from the mythical Greek giant Argus Panoptes, who was sometimes depicted with 100 eyes, because the beetle is able to stretch out its red head beyond its pronotum, as if it were a single red eye. The species resembles a small turtle and is similar to a ladybug.
The Argus tortoise beetle lays eggs on leaves, in clusters of 15 to 30. The eggs hatch within 10 days. Its larvae are yellowish-green or orange-yellow. The larvae feed on leaves until they are fully grown, then they drop to the soil to pupate, overwintering as pupae before emerging as adults in the middle of summer. It takes them almost three weeks to become pupae.
The beetle can be found throughout North America in meadows and roadsides. It can also be found in the Caribbean. It feeds... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Badlands National Park | 🇺🇸 United States | |
| 2 | Big Cypress National Preserve | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Houston | 🇺🇸 United States | |
| 2 | Denver | 🇺🇸 United States | |
| 3 | Chicago | 🇺🇸 United States | |
| 4 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 5 | Washington | 🇺🇸 United States | |
| 6 | New York City | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report an Argus Tortoise Beetle sighting in Chicago on a given day, based on 13 verified sightings from GBIF citizen-science data. It is the 538th most-seen of the 978 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.
Any time of year
In every month with enough records, under 5% of wildlife watchers report an Argus Tortoise Beetle in Chicago on a given day, so our monthly data shows no clear season.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Argus Tortoise Beetle sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 6 cities where we can rate Argus Tortoise Beetle sightings, Chicago ranks 3rd at under 5%, level with the leaders once rounded. The best odds are in Houston (United States, under 5%) and Denver (United States, under 5%).
Same family: Chrysomelidae
The closest relatives of the Argus Tortoise Beetle that you can see in Chicago (family Chrysomelidae, Leaf Beetles) are Spotted Cucumber Beetle (about 10%), Swamp Milkweed Leaf Beetle (about 10%) and Dogbane Leaf Beetle (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Argus Tortoise Beetle is recorded against all the insects logged in Chicago (13 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.
