Chelymorpha cassidea
In 3 days ~20% in a week ~50%
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 |
With luck
About 10% of wildlife watchers report an Argus Tortoise Beetle sighting in Big Cypress National Preserve on a given day, based on 8 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 154th most-seen of the 262 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 50%, if each day is a fresh chance.
August
In that month about 20% of wildlife watchers report an Argus Tortoise Beetle in Big Cypress National Preserve on a given day, against under 5% in March, May, July, September and December–January, the lowest months. That is one of Big Cypress National Preserve's wettest months, with about 210 mm of rain against 40 mm in March.
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 2 parks where we can rate Argus Tortoise Beetle sightings, Big Cypress National Preserve ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Badlands National Park (United States, about 10%).
Same family: Chrysomelidae
The closest relatives of the Argus Tortoise Beetle that you can see in Big Cypress National Preserve (family Chrysomelidae, Leaf Beetles) are Aethiopocassis scripta (about 20%), Palmetto Tortoise Beetle (about 10%) and Neolochmaea dilatipennis (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 Big Cypress National Preserve (8 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.
