Cecropia moth vs Promethea moth
These two are easy to mix up. Here's how to tell a Cecropia moth from a Promethea moth, and whether either one bites or stings.
Cecropia moth
Hyalophora cecropia
Promethea moth
Callosamia promethea
≠The key differences
Promethea is smaller and darker with less contrasting white bands; wing shape and size are noticeably different.
⚖︎Side by side
| Cecropia moth | Promethea moth | |
|---|---|---|
| To humans | Non-toxic | Non-toxic |
| Size | Wingspan 120-160 mm (12-16 cm) | 7.5-9.5 cm wingspan |
| Colours | Reddish-brown, Cream, Black, Orange, Green (larva) | Reddish brown, Dark brown, Cream/white, Black |
| Family | Saturniidae | Saturniidae |
| Habitat | Deciduous woods, woodland edges, parks, suburbs and gardens where host trees grow | Deciduous forests, forest edges, riparian corridors and suburban areas with host trees |
| Range | Widespread across much of North America: from southern Canada through much of the United States (ranges vary by local populations) | Eastern North America: from southern Canada through the eastern United States |
| Active | Adults on wing late spring through summer (timing varies by latitude); mostly night-active (nocturnal) | Late spring to midsummer; one generation in the north, one or two generations farther south; adults fly at dusk and night, males often active during the day |
| Pest? | No | No |
🔍How to spot a Cecropia moth
- Very large wingspan (12-16 cm) with rounded wings and bold bands of white, black and reddish-brown.
- Crescent-shaped pale spots and small crescent eyespots on each wing.
- Males with large feathered antennae; females with somewhat less plumose antennae.
- Large green caterpillars with rows of colored tubercles; pupae inside a brown, papery silken cocoon.
🔍How to spot a Promethea moth
- Sexual dimorphism: females are reddish-pink with broad pale bands; males are darker brown and smaller.
- Wingspan 7.5-9.5 cm with rounded hindwings typical of silk moths.
- Small translucent or pale cell spot on each forewing.
- Found on or near host trees (spicebush, sassafras, wild cherry, tulip tree, sweetgum).
?Frequently asked questions
What is the difference between a Cecropia moth and a Promethea moth?
Promethea is smaller and darker with less contrasting white bands; wing shape and size are noticeably different.
Is a Cecropia moth or a Promethea moth more dangerous?
Cecropia moth: Non-toxic. Promethea moth: Non-toxic. Adults and caterpillars are not poisonous and do not sting. Adults do not bite or sting and are harmless.
Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.