Head to head
Saddleback Caterpillar vs Hag Moth
The saddleback caterpillar and hag moth caterpillar are both venomous slug caterpillars capable of a genuinely painful sting, but they take completely opposite approaches to warning, or not warning, anything that gets too close.
| Saddleback Caterpillar | Hag Moth | |
|---|---|---|
| Scientific name | Acharia stimulea | Phobetron pithecium |
| Warning strategy | Bold, visible warning colouration | Camouflage disguising the danger |
| Caterpillar appearance | Green saddle marking on a smooth body | Resembles a tuft of dead leaves or fur |
| Venom delivery | Spines across the body | A subset of hair-like projections |
| Alternate common name | None widely used | Monkey slug |
| Habitat | Forest and garden habitat | Forest habitat |
| Conservation status | Least Concern | Least Concern |
| Diet | Herbivore | Herbivore |
Saddleback Caterpillar vs Hag Moth: common questions
Which is more dangerous to touch, the saddleback caterpillar or the hag moth caterpillar?
Both deliver a genuinely painful sting, but they warn about it very differently: the saddleback caterpillar displays a bold green saddle marking that clearly signals danger, while the hag moth caterpillar disguises its venomous hairs among many harmless-looking projections that make it resemble dead leaves, arguably making it the more hazardous of the two simply because it gives so little visual warning.
Why does the hag moth caterpillar look nothing like a typical caterpillar?
This species is covered in curling, hair-like projections of varying lengths that closely resemble a tuft of dead leaves, fur, or debris, an unusual camouflage strategy quite different from the saddleback caterpillar's approach of displaying a bold, clearly visible warning pattern rather than trying to hide at all.
Do the saddleback caterpillar and hag moth caterpillar turn into similarly dramatic adult moths?
No, both species transform into comparatively plain, unremarkable brownish adult moths, a considerable contrast for the hag moth caterpillar especially, whose bizarre debris-like larval appearance gives no hint of the far more ordinary-looking moth it will eventually become.