Spotting the Difference Between a Butterfly and a Moth

Black and orange Thai butterfly.jpgPhoto: Michael

As the summer season comes to an end, migration will literally be in the air for many winged creatures, from birds to bats. Along for the seasonal trek will be some species of butterflies and moths. While you can probably tell a bird apart from a bat quite easily if they are not too far away, you might have a harder time telling a butterfly apart from a moth even up close. Next time you see one of them, check for the following characteristics.

MothPhoto: Shyamal


Except for one group of tropical butterflies, all butterflies have simple antennae that end in a swelling that looks like a knob or club. The clubs are very pronounced in certain species. Moth antennae do not have this structure, although their antennae range in shape and texture.

Swallowtail butterflyPhoto: Jillski

Body – Thorax

Butterflies have bright colors and slender bodies that are not fuzzy. Moths have hairy bodies (pubescent) that are not usually colorful. They have cryptic wing patterns.

European butterfly and caterpillarPhoto: Dr. F. Nemos

A butterfly has an enlarged humeral lobe on each hindwing, while a moth has a frenulum, which is a structure consisting of bristles or spines.

Butterflies do not have tiny hooks or bristles, which link forewing to hindwing in moths. A butterfly rests with wings closed, while a moth usually rests with its wings open.

Green mothPhoto: Saleem Hameed

Daytime Activity

Butterflies are active during the day (diurnal). Moths are active at dawn or dusk (crepuscular).

Moth cocoonPhoto: meganmccarty


Cocoons and chrysalids protect the pupa, which is the intermediate stage between the larva and adult. While a moth makes a cocoon wrapped in a silk covering, a butterfly makes a chrysalis, which is hard and smooth without a silk covering.

Butterfly pupae hang above ground from a branch or similar support. A moth pupae is found underground or on the ground.

There aren’t any simple characteristics to differentiate between butterfly caterpillars and pupae from those of moths according to Big Sky Institute at Montana State University.

Butterfly emerging chrysalis.jpgPhoto: Hustvedt

References: 1, 2, 3, 4, 5, Opler, Paul A., Kelly Lotts, and Thomas Naberhaus, coordinators. 2010. Butterflies and Moths of North America. Bozeman, MT: Big Sky Institute. 6