Tag Archives: moths

Butterflies and Moths: Busting the Myths

Distinguishing a moth from a butterfly should be easy, right? Well, it may be harder than you think. Butterflies are renowned for their bright colors, and moths have a reputation for drabness and nighttime flight—but many don’t fit this pattern.

Butterflies and moths are very closely related, and belong to the scientific order Lepidoptera. Though butterflies may steal the show in your garden, there are far more moth species than butterfly species. Here are four helpful tips for telling them apart.

1. Color isn’t everything: Some butterflies are dull and some moths are colorful.

There are plenty of bright, showy butterflies, but many of our local species have subdued hues. This common ringlet (Coenonympha tullia) is a good example.

Common ringlet

Common ringlet

And while it’s true that most moths aren’t as colorful as butterflies (bright colors aren’t as visible at night when many moths are active), there are plenty of exceptions. Here in Massachusetts you’ll find moths in a rainbow of hues. Just look at the rosy maple moth (Dryocampa rubicunda).

Rosy maple moth via Patrick Coin/Flickr

Rosy maple moth via Patrick Coin/Flickr

2. Most moths fly only at night—but some fly during the day.

You’ll usually see butterflies flying during the day, and moths at night. But beware—some moths are active in the daytime. A few, such as this snowberry clearwing (Hemaris diffinis), will even visit flowers alongside butterflies and hummingbirds. Learn more about these hummingbird moths.

Snowberry clearwing moth

Snowberry clearwing moth

3. Many butterflies hold their wings together vertically, whereas most moths don’t.

This mourning cloak (Nymphalis antiopa) is holding its wings together above its back in a pose more typical of butterflies.

Mourning cloak

Mourning cloak

Moths, on the other hand, tend to assume one of two poses. They’ll either rest with their wings held to the sides, as in this common lytrosis (Lytrosis unitaria)…

common lytrosis

Common lytrosis

…or with their wings laid against their backs, as in this banded tussock moth (Lophocampa tessellaris).

Banded tussock moth

Banded tussock moth

But there are exceptions. Some butterflies will even hold their wings in a confusing mix of horizontal and upright, as in this dun skipper (Euphyes vestris).

Dun skipper via John Beetham/Flickr

Dun skipper via John Beetham/Flickr

4. One of the best ways to tell them apart is to look at their antennae.

All butterflies and moths have antennae—a pair of long sensory organs between their eyes. In most butterflies there’s either a thickened club or hook shape at the end. Check out the black blobs on the antennae on this silver-bordered fritillary (Boloria selene).

Silver-bordered fritillary

Silver-bordered fritillary

The antennae of moths lack these thickened tips. Also, some are covered with little projections, making them look like combs or feathers, as in this non-native gypsy moth (Lymantria dispar dispar).

Gypsy moth

Gypsy moth

Now it’s time to test yourself. Can you tell if this is a moth or a butterfly?

Butterfly or Moth?

If you guessed butterfly, you’re right. This Juvenal’s duskywing (Erynnis juvenalis) isn’t the most colorful insect, and it tends to lay its wings flat. However, the ends of its antennae are thickened (in this case, they’re hook-shaped).

For more on the amazing members of Lepidoptera, join one of our butterfly and moth programs.

The Secret Life of a Giant Silk Moth

Cecropia MothIf you’re under the impression that moths are dull creatures who eat holes in sweaters, you haven’t encountered a giant silk moth. Luna moths, Promethea moths, Polyphemous moths, and Cecropia moths are all native silk moths of the subfamily Saturniinae.

These amazingly large, stunningly beautiful moths are found throughout Massachusetts, but we rarely see them. Flying mostly at night and spending much of their lives as caterpillars and cocoons, these moths fly under the radar. Observing one in action is always a WOW experience.

Life Cycle of The Cecropia Moth

In late May and early June, adult Cecropia moths (pictured above) emerge from their cocoons. With a wingspan of 5 to 6 inches, the Cecropia moth is the largest moth in North America. Adults are born without mouth parts, do not feed, and have one job: to mate and reproduce. Males have large feathery antenna, which can pick up the scent of a female from a mile away.

After mating, females lay more than a hundred eggs, usually in small rows on the underside of leaves. Around 10 to 14 days later, tiny black caterpillars emerge. The caterpillars are eating machines and feed on the leaves of many common trees including cherry (a favorite), sassafras, lilac, ash, apple, poplar, and willow.

Cecropia Eggs

The caterpillars go through 5 instars (i.e., skin sheddings), and grow very large. By the 5th instar they’re often at least 4 inches long and thicker than an adult thumb. They are also remarkable looking, with a frosted green coloring and red, blue, and yellow knobs extending from their bodies. Children often remark that it looks like ladybugs are riding on the caterpillar’s heads!

Cecropia Caterpillars - Cara Yacino

The caterpillars have many enemies and mortality rates are high. After weeks of eating and growing, the rare caterpillar that has successfully reached the 5th instar is ready to cocoon. On a branch or twig, the caterpillar will spin a rough, brown, spindle-shaped cocoon. The caterpillar will spend the winter in the cocoon, transforming into an adult moth, ready to emerge in late spring.

Cecropia Moth Cocoons

Status of Cecropias

Sadly, Cecropia moth numbers appear to be in decline due to habitat loss, pesticide use, and parasitism by a tachinid fly introduced to control the Gypsy Moth. (See Boettner et al, 2000). Maintaining a pesticide-free yard full of native plants and natural spaces is one way to help these amazing creatures. Some people go a step further and raise silk moths to increase their numbers, a labor-intensive and rewarding experience.

Learn More

Join a mothing or insect program at a Mass Audubon wildlife sanctuary near you.