One of the most common questions we get at the butterfly garden where I work is, “How do I tell the difference between a moth and a butterfly?” Most people know that butterflies fly by day; moths fly at night - but there are exceptions as far as moths go; both wasp moths and hummingbird moths are day fliers. And if you only see the winged creature at rest, perched on a wall or something, then this rule doesn’t really help. Many people also note that butterflies tend to be more brightly colored, while moths are drab – but there are some fairly drab butterflies out there.
Fortunately, there are a few physical differences that can help you:
Antennae: Butterflies generally have long, thin antennae with club-shaped tips. Moth antenna are generally shorter and very feathery, as shown to the left. I find this to be the easiest indicator, although again, there are exceptions.
Wings at Rest: Resting butterflies generally fold their wings. Moths rest with their wings spread. This is a helpful way to tell them apart if you find one resting on a wall or hanging from a bush, but a butterfly basking in the sun or actively feeding will do so with its wings spread, so this trick doesn’t always work.
So, with those two rules in mind, take a look at the pictures below and see if you can tell which are moths and which are butterflies. (Click the image for a larger view.) Then scroll down for some more information, as well as the answers.
One of the most frequent butterfly vs. moth errors I hear (and for this we can thank the popular children’s book The Very Hungry Caterpillar) is that butterflies “spin a cocoon”. Actually, moth caterpillars create cocoons in which to metamorphose into moths. Butterflies don’t create any type of protective covering for their metamorphosis; they simply shed their last caterpillar skin and become a chrysalis, pronounced “kris-uh-lis”. (See it happen here.)
There are many more differences between moths and butterflies – if you’re interested, click here for more details. Before you go, here are the answers to the pictures above:
- A: Polyphemus Moth – Note the feathery antennae
- B: Common Buckeye Butterfly – The wings are spread because it’s feeding, but the antenna are slim.
- C: Least Skipperling Butterfly – The antenna are short, but have club-shaped ends.
- D: Io Moth – The wings are spread, and the antennae are feathery.
- E: Great Southern White Butterfly – Don’t let the drab colors fool you; the slim antenna and folded wings give this one away.
- F: Luna Moth – Size and shape aren’t good indicators, but the feathery antennae and open wings definitely are.
How did you do? Remember, these tips are not perfect – there are species that don’t fit the rules (wasp moths especially), but this should give you a pretty good start!