Moth ID: How to Identify a Moth From a Photo

• Antenna shape: moths typically have feathery or spindle-shaped antennae, unlike the slender, club-tipped antennae of butterflies.
• Contrast (butterflies): butterflies are day-active, brightly colored, and have long, thin antennae with a knob on the end.
• Resting posture: moths typically fold the front and hind wings over one another in a V-shape when at rest.
• Contrast (butterflies): butterflies typically hold their wings vertically together over the body when at rest.

People most often mix moths up with:

• Butterflies

Open the other page and compare its list against the marks above; the differences are usually in the antennae, wings or the way the body is divided.

In Kentucky gardens there are few pest butterfly species, but many moth pests.

Some moths (such as clothes moths) occur indoors and are usually found close to infested items, in dark areas such as closets.

Get as close as your camera will focus, from directly above, in daylight or a bright lamp. Include the whole body with the legs and antennae in frame; a second shot from the side shows wings and body segments. Put a coin or ruler next to it for scale. For a bite or a bug found on skin or bedding, photograph the bug itself, not the mark. The app names the likely group; use the list above to confirm.

A moth is a scale-winged insect in the order Lepidoptera, the same order as butterflies. Check three things:

• Wing scales. Moth wings are covered in scales. Caddisflies, the insects most often mistaken for moths, have hairy wings instead (Missouri Department of Conservation).
• Antennae. The University of Kentucky describes moth antennae as feathery or spindle-shaped; butterflies have long thin antennae with a knob at the end.
• Resting pose. Texas A&M entomologists note that most resting moths fold the front and hind wings over one another in a V shape, while butterflies more often hold them upright over the body.

Most moths fly at night and are dull-coloured (University of Kentucky), but not all: the Wildlife Trusts note that some species fly by day, especially on warm, sunny days.

Narrow it down in this order: where you found it, its size, its colour and pattern, and the date.

• Indoors, near wool, in a dark closet, fluttering rather than flying straight: likely a clothes moth. UC IPM gives the webbing clothes moth a wingspan of about 1/2 inch and a length of about 1/4 inch at rest, gold with reddish-gold hairs on top of the head; the casemaking clothes moth is browner with faint dark spots. Clothes moths are not attracted to lights.
• In the kitchen, near flour, cereal, nuts or dried fruit: likely a pantry moth. The Indianmeal moth is 1/3 to 2/5 inch long with a wingspan of about 3/5 inch; its forewings are reddish-brown with a coppery sheen on the outer two-thirds and whitish-grey near the body (UC IPM). UC IPM notes pantry moths are bigger and have less hair than clothes moths.
• On an outside wall near a light: a night-flying moth drawn in overnight. Texas A&M suggests checking walls lit by artificial light overnight to find moths in their natural resting poses.
• Visiting flowers by day: possibly a day-flying moth. The Wildlife Trusts give the six-spot burnet and cinnabar as examples, and the silver Y, which is easily disturbed from vegetation.
• Colour and pattern: the Wildlife Trusts sort moths by main colour (brown, black, orange, green, yellow, red), then by marks such as the black mark near the forewing tip of the large yellow underwing.
• Date: many moths fly only in certain months. The Wildlife Trusts give June to August for the swallow-tailed moth, with a second generation in September and October some years.

• Skippers are butterflies that are often taken for moths because of their short, chunky bodies. The Missouri Department of Conservation says nearly all skippers have club-tipped antennae bent like a hook, and about 275 species live north of Mexico. Geometrid moths also rest with their wings flat to the sides, but they have narrow bodies and no hooked clubs.
• Moth-butterflies (family Hedylidae) are small, brown butterflies that look like geometrid moths and lack clubbed antennae (Wikipedia's butterfly article).
• Caddisflies come to lights at night like moths. The Missouri Department of Conservation separates them by hairy rather than scaly forewings, thread-like antennae usually as long as the body, and wings held roof-like over the back.
• Butterflies at rest can be checked against butterflies.

Yes, you can identify a moth from a picture. Photograph it where it rests, without chasing it off: the natural resting pose, the top of the wings and the antennae are what an app or an expert compares. Take a second shot from the side if you can, and note the date and place. Texas A&M points out that field guides mostly show moths with wings spread flat as in museum collections, which is why a resting moth is hard to match to a book by eye; an identification app does that matching for you. Photograph it and InsectLens identifies it. For a second check, ButterflyIdentification.org lets you browse North American moths by state and compare two species side by side.