Golden Tortoise Beetle

The golden tortoise beetle is a tiny leaf beetle that looks like a drop of shiny gold. It lives in North America and feeds on morning glories and their relatives. Its most amazing trick is that it can change color, from gleaming gold to dull reddish-brown, in just a few minutes.

Golden tortoise beetle Quick Facts

Common name	Golden tortoise beetle
Scientific name	Charidotella sexpunctata
Kingdom	Animalia
Phylum	Arthropoda
Class	Insecta
Order	Coleoptera
Family	Chrysomelidae
Genus	Charidotella
Type	Insect (leaf beetle)
Diet	Herbivore: morning glory, bindweed and sweet potato leaves
Habitat	Gardens, fields, roadsides
Native range	North America
Size	5-7 mm long
Colours	Metallic gold; dull reddish-brown with black spots when disturbed
Special feature	Can change color in minutes

What does the golden tortoise beetle look like?

This little beetle is only about 5 to 7 mm (around a quarter of an inch) long, about the size of a ladybug. Its body is round and flat, and the edges of its wing covers and thorax spread out into a wide, see-through rim, like the brim of a hat. When the beetle pulls in its legs and head, this rim hides them completely, a bit like a tortoise hiding in its shell. That is how all tortoise beetles got their name.

Healthy, calm golden tortoise beetles are a brilliant metallic gold, which is why people sometimes call them “goldbugs”. The clear rim lets you see the leaf underneath.

How does it change color?

The gold shine is not made by pigment. It comes from thin layers in the beetle’s outer skin (cuticle) that hold tiny amounts of moisture and reflect light like a mirror. When the beetle is disturbed, for example when it is touched, it can change the amount of liquid in these layers. The shine disappears and the beetle turns a dull orange or reddish-brown with black spots, making it look less like a tasty treat.

When it calms down, the gold comes back. The color can also change as the beetle gets older or when it is mating. Sadly, dead golden tortoise beetles lose their shine for good, so collectors cannot keep their golden color in a display box.

Where does it live?

The golden tortoise beetle is native to the Americas and is common across much of the eastern and central United States and southern Canada. You will find it in gardens, fields, roadsides and waste ground, anywhere its food plants grow.

What does it eat?

Both adults and larvae eat the leaves of plants in the morning glory family. Their favorites are morning glories, bindweeds and sweet potato plants. They usually feed on the underside of the leaf, chewing small, round or irregular holes.

This beetle is a picky eater. You won’t find it munching on thistles or nettles; it sticks to the morning glory family.

Life cycle

Like all beetles, the golden tortoise beetle goes through complete metamorphosis: egg, larva, pupa and adult.

• Eggs. The female lays small, flat, whitish eggs, about 1 mm long, on the underside of leaves or on stems, often in small groups. They hatch in about 5 to 10 days.
• Larvae. The larvae are flat, spiny and brownish or yellowish. They feed for about two to three weeks.
• Pupae. The larva fastens itself to a leaf and becomes a spiny pupa. About a week or two later, the adult beetle comes out.
• Adults. The whole journey from egg to adult takes roughly a month to six weeks in warm weather.

Adults spend the winter resting in leaf litter and other sheltered places, a resting state called diapause. They come out in late spring to feed and lay eggs. In cooler northern areas there may be just one generation a year; in warmer places there can be more.

The larva’s poop umbrella

The larvae have a strange but clever way to protect themselves. At the tip of the abdomen is a forked tail called an anal fork. The larva piles its own droppings (called frass) and its old shed skins onto this fork and holds the pile over its back like an umbrella.

This “fecal shield” hides the larva and makes it look like a messy blob instead of a meal. The larva can also wave the shield at small predators, such as ants, to push them away. It does not help much against bigger hunters, such as predatory bugs that can pierce through it.

Is it a garden pest?

Golden tortoise beetles do chew holes in sweet potato leaves, but they rarely cause serious damage. Most gardeners see them as harmless, and some even enjoy them because they also feed on bindweed, a weed that many gardeners struggle with.

If there are too many on your sweet potatoes, simply pick them off by hand or knock them into a jar of soapy water. Pulling up nearby wild morning glories and bindweed also gives them fewer places to breed. There is usually no need for sprays.

Related: Burdock

Golden tortoise beetle FAQs