- Author: Kathy Keatley Garvey
They're curious little critters.
When solider beetles (family Cantharidae) go on patrol in your garden, don't kill them. They're not being deployed to harm you.
They're the good guys. They eat aphids and other soft-bodied insects.
Sometimes called "leatherwings"--they look like the insect equivalent to the British soldiers in the American Revolution soldiers--soldier beetles compete with lady beetles (aka ladybugs), lacewings, damsel bugs, long-legged flies and other insects for aphids. Larvae of lady beetles and syrphid flies (aka flower flies and hover flies) also feast on aphids.
The UC Statewide Integrated Pest Management Program (UC IPM) provides a good description of the soldier beetle:
"Adult soldier beetles are elongate and usually dark brown to black with orange, red, or yellow. The head is commonly bent downward. The antennae are 11-segmented, threadlike, and commonly held forward of the body. The pronotum is usually wider than the head and wider than long. The wing covers are smooth to velvety appearing and soft and flexible, giving rise to the common name leatherwings. Adults range from 1/16 to 1-1/8 inches (1.5 to 28 mm) long, varying by species....About 160 species of soldier beetles in 11 genera occur in California. Common genera include Cantharis, Chauliognathus, and Podabrus."
Adults are active during the day and usually observed on flowers or leaves infested with aphids or other honeydew-excreting insects," UC IPM says. "When disturbed, adults may withdraw their legs and drop to the ground as if dead. Adults' blackish and red coloration alerts vertebrate predators that cantharid beetles are distasteful; adults, larvae, and pupae can excrete noxious, defensive chemicals from specialized abdominal glands."
None that visited our garden last weekend dropped to the ground. We didn't disturb them, either (we were using a 200mm macro lens).
- Author: Kathy Keatley Garvey
The Red Coats are coming. The Red Coats are coming.
No, not an army of soldiers. Soldier beetles.
These insects (family Cantharida) resemble the uniforms of the British soldiers of the American Revolution, which is apparently how their name originated. They're also called "leatherwings" in reference to their leatherylike wing covers.
Soldier beetles are beneficial insects; they're the good guys and gals in the garden. The adults eat scores of aphids. In addition, they are pollinators. So, don't even think of killing soldier beetles. Enlist them in your garden to feast on aphids.
"The adults are long and narrow," according to the UC Statewide Integrated Pest Management Program (UC IPM), which labels them as natural enemies of garden pests. "Common species are often about 1/2 inch (13 mm) long with a red, orange or yellow head and abdomen and black, gray or brown soft wing covers. Adults are often observed feeding on aphids or on pollen or nectar on flowering shrubs and trees. Metamorphosis is complete. Larvae are dark, elongate, and flattened. They feed under bark or in soil or litter, primarily on eggs and larvae of beetles, butterflies, moths, and other insects. There are over 100 species of soldier beetles in California."
If you want to know identify some of the natural enemies of garden pests, you can download UC IPM's educational poster, "Meet the Beneficials: Natural Enemies of Gardens" here.
The poster illustrates some of the beneficial insects, mites and spiders that prey on garden pests:
- Convergent lady beetle
(adult, larva, eggs) - Green lacewing
(adult, larva, eggs) - Predaceous ground beetle
(adult, larva) - Assassin bug
- Pirate bug
- Damsel bug
- Soldier beetle
- Spiders
- Syrphid fly
(adult, larva) - Sixspotted thrips
- Western predatory mites
- Predatory wasps
- Praying mantids
- Examples of parasites (including a typical life cycle)
These soldier beetles may even know how to pull rank.