Soldier Beetles

Soldier beetles rank right up there with lady beetles and lacewings in the world  of beneficial insects.


Soldier beetles are predators that love to eat aphids. For that, alone, they are loved by gardeners. They also help pollinate crops as they feed on pollen and nectar. Soldier beetle larvae love to eat the eggs and larvae of moths and butterflies, beetles, armyworms, and other insect pests.

Adult soldier beetle (Kate Russell)

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Soldier beetle identification​

Unlike many hard-shelled beetles, soldier beetles have softer, more leathery bodies. In fact, some people call them leatherwings. There are many different species of soldier beetles (Cantharidae), but they all have rather long, narrow, rectangular bodies that are approximately 1/2 inch long. They commonly have a red, orange, or yellow head, back and abdomen, with dark grey or brown wing covers. You will see a large dark spot on the wings, when open. The larva are long, flat, and dark colored. Larva are often found under bark and in leaf litter.


California is home to more than 100 different species of soldier beetle. There is another bug with an almost identical name, spined soldier bug (Good Guy), but they look more like brown marmorated stinkbugs (Bad Guys). If you look closely in the garden, you will see these soldier beetle lookalikes:

• Blister beetle species can look a lot like soldier beetles, but they have spots or stripes on their wing covers. Blister beetles can give you, well, blisters, so squash them with care before they start chewing on flowers and leaves. Blister beetles are the source of the infamous ‘Spanish fly’ and their toxin is used to treat warts.
• Red longhorn beetles look similar to soldier beetles, but they have more rounded reddish-orange wing covers and black heads. Adults eat pollen and nectar, and larva eat rotting wood, so there’s no need to do anything about red longhorn beetles.
• Lightning bugs aren’t found in San Jose, California., but they look a lot like soldier beetles. The only real difference is that you cannot see any portion of a lightning bug’s neck.

Encourage soldier beetles in your garden by:

• Avoiding the use of broad spectrum pesticides and insecticides
• Install plants that provide pollen and nectar
• Keep ants out of pest-infested plants
• Plant bright-colored flowers such as zinnia, goldenrod, and marigold
• Plant a linden tree