Brown Leatherwing

Brown Leatherwing Beetle
Location: Northern California
May 3, 2011 3:03 am
Dear Bugman,
I have noticed a different kind of bug hanging around my house and was very curious on what kind of bug it was. I took a picture of this bug and started researching the bug. I located the identification of the bug on your web page; Brown Leatherwing Beetle. I would like to know what this beetle likes to eat and if it will harm or damage anything? I would also like to know where the beetle likes to lay it’s eggs?
Signature: ~Mel

Hi Mel,
The Brown Leatherwing, Pacificanthia consors, is a common California species, and this year they seem to be more numerous.  They are also attracted to lights, so they are frequently encountered by humans, however, our typical sources, BugGuide and the Insects of the Los Angeles Basin, a book by Charles Hogue, do not provide information on the life cycle, though both agree that this is not a harmful species.  We did locate some wonderful information on the Pacific Horticulture website.  Frédérique Lavoipierre, Garden Ecologist writes:  “In his detailed and fascinating 1964 book, Beneficial Insects, Lester Swan comments on several beneficial species of soldier beetles and their associated prey, then notes that, unfortunately, they have not been studied extensively. Not much has changed in the ensuing four decades. ‘Oh, those! I have them in my garden, but I didn’t know they were beneficial,’ is the now familiar response when I point them out to garden visitors. Yet soldier beetles surely warrant the same recognition given to lady beetles and lacewings. In suitable habitat, they are a reliable and valuable ally. It is far easier to supply ideal living conditions for soldier beetles in gardens than in agricultural fields. This lack of potential for commercial use may help explain why soldier beetles have been so little studied, despite a voracious appetite for aphids, caterpillars, grasshopper eggs, mites, and other small pests. They are even reputed to attack cucumber beetles—reason enough for gardeners to agree that soldier beetles deserve further study!”  We are thoroughly charmed by the Pacific Horticulture website, and we fear for the longevity of information that is provided on the internet because websites come and go.  At the risk of getting dinged for copyright infringement, we feel compelled to directly quote more of the information provided by Frédérique Lavoipierre including this information on mating rituals:  “The female soldier beetle sometimes attracts hordes of males with the pheromones she emits, but generally only one male is successful. Most beetles don’t engage in elaborate courtship behaviors, but some soldier beetle males may ‘nibble’ females. Considering that soldier beetles usually only mate once, when there are a lot of these beetles in the garden, there seems to be a lot of ‘nibbling’ taking place! Since each female has a huge supply of eggs, building up good garden populations need not take a long time. The nocturnal larvae hatch in spring and are found in damp areas beneath rocks, in leaf litter, or under bark, where they prey on insects and other small organisms. A year or more after hatching, the larvae pupate and emerge as adults.
Soldier beetles have a varied diet, feeding on aphids and other homopterans, grasshopper eggs, caterpillars, root maggots and other soft-bodied insects. Many genera of soldier beetles, such as Cantharis, Podabrus, and Pacificanthia, are primarily carnivorous in both the larval and adult stage, but a few are minor pests in the larval stage, feeding on roots. Larvae primarily eat eggs and larvae of beetles, moths, grasshoppers, and other insects. Adults are frequently found on a variety of flowers, where they feed on pollen and nectar in addition to insect prey such as aphids and mealybugs. Because they are generalist predators, soldier beetles may also eat beneficial insects, such as lacewing larvae and aphids that have been parasitized by wasps.”  Finally, the Pacific Horticulture website provides this sage gardening wisdom:  “Encouraging a resident population of soldier beetles is easy in gardens. Choose suitable flowers to bloom over a long season. Any habitat garden must include a water source; soldier beetles are particularly known to frequent moist habitats. It is important to the life cycle of soldier beetles (and many other beneficial organisms) that they have undisturbed, mulched soil in which to pupate, so include permanent perennial plantings in gardens. A fragile and important community thrives at the interface between soil and organic matter. In permanent plantings, avoid raking and add organic material to the surface of the beds as needed to keep the soil in good fertility.”