The beetles are coming!

No, this is not a historical reference to that famed rock band from Liverpool.

These are real beetles. The insects.

Lynn Kimsey, director of the UC Davis Bohart Museum of Entomology and a UC Davis distinguished professor of entomology, is fielding scores of calls--some panicked calls--about a beetle invasion in Davis.

In response, Kimsey has just created a public service announcement (PSA) of what they are (they are red flour beetles) and what folks should do and not do (don't panic).

"We have had a lot of reports and panic about small beetles invading people's houses in Stonegate and other parts of Davis," she relates on YouTube, "and just thought we ought to just clear the air a little bit with this and tell you a little about these guys. So as you can see they are very tiny.  These are grain beetles. They are called the red grain flour beetle." They are Tribolium castaneum.

"They feed on dried, starchy materials," she says. "They will even occasionally feed on things like raisins, but  nothing else. They are a stored product pest.  They are probably coming out of a field of grain--grain fields were harvested in the last month or so. So they are coming out of the fields and they are flying at night."

Kimsey points out that they "will come into homes because of the lights. Also, the north wind we had blowing for awhile that didn't help."

The fastest way to get rid of them? "Vacuum them up," Kimsey says. "Dispose of the bag. Don't spray because it won't do any good."

She also urges folks to store their flour and other grains in tight-fitting lidded plastic containers, which "will prevent beetles as well as meal moths and things like this from getting in and starting an infestation."

If you do find an infestation, Kimsey says, the "fastest way to take care of it is to either put the material that is infested in the freezer, throw it out, or put it in the sun.  It is still edible. These beetles are not harmful. They don't contaminate materials, unless you don't like eating beetles."

Kimsey also acknowledges it is "quite possible to get these beetles from a product you bring in from the store."

"And that happens," she says. "It is just one of those things. So what I would say is take a deep breath. This too shall pass."

Worldwide Pest
The red flour beetles are a worldwide pest of stored products. The adults are reddish brown, about 1/8th of an inch long, and oval and flattened in shape. They attack flour, cereals, pasta, biscuits, beans, and nuts, among other items, according to Wikipedia. "The United Nations, in a recent post-harvest compendium, estimated that Tribolium castaneum and Tribolium confusum, the confused flour beetle, are "the two most common secondary pests of all plant commodities in store throughout the world."

The females of both species are polyandrous, that is, they will mate with multiple different males.

The UC Statewide Integrated Pest Management Program (UC IPM) describes the red flour beetle (see photo of the red flour beetle) as a common pantry pest.

"Pantry pests usually enter your home in an infested package of food," UC IPM says. "You might not notice these small insects until you see moths flying around your kitchen or beetles crawling in your food. Get rid of these pests by removing infested food, tightly sealing stored dry food, and thoroughly cleaning the area."

UC IPM offers these tips on its website for preventing a pantry pest infestation:

• Store food in containers with tight-fitting lids, not plastic bags.
• Store bulk goods like pet food in airtight containers.
• Keep certain infrequently used food like flours, spices, and grains in a freezer if possible. 
• Wash old containers before filling them with new food.
• Don't mix old and new food together. 
• Clean shelves, bins, and other food storage areas regularly.

Meanwhile, listen to Professor Kimsey's PSA on YouTube and check out the images.

The beetles. They're not just coming. They are here. 

Do you know that today is "World Robber Fly Day?"

"World Robber Day?" you ask.

No, "World Robber Fly Day."

Among those celebrating this special day is doctoral candidate Charlotte Herbert Alberts of the Department of Entomology and Nematology, University of California, Davis, where she studies robber flies (Diptera: Asilidae) with distinguished professor Lynn Kimsey, director of the Bohart Museum of Entomology.

World Robber Day takes place every April 30. What's different this year? Well, the COVID-19 pandemic, for one. And she and husband George now have a darling baby boy, Griffin, born in April 2020.

Contrary to popular opinion, Griffin's first word was not "Asilidae." (It was "Hello.") And yes, his crib contains a robber fly, a gift crocheted by Rebecca Godwin of the Jason Bond lab. She is now an assistant professor of biology at Piedmont University, Demorest, Ga.

"I think the robber fly looks like a Holococephala sp.," Charlotte says.

In true entomological form, Griffin loves searching for insects and spiders in his family's back yard, and listening to his parents read him such books as  "An Introduction to Robber Flies and Their Allies of the Southwestern United States" by Rick Rogers.

Globally, there are more than 7500 described species of robber flies.  Most people have neither seen nor heard of the insects.  "This anonymity is probably due to a variety of reasons," she says. "Many people call them assassin flies because of their tendency to look like other insects, in particular, wasps or bumble bees." They are also territorial, with one or two individuals in a given area. "It can take a while to find your first robber fly, but once you do, you will start to see them all over the place!"

Where can you find them?  "Go into the woods and look for sunny spots with areas for the flies to perch on," Charlotte says. "They mostly perch on the flat surface of a leaf in the sun, or at the very tip of a pointy twig. From their perch, they can hunt for insect prey in flight. Once they spot prey, the assassin fly quickly intercepts it in flight and immediately pierces it with its hypodermic needle-like mouthparts to inject a paralytic neurotoxin to subdue it. Pre-digestive enzymes are also inserted to reduce the innards into a smoothie-like concoction, which the assassin fly feeds on through the needle-like hypopharynx."

"Despite being venomous and highly voracious predators, assassin flies are no danger to us! I caught my first assassin fly in the palm of my hand! Because they are top predators in their world, they are not very fearful of people. I routinely have had them perch on me to hunt prey. But be careful, some of the larger assassin flies can pierce the skin with a defensive bite if they are aggravated enough. Their bites have been compared to a honey bee sting."

Charlotte points out that "All insects play essential ecosystem roles that directly or indirectly affect our daily lives, whether through pollination, population control of pests, decomposition, product production, and more. Insects, and especially flies, face a stigma that is difficult to overcome. Assassin flies are a fantastic, charismatic example of a family of flies that are generally unknown by the public and yet is one of the most speciose and helpful in pest population control. I have regularly played with the idea of keeping a couple as house pets to control the other unwanted flying insects that make it into our house." 

Charlotte, whose major roles currently include entomologist, artist, wife and mother,  developed her love of entomology on the family farm in New Hampshire. She remembers her mother reading "Charlotte's Web" to her and being delighted that "a spider shared my name." The farm yielded scores of insects and spiders that fascinated her. "I couldn't understand why people hated spiders and insects so much. When handled gently and with love, they never bit or hurt me so I saw no reason to be scared of them...they were just misunderstood."

Little Griffin is following in her footsteps. Next year he'll probably say "Happy Robber Fly Day."

Or maybe "Happy Asilidae Day."

They're out there, and you don't have to crane your neck to see them.

Some folks mistakenly call them "mosquito hawks" or "mosquito eaters," but they are neither. They are crane flies,  members of the family Tipulidae of the order Diptera (flies).

They're everywhere. 

We've been seeing the slender, gangly, goofy-looking insects, Tipula oleracea, bump into walls and flower pots. This one (below) glided into the tower of jewels, Echium wildpretii, and just remained there for several minutes. 

Lynn Kimsey, director of the Bohart Museum of Entomology and UC Davis distinguished professor of entomology, emphasizes that they don't eat mosquitoes. "In fact, adult crane flies generally don't eat at all," she points out. "Their entire brief adult lives are spent searching for mates and laying eggs." Crane flies are attracted to lights at night and you may find them around your porch light.

"Adult crane flies emerge from the soil beneath turfgrass, pastures and other grassy areas in late summer and fall," according to the UC Statewide Integrated Pest Management Program, part of the UC Agriculture and Natural Resources.. "The adults have very long legs and resemble large mosquitoes. Females mate and lay eggs in grass within 24 hours of emerging. Eggs hatch into small, brown, wormlike larvae that have very tough skin and are commonly referred to as leatherjackets. The leatherjackets feed on the roots and crowns of clover and grass plants during the fall. They spend the winter as larvae in the soil; when the weather warms in spring, they resume feeding. During the day larvae mostly stay underground, but on damp, warm nights they come to the surface to feed on the aboveground parts of many plants. When mature, the larvae are about about 1 to 1½ inch long. Around mid-May they enter a nonfeeding pupal stage and remain just below the soil surface. In late summer, pupae wriggle to the surface and the adults emerge. There is one generation a year."

This one (below) didn't find a mate on the tower of jewels but it did find a towering view. The plant can reach 10 feet in height.

Butterflies and moths totally fascinate entomologist Jeff Smith, the 32-year volunteer curator of the Bohart Museum of Entomology's Lepidoptera collection. 

Smith loves talking about them, engaging folks face-to-face, and answering their questions. He is a fixture at the Bohart Museum open houses and other events, including the UC Davis Biodiversity Museum Day and the annual UC Davis Picnic Day.

But this year's Picnic Day, the 107th annual, went virtual due to the COVID-19 pandemic. Not to be deterred, Smith hosted a one-hour Zoom session. "Mimicry in the Butterflies and Moths with Jeff Smith," now available online on YouTube at https://youtu.be/8ZccezxhhK4.

Smith prefaced his talk by recommending the 375-page book, Insects and Other Arthropods of Tropical America by Paul E. Hanson and Kenji Nishida. "I didn't write it," he added, "and we (Bohart Museum) do not sell it (in the gift shop)." The book is an introduction to arthropods in North America--not just butterflies and moths but beetles, wasps, flies, true bugs and others.

"I've always been fascinated by the mimicry of  butterflies and moths," said Smith, who won a 2015 Award of Distinction from the UC Davis College of Agricultural and Environmental Sciences for his volunteer service (see news story).  "I've had the opportunity to make 10 to 12 trips to South and Central America. What I found there are great examples of how they can mimic each other or other things in order to survive." 

Smith defined mimicry as "the close resemblance of an animal to some other animal, some other a plant or some inanimate object." Müllerian mimicry, named for Johann Friedrich Theodor "Fritz" Müller, is "where two or more species have similar appearances as a shared protecting device," Smith told this audience. "Batesian mimicry, named for Henry Walter Bates, is the resemblance of an edible species to other species that are noxious and avoided by predators."

"The monarch and the viceroy are good Batesian mimics," Smith said, "because until recently, it was believed that the monarch is distasteful and slightly toxic and that the viceroy was an edible species but it looked so much like the monarch that it was protected as well. It turns out--I don't know if somebody ate it or if they just tested the chemicals in the insect--but it turns out the viceroy is also a distasteful and toxic butterfly so we've now switched this from Batesian and mimics to Müllerian mimics, but the fact is, that they they look very much alike. Predators may have tried one and didn't care for it so now they leave alone anything that kind of looks like that."

 "In order for mimicry to work," Smith pointed out, "the two different species need to be living in the same general habitat as each other. So if the monarch lived in Asia and the viceroy lived in North America, predators would never learn to associate these things with each other, and with that bad experience of trying to eat them."

"It's also important, I think, for us to understand that everything about every insect, in particular every butterfly and  moth, that every pattern, every color, and every shape is meant to protect it. These things have evolved over many millions of years and that's what's worked for them."

Smith called attention to camouflage: butterflies species that resemble leaves and moths that are perfectly camouflaged against a tree trunk.  Larvae of some butterflies, like the Anise swallowtail, Papilio zelicaon, resemble bird droppings, and offer some protection. When disturbed, the Anise caterpillar extends its osmaterium or scent glands "that are very smelly."

Smith also drew attention to predator avoidance of butterflies with eye spots, such as the buckeye butterfly, Junonia coenia, and the owl butterflies, Caligo. Some bumble bees have beetle and fly mimics, including the longhorned wood-boring beetles and robber flies. "They look like something that could sting and they get protection from that."

Smith estimated that of the 17,500 described species of butterflies in the world, about 750 of those occur in North America. "However, in North America there's 160,000, easily, species of moths. Moths are far more numerous than butterflies, and in particular, with the little tiny moths, it's estimated by experts in those groups, that at least 90 percent of the species still have not been described. They are sitting waiting for someone to identify them and give a name to them. So if anybody is interested in insects and wondering if there's still something left to do, the answer is absolutely yes."

The Lepidoptera curator also discussed host plants: how milkweed offers toxicity to monarch caterpillars, and how passionflower offers toxicity to Gulf Fritillaries.  "And they sequester it. They use it for their own defenses. It's kind of curious that in the monarch butterflies, the male may pass on some of those toxic chemicals to the female when they mate, and the female then stores those chemicals into the eggs, and gives the eggs some level of protection once they're placed on a plant. So they call it a nuptial gift."

"Red, orange and yellow tend to be warning colors," Smith related. "They've very common on insects that are toxic and distasteful, and therefore, their mimics also have these red, orange and yellow colors. A predator might leave them alone because (after eating one),  they are wired to know they don't taste good."

Tabatha Yang, the Bohart Museum's education and outreach coordinator, helped field the questions. Smith said Lawrence Allen's book, Butterflies of the Western States, available in the Bohart Museum's online gift shop, is  a good resource.

When asked his favorite butterfly, Smith acknowledged that "it's kind of hard to pick a favorite butterfly. It may very well be, I mean as far as the thing that gets me the most excited, the big Morphos, the big blue Morpho butterflies that you find in tropical America. There are about 30 different species. They're almost all brilliant metallic blue on top, with wing spans of four to six inches across, and brown on the underside so they're camouflaged when they're landing with those wings closed. But when you see one of those fly by you, and when you're walking around in a trail in the rain forest in Central or South America, it's pretty exciting. Once in a while, it'll even land on your arm and sip the the sweat."

Many people don't want to know this, Smith said, but butterflies also feed on the nutrients in "rotten bananas, dead animals, and urine and feces." That includes human waste.

Lamenting the plunging population of monarchs, Smith advocated that folks plant milkweed and nectar sources in their gardens.  Urbanization is one of the causes of the decline, he said.

The Bohart Museum, which is marking its 75th anniversary this year, is located in Room 1124 of the Academic Surge Building on Crocker Lane, but is temporarily closed due to the COVID-19 pandemic.  Directed by Lynn Kimsey, UC Davis distinguished professor of entomology, it houses nearly eight million insect specimens and is the seventh largest insect museum in North America. In addition to its online gift shop, the Bohart Museum maintains a live "petting zoo" comprised of Madagascar hissing cockroaches, stick insects and tarantulas.

In 2019, UC Davis hosted the international Lepidopterists' Society's 65th annual conference. The scientists visited the Bohart Museum twice. Kimsey participated with senior museum scientist Steve Heydon; and Bohart associates retired research entomologist John De Benedictus, naturalist Greg Kareofelas, and Smith. (See Bug Squad blog)