Bug o’the Week – Southern Corn Billbug

Bug o’the Week
by Kate Redmond

Bug o’the Week Southern Corn Billbug

Greetings, BugFans,

As Seasoned BugFans know, the BugLady is a fan of weevils – she loves the cut of their tiny jibs (for “jibs” read “snouts”) (for “snouts” read “rostrums”).  Snouts tipped with chewing mouthparts and adorned with clubbed and elbowed antennae https://bugguide.net/node/view/1038921/bgimage, snouts long and slender https://bugguide.net/node/view/2308802/bgimage, and snouts short and stout https://bugguide.net/node/view/2003970/bgimagehttps://bugguide.net/node/view/1959459/bgpage.  So she was excited to find a Southern corn billbug while she was in a park on the Milwaukee River – an odd spot, but you’re never far from a corn field in Wisconsin.

Who are the billbugs?  They are members of the beetle order Coleoptera, the largest order in the whole animal kingdom with about 390,000 described species (the Coleoptera account for about 40% of all insect species), and of the beetle family Curculionidae (the bark and snout beetles), the largest family in the whole animal kingdom, with 50,000 species worldwide.  As British biologist J.B.S. Haldane (may have) said, the Creator had “an inordinate fondness for beetles.”  Billbugs, so-named for their curved snouts, are weevils in the genus Sphenophorus (from the Greek for “wedge-bearer”), with 65 species in North America and more elsewhere.

As a group, Billbugs are persona non grata because of the habit of many species, mainly in the larval stage, of feeding on members of the grass family.  Billbugs tend to be pedestrians – they’ve been observed in flight, but not very high and not for very long (and with a tailwind), and their larvae are legless, which means that they don’t disperse quickly.   

Despite their name, SOUTHERN CORN BILLBUGS(Sphenophorus callosus) are notably absent from much of the South https://bugguide.net/node/view/278604/data.  The North Carolina University Extension describes their range thus: “the Coastal Plain of the Carolinas and Georgia. However, this pest damages corn over the entire Coastal Plain of the southern states and up the Mississippi River valley into the Midwest.”  Their name doesn’t seem to set off any alarms with University Extension offices here in Wisconsin.

Southern corn billbugs are a little more than one-third of an inch long and are a little lumpy-looking.  Some are brownish in color https://bugguide.net/node/view/1933001/bgimage, and they often carry a coating of dust or dirt.  Here’s a glamour shot – https://bugguide.net/node/view/77598/bgimage.  

While many billbugs go for turfgrass and some attack rice, Southern corn billbugs specialize in corn (rice and corn are members of the grass family).  It’s a one-two punch – the larvae feed at the base of the plant, and the adults feed higher up, and the “jaws” at the ends of the adults’ snouts allow them to reach into the inner tissues of the stem.  Adults like several other plants, like sorghum (another grass), and they especially like Yellow nut sedge, aka Chufa, a maybe-native-maybe-not sedge that’s considered an invasive agricultural weed (click on any picture for a slide show https://www.minnesotawildflowers.info/grass-sedge-rush/yellow-nutsedge). 

Southern corn billbugs overwinter as adults in leaf litter or barely underground, often in ditches and hedgerows near corn fields.  They emerge as the young corn emerges and trek into the field (they also float well), and they’re more likely to be found in corn plants around the periphery of a field than the interior. 

Females lay eggs toward the base of the corn stem, in holes they made while feeding.  When the larvae hatch (just one per stem, but there may be as many as five in a stem if billbugs are thick on the ground), they move down the outside of the stem and feed in the roots and then bore into the lower stalk.  Needless to say, this makes it hard for the young plant to thrive.  They pupate in cells in the corn stalk or root, or in the soil.  Newly-minted adults may emerge to feed before tucking in for the winter, or they may hunker down until spring.    

Rotating crops keeps billbug numbers down, and farmers who practice continuous no-till agriculture have higher infestations.  One potential biological control is (Science Word of the Week) entomopathogenic nematodes.  Nematodes are small roundworms that are, according to Britannica, “among the most abundant animals on earth.”  Nematodes are – well – everywhere (https://uwm.edu/field-station/bug-of-the-week/nematodes-for-poets/).  Entomopathogenic (pronounced just like it looks) means that the nematodes are able to cause disease in the billbug larvae or other insects they encounter. 

According to the University of Florida’s Featured Creatures page on the topic, “Entomopathogenic nematodes occur naturally in soil environments and locate their host in response to carbon dioxide, vibration and other chemical cues.”  A nematode carrying symbiotic bacteria (bacteria that it lives peaceably with) enters the larva’s body cavity and bacteria are released there.  The bacteria multiply, the larva dies, and the nematode feeds, matures, and reproduces within. 

The BugLady can’t recall if she’s shared this dynamite article about the decline of insects.  Great graphics!  https://www.reuters.com/graphics/GLOBAL-ENVIRONMENT/INSECT-APOCALYPSE/egpbykdxjvq/

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Bug o’the Week – Sculptured Resin Bee

Bug o’the Week
by Kate Redmond

Bug o’the Week Wildflower Watch – Swamp Milkweed

Howdy, BugFans,

BugFan Freda found and photographed this awesome bee in her pollinator garden in August.  It’s a distinctive bee, and it has an interesting story.

The Sculptured resin bee is sometimes called the Giant Asian resin bee, but there are resin bees that are larger, and it’s not just in Asia anymore.  It’s in the family Megachilidae – the Leafcutter, Mason, Resin, Mortar, Sharptail, and Woolcarder bees.

Megachilids tend to be sturdy, medium-sized, mostly solitary bees that carry pollen in a mat of hairs called a scopa on the underside of their abdomen rather than on their legs like honey and bumble bees.  They make egg chambers for their eventual young in pre-existing holes in the ground or in wood or other materials, and, depending on what group they’re in, they line the tunnels and seal the chambers with bits of leaf, plant resin, mud, or plant fibers (except for the Sharptail bees, Cuckoo leafcutter bees in the genus Coelioxys, which parasitize the nests of their Megachilid sisters).  Adults eat pollen and nectar, and they provision their egg chambers with pollen.  In many ways, the modus operandi of the Sculptured resin bee is similar to that of other family members.

Sculptured resin bees (Megachile sculpturalis) are big/“giant” bees (females measure about an inch and males are smaller) with elongated bodies and with big jaws that they use to collect plant resins https://bugguide.net/node/view/532857/bgimage (Megachile means “large jaws,”).  Males have a yellow moustache on their face https://bugguide.net/node/view/1689549/bgimage.  When they’re sitting on flowers, they hold their wings out to the sides in a “V.”  According to one source, the “sculptured” part refers to the head https://www.marylandbiodiversity.com/view/3314

They’re big and they look dangerous, but males can’t sting and although females can, they’d rather flee than fight (although one source mentioned that he was bitten rather sharply when he handled one, so…..don’t).   

They don’t come from here.  They’re native to Japan and parts of eastern Asia, and they arrived on our shores (North Carolina), probably in wood, in 1994.  They expanded their range to Alabama (1999), Canada (2002), Wisconsin (2004), Maine and Kansas (2008), and now they’re found in most states east of the Mississippi and a few that are west.  They’ve also found their way to Europe.  They like temperate zones, and researchers believe that they are likely to continue expanding throughout them.  Ecologists list their status as “adventive” – non-native and present but not established.   

The Megachilids are important pollinators, and Sculptured resin bees are no exception.  Like other Megachilids, Sculptured resin bees are (Cool Science Word #1) “polylectic” – they collect pollen from a wide variety of flowers (43 species in the US).    

Male Sculptured resin bees create territories and chase other males out of them.  About the genus Megachilebugguide.net says “The males of most species have enlarged light-colored front legs with a fringe of hairs and with odor glands. They use these features during mating. They partially cover the female’s eyes with the hairy legs and the odor glands are placed close to the female’s antennae” https://bugguide.net/node/view/1992972/bgimage.

Sculptured resin bees are (Cool Science Word #2) a xylophilous (wood-loving) bee.  Females create brood chambers in existing holes and crevices because although her large jaws are great for collecting resin and sap, they’re not so great for excavating in wood.  The cells are formed from wood particles, mud, and plant resin and filled with pollen, and when she’s satisfied with the job, she lays an egg on the pollen, seals the cell, and starts making another, often constructing 8 or 10 cells per tunnel.  The outside entrance to the tunnel may be sealed with a resin or mud cover.  Even though she is a solitary bee, she will tolerate other bees nesting nearby.  Her larvae feed in their cells throughout winter, pupate in them the following spring, and emerge in summer. 

So – is the Sculptured resin bee a good thing or a bad thing? 

Initial reactions were, “Hey – neat bee; it doesn’t seem to be bothering anything,” but any alien species has, of course, the potential to impact native species, whether through competition or spreading disease.  Sculptured resin bees can be hard on the flowers they visit; there are reports of the bee damaging flower petals while foraging for pollen and nectar in a way that may make it harder for native bees to pollinate them. 

Yes, they are pollinators, but researchers have noted that, like many non-native pollinators, they visit native plants, but they prefer non-native plants that hail from their areas of origin (one of the plants they pollinate in the South is Kudzu).

And then there are the nest tunnels.  Sculptured resin bees mostly use deserted tunnels, but not always.  They’re known to evict Eastern carpenter bees from their nest tunnels rather aggressively and then to redecorate the brood chambers for their own eggs.  There’s a potential for similar conflict with any bee that makes a similar-sized tunnel, and they can monopolize bee hotels (some experts recommend destroying Sculptured resin bee larvae in bee hotels).  One source noted that they have been observed killing honey bees.  

Time will tell.

On a Lepidopteran note, it’s Wooly Bear season.  Here’s the wooly bear BOTW, and a link to this year’s wooly bear celebration in Banner Elk, NC https://uwm.edu/field-station/bug-of-the-week/wooly-bear-caterpillar-re-do/

https://www.smithsonianmag.com/travel/groundhogs-are-old-news-in-this-tiny-town-caterpillars-predict-the-weather-180983146/

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Bug o’the Week – Wildflower Watch – Swamp Milkweed

Bug o’the Week
by Kate Redmond

Bug o’the Week Wildflower Watch – Swamp Milkweed

Howdy, BugFans,

The BugLady is already fantasizing about warm, sunny days in a wetland, photographing Swamp milkweed (and dragonflies), because she loves its color, and she loves being in wetlands, and because it’s a very busy plant, indeed!

Also called rose or red milkweed (there are a couple of species of southern milkweeds that are also called red milkweed), white Indian hemp, water nerve-root, and water silkweed, Swamp milkweed prefers damp soils and full sun near the water’s edge.

Indians, and later, the European settlers, used it medicinally (a tea made from the roots was reputed to “drive the worms from a person in one hour’s time”).  It was used with caution – its sap is poisonous – and the cardiac glycosides that protect Monarchs also deter mammals from grazing on all but the very young plants.  The fibers in its stem were twisted into rope and twine and were used in textiles.

Its flowers are typical milkweed flowers – a corona of five parts (hoods) with curved petals below and curved, nectar-secreting horns above.  The flowers are tricky – sticky, golden, saddlebag-shaped pollinia are hidden behind what one author calls a trap door (a stigmatic slit).  Insects walk around on the flower head, and when one of their feet slips through the slit by chance, a pollinium sticks to it.  When the bug encounters a stigmatic slit on the next plant it visits, the pollen is inadvertently delivered.  A quick-and-dirty, pick-up and delivery is what the plant had in mind; but, like the story of the raccoon (or was it a monkey) that reaches into the jar for a candy bar and then can’t pull its fist out of the small opening, sometimes the insect’s foot gets stuck to pollinia inside the trap door.  Insects that can’t free themselves will die dangling from the flower, and insects that escape may be gummed up by the waxy structures.  Look carefully for pollinia in the pictures.

Milkweeds support complex communities of invertebrates – their nectar attracts ants, bugs, beetles, flies, butterflies, moths, bees, and wasps, plus predators looking for a meal.  Here are some of the insects that the BugLady sees on Swamp milkweed.

TWO-BANDED PETROPHILA MOTHS (Petrophila bifascialis) are delicate moths that lead a double life.  By day, they sit sedately on streamside vegetation.  By night, the female crawls down the side of a rock into the water – sometimes several feet down – to deposit her eggs on the stream bottom, breathing air that she brings with her, held against her ventral surface (“Petrophila” means “rock-lover”).  Her larvae eventually attach themselves to a rock and spin a net to keep themselves there, feeding on diatoms and algae that they harvest from the rock’s surface with their mandibles. 

MULBERRY WING SKIPPER – A small (one-inch-ish wingspan) butterfly of wetlands with an arrow or airplane-shaped marking on its rich, chestnut-brown underwings (the upper surface of its wings looks completely different https://bugguide.net/node/view/34033/bgimage.  Adults fly slowly through low vegetation, where females lay their eggs on the leaves of sedges. 

FLOWER LONGHORN BEETLE BRACHYLEPTURA CHAMPLAINI (no common name), on a Swamp milkweed leaf.  Other than a “present” checkoff in a variety of natural area insect surveys, there’s just about nothing online about this beetle, and not much more in Evans’ book, Beetles of Eastern North America.  It’s a long-horned beetle in the Flower longhorn subfamily Lepturinae, a group that feeds on pollen in the daytime.  This one has pollinia on its mouthparts.

AMBUSH BUG – The dangling bee in this picture did not fall victim to the sticky pollinia (though it has plenty of them on its legs).  A well-camouflaged ambush bug snagged it as it visited the flower. 

SOLDIER BEETLE – These guys drive the BugLady crazy.  They’re lightning beetle mimics, and they’re pretty good at it, and she always overthinks the ID.  She doesn’t know why they’re imitating the closely-related lightning beetles – alarmed lightning beetles discharge poisonous blood/hemolymph from their leg joints, but alarmed soldier beetles do, too. 

CRAB SPIDER –This Goldenrod crab spider tucked itself down between the milkweed flowers and ambushed an Odontomyia soldier fly https://bugguide.net/node/view/417289/bgimage.

LARGE MILKWEED BUG – What a beauty!  Large milkweed bugs are seed bugs – they feed by poking their beaklike mouthparts through the shell of a milkweed pod and sucking nutrients from the seeds.  They don’t harm the plant (just the seed crop), and they don’t harm monarch caterpillars, either.  Like other milkweed feeders, they sport aposematic (warning) colors to inform predators of their unpalatability.  Large milkweed bugs don’t like northern winters and are migratory – like monarchs, the shortening day lengths, the lowering angle of the sun, and increasingly tough milkweed leaves signal that it’s time to go, and they travel south to find fresher greens.  Their descendants head north in spring.

MONARCH CATERPILLAR – Common milkweed and Swamp milkweed are Monarch butterflies’ top picks for egg laying. 

GREAT-SPANGLED FRITILLARY – The other big, orange butterfly.  Adults enjoy milkweeds and a variety of other wildflowers, and their caterpillars feed on violets – if they’re lucky enough to connect with some.  Females lay eggs in fall, near, but not necessarily on, violets, and the caterpillars emerge soon afterward.  They drink water but they don’t eat; they aestivate through winter in the leaf litter and awake in spring to look for their emerging host plants.

GIANT SWALLOWTAIL – A southern butterfly that seems to be getting a foothold in Wisconsin.  The book says they are annual migrants that produce a generation here in summer and that their caterpillars can’t tolerate Wisconsin winters, but the BugLady has seen very fresh-looking Giant Swallowtails here in May that didn’t look like they had just been on a long flight.  Their caterpillars are called Orange Dogs in the South, because their host plants are in the Rue/Citrus family Rutaceae.  In this neck of the woods, females lay their eggs on Prickly ash, a small shrub that’s the northernmost member of that family. 

CINNAMON CLEARWING MOTH – A nectar-sipper but, since it doesn’t land, not a serious pollinator.

NORTHERN PAPER WASP – Butterflies love Swamp Milkweed, and so do wasps.  The Northern paper wasp is the social wasp that makes a smallish (usually fewer than 200 inhabitants) open-celled, down-facing, stemmed nest https://bugguide.net/node/view/1411890/bgimage.  “Northern” is a misnomer – they’re found from Canada through Texas and from the Atlantic well into the Great Plains.  Her super power is chewing on cellulose material, mixing it with saliva, and creating paper pulp.  She may be on the swamp milkweed to get pollen and nectar for herself or to collect small invertebrates to feed to the colony’s larvae.  Curious about Northern paper wasps?  See https://bugeric.blogspot.com/2010/09/wasp-wednesday-northern-paper-wasp.html.

Also seen were ants, leafcutter bees, sweat bees, Great black wasps, Great golden digger wasps, Red soldier beetles, Fiery and Broad-winged Skipper butterflies, and Thick-headed flies.  

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Bug o’the Week – And Now for Something a Little Different XVI – Turkey Vulture

Bug o’the Week
by Kate Redmond

Bug o’the Week And Now for Something a Little Different XVI – Turkey Vulture

Howdy BugFans,

The BugLady hangs out on a tower by Lake Michigan from the beginning of September until the end of November, logging migrating raptors as they navigate south along the shoreline (up until this week, she was still seeing a few Monarchs and Common Green Darners, too).  She already misses the comforting presence of Turkey Vultures – 99.9% of this fall’s migrating Vultures have made their way past the hawk tower – she loves looking way out over the fields and seeing them rocking back and forth over the woods, taking care of business.

She wrote this biography for the newsletter of the Lake Michigan Bird Observatory (the organization formerly known as the Western Great Lakes Bird and Bat Observatory), an organization that would appreciate your support.

A sit on the hawk tower in mid-October of 2021 turned out to be a religious experience. Though they are not technically birds of prey, we do include migrating Turkey Vultures (TVs) in our Hawk Count, and of the 789 raptors of 10 species that passed by the tower on that amazing day, almost half were TVs! The vultures approached in groups of 15 to 30 birds, circling on warm updrafts as they moved south. As one group passed, two or three more could be seen approaching us from the north.  

Turkey Vultures get their name from dark plumage and bald, red heads that are reminiscent of Wild Turkeys. They’re also called buzzards. “Vulture” probably comes from the Latin “vellere,” which means “to pluck or tear,” and their scientific name, Cathartes aura, means “golden purifier or cleanser” (being eaten by a vulture after death was believed in some cultures to cleanse and release one’s soul). The Cherokees referred to TVs as “Peace Eagles” because although they look like eagles, Turkey Vultures don’t kill their food.    

Turkey Vultures are one of six species in the New World Vulture family Cathartidae, and they are not related to the vultures of Europe and Asia. Three of those New World species — the TV, Black Vulture, and California Condor — are found in the US. Turkey Vultures are the most widespread of our vultures, found from southern Canada into South America, and data suggest that their range is spreading to the north.

They’re generally found in open or semi-open country rather than in heavily wooded areas, and they are tolerant of human activity and of landscapes altered by man. Construction of Wisconsin’s interstate highway system began in the late 1940’s, and one source pointed to the subsequent increase in road kills as a cause of higher numbers of TVs here in the second half of the 20th century.   

These are big birds, with bodies about 30” long and wingspans of six feet. They are about three-quarters the size of a Bald Eagle, but at a maximum of four pounds, they are less than half an eagle’s weight, and they lack the strong, gripping talons of eagles and hawks. Most of their feathers are dark brownish gray, and in flight, the leading edge of their wing is dark and the trailing edge is silvery. Males and females look the same, and young TVs have gray heads. They do lots of soaring and not much flapping, their wings held in a wide “V” called a dihedral for stability, and they often tip back and forth.  

Turkey Vultures don’t have a voice box (syrinx), so their vocalizations are mainly grunts https://www.audubon.org/field-guide/bird/turkey-vulture and hisses https://www.allaboutbirds.org/guide/Turkey_Vulture/sounds that are used to startle intruders. 

Although they bathe frequently, people who get close to them will testify that vultures stink — partly because of their diet, and partly because when they’re hot, they excrete urine on their legs, which cools them as it evaporates and also disinfects their legs (it’s called “urohydrosis“).  

TVs are scavengers (“recyclers”) that mostly feed on dead mammals, though they will eat other dead vertebrates, and they are thought to eat more than 100 pounds of meat a year. They also feed on vegetation. They use their keen eyesight to locate carcasses, but vultures are also one of the few birds that have a good sense of smell, and they count on both senses as they fly low over roads and fields (and dumps and dumpsters) — they can sift out the odor of decay from a mile away. Like owls, they spit up pellets of indigestible bones and fur. TVs rarely take live prey, but Black Vultures do kill some newborn livestock and the occasional small pet.  

The amazing thing about Turkey Vultures’ food habits is that no matter how old the carcass or how riddled it is with bacteria, botulism, cholera, or other such organisms, their immune systems protect them from getting sick. Even more amazing is the fact that pathogens that are neutralized by the vultures’ highly acidic digestive juices (the pH is less than 1) are not present in their droppings! And, according to an article on the National Audubon Society website, “immensely powerful acids in the vultures’ gut begin digesting the flesh so thoroughly that they even destroy the prey’s DNA.” In addition, while they destroy some microbes, the birds apparently filter out some of the ingested bacteria and put it to work in their guts. The end result is that vultures reduce the amount of highly toxic pathogens in the environment, so, the cultural idea of being cleansed by being eaten by a Turkey Vulture has some biological truth.

During courtship, a group of TVs gather on the ground and hop around in a circle in a stylized dance with their wings spread (something this writer would dearly like to see!). They also perform “follow flights” in which one bird leads the other through elaborate aerial maneuvers. Pairs stay together for a long time, both on their breeding and their wintering grounds. 

Turkey Vultures lay one to three eggs in a slight depression that they scrape into the ground under bushes, in caves, hollow logs, and old buildings. They will use abandoned hawk nests, and they’ll reuse successful nest sites. Incubation lasts about five weeks, and after they hatch, the chicks are fed regurgitated food by both parents. They can fly at nine or ten weeks and are soon independent.

While their populations seem to be stable, Turkey Vultures are susceptible to collisions with power lines and other structures, with fences, and with cars as they gather at road kills. Poisoned baits, lead shot ingested from dead animals, and deliberate shootings are also mortality factors. They are protected by the Migratory Bird Treaty Act. 

Fun Facts about Turkey Vultures:

  • Through the years, the New World vultures have been classified with the falcons, with the storks and herons, and in their own order, but the latest DNA-sequencing seems to put them, for now, with the non-falcon birds of prey. 
  • When predators approach, TVs, young and old alike, defend themselves by projectile vomiting, sending a stream of caustic, semi-digested rotten meat as far as 10 feet away.
  • They may perch with wings outspread to warm up in the morning, to cool off during a hot day, or to dry wet feathers.
  • TVs like company –- they roost, soar, and migrate with other TVs. 
  • They are smart and curious, and in captivity will play games with their caretakers (in Wisconsin, you must be licensed to take a wild animal from the wild).

The BugLady is looking forward to their return in spring.

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Bug o’the Week – Monochromatic Stink Bug-Hunting Wasp

Bug o’the Week
by Kate Redmond

Bug o’the Week Monochromatic Stink Bug-Hunting Wasp

Howdy, BugFans,

Another wasp with a dynamite name!

When the BugLady found this wasp, she was struck by its curious appearance – fly-like eyes, waspy antennae, “broad-shouldered,” but with a very short abdomen (“It’s compact,” says bugguide.net).

It’s in the family Crabronidae, the Sand wasps and Square-headed wasps, which have been featured before, most recently in the form of the Robust katydid-hunting wasp.  Crabronidae is a large family that used to be lumped with the solitary wasps in the family Sphecidae, the mud daubers, sand wasps, and hunting wasps.  There are lots of Crabronid species worldwide; they create egg chambers and cache paralyzed invertebrates in them for their eventual larvae to eat, and many species are very fussy about the kinds of prey they collect.  Adults feed on nectar.

Monochromatic Stink Bug-Hunting Wasps (Astata unicolor) (probably) live in grasslands and savannas (members of the genus Astata can be hard to differentiate, but the MSBHW is a widespread species in the East).  Astata comes from the Greek word astatos, meaning “restless.”  According to the Minnesota Seasons website, it’s found “across southern Canada, throughout the United States and Mexico, and in Central America” but is not common anywhere.  Habitat/soil types probably help determine a species presence.  

These are very alert, curious, and fast-flying little (half-inch) wasps, with dark-tipped wings and a coating of silvery hairs.  The males’ wrap-around (holoptic) eyes are typical of the genus.  Here’s a Glamour Shot – https://bugguide.net/node/view/467930/bgimage

A female MSBHW’s prey of choice are the mature nymphs and adults of a few genera of stink bugs, including the Spined stink bug https://bugguide.net/node/view/875677.  Out West, their menu also includes the Western box elder bug.  

Males sit on perches to scout for females (those big eyes come in handy) – males emerge as adults about two weeks before females do, and they set up territories while they’re waiting (cherchez la femme).  They advertise by making brief, circular forays from perches. 

Females dig tunnels as deep as 14” in loose soil.  Heather Holm, in her epic book Wasps, Their Biology, Diversity, and Role as Beneficial Insects and Pollinators of Native Plants, writes that “after mating, the female begins excavating her nest in the ground, often preferring a partially concealed site with bare soil such as under a plant leaf.  As she excavates the nest, she loosens soil with her mandibles and forelegs, then pushes the soil up the burrow with the end of her abdomen.”  The tunnel contains several cells.

Holm continues, “She leaves the nest entrance open while searching for prey but while in the nest at night to rest, she closes the entrance with soil.  She searches for predatory stink bug nymphs in vegetation and likely uses olfactory senses in addition to sight to find her prey.  After capturing and stinging her prey https://bugguide.net/node/view/70575/bgimage, she grasps the prey by the antennae, then clutches it with her legs beneath her as she flies close to the ground back to her nest.  She either enters the nest clutching her prey or she places it on the ground next to the entrance.  If the latter, she enters the nest, emerges headfirst, then drags the prey down the burrow, clasping it with her mandibles.

Each cell is provisioned with approximately two to four stink bugs.  She temporarily stores the stink bugs at the bottom of the burrow until enough are collected to fully provision the cell.  She lays one egg on the first bug cached in the cell.

Ground-nesting wasps and bees have elaborate behaviors that help them relocate their nests.  Holm says, “When she is ready to leave the nest, her orientation first begins on the ground as she walks, making several passes over the nest before taking flight.  Then, she flies in circling arcs over the nest.  When she returns to the nesting area, she lands on the ground with her prey, then walks around for a while, repeating a similar on-the-ground orientation to the one performed before departing the nest.”  

This unobtrusive wasp is attracting some attention these days because it has discovered the invasive Brown marmorated stink bug (BMSB).  In a study in Oregon, 64% of the observed prey taken by the MSBHW were BMSBs, and a few other stink bugs it eats are considered crop pests.  Of course, solitary wasps are, well, solitary; you can’t just set up a hive and sic them on unwanted species, so they does their biological control on a small scale. 

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Bug o’the Week – Drumming Katydid

Bug o’the Week
by Kate Redmond

Bug o’the Week Drumming Katydid

Howdy, BugFans,

Sometimes you go looking for insects, and sometimes the insects find you.  The BugLady came back to her car from the Post Office one sunny afternoon in August and discovered this stunning katydid sitting above the driver’s door of her car.  Keeping one eye on traffic, she managed to get a few shots of it before moving it to a nearby hydrangea.

She had never heard of the Drumming katydids before.  They’re in the katydid family Tettigoniidae and in the subfamily Meconematinae, the Quiet-calling Katydids, which has about 200 species worldwide.  Three of the members of the subfamily make sounds that we can’t hear without the aid of an ultrasonic detector, and both of the species that occur in North America have been introduced.

Other names for the Drumming katydid (Meconema thalassinum) are the Oak Bush-Cricket (in Britain), Méconème Tambourinaire (not in Britain), Eichenschrecke (Oak locust) in Germany, Quiet-calling katydid, and Sea-Green Katydid (“thalassinum” means “sea green.”

This European katydid was first recorded in America in 1957 in western Long Island.  By 2004 it had made its way to Michigan, and now it inhabits much of the northeast quadrant of North America plus the Pacific Northwest.  It’s found in deciduous trees and in the vegetation below them; neither cars nor hydrangeas are listed as potential habitats, but the BugLady found a few other shots of Drumming katydids sitting on cars, and sources note that they are comfortable on and around man-made structures. 

Lots of members of the grasshopper/katydid bunch are known to spice up their vegetarian existence with a little protein by nibbling on dead insects or insect eggs.  Some sources say that Drumming katydids do exactly that, but others say that they are exclusively carnivorous, feeding on aphids and small larvae.  They aren’t considered plant pests in either the Old Country or the New.

What eats them?  The usual suspects, plus they are among the grasshopper/katydid species that Grass-carrying wasps (Isodontia) collect to provision their egg chambers.  Drumming katydids are also susceptible to a parasitic worm that takes over their nervous system and tells the katydid to head for any nearby body of water so that the worm can emerge there. 

Drumming katydids aren’t huge – maybe 4/5 of an inch long (plus the ovipositor, though the one she saw seemed bigger to the BugLady).  They have a hearing organ (tympanum) on each of their front legs (if you’re going to sing, you should have “ears” to hear it).  They have yellow feet https://bugguide.net/node/view/704348/bgimage, and because they’re katydids, they have extra-long antennae – pale orange, in their case.  Females have a long, curved ovipositor and males have long, slender, curved, hollow claspers (cerci) https://bugguide.net/node/view/205071/bgimage.  They are nocturnal.

Though males do have tiny teeth on their forewings (scientists aren’t sure why, unless it’s to add an ultrasonic stridulation/friction component to the katydid’s acoustic repertoire), they don’t have rough spots (stridulatory areas) at the base of their forewings, so they don’t use the usual katydid “file and scraper” modus operandi to attract a female.  Instead, they tap/drum a quick Morse code on a leaf with their hind tarsus – the tarsus is basically a five-segmented foot, and males have a hard pad on the first tarsal segment that females don’t.  Though the pattern of his song stays the same, the higher the temperature is, the more frequently he taps.  The soft sound may be heard by a human (one with better hearing than the BugLady’s) as far as 12 feet away, and it’s believed that the vibrations also travel through the substrate, but the BugLady couldn’t discover exactly how the female detects his signals.  

There’s only one generation per year – they overwinter as eggs that hatch in late spring and are mature by mid-August, and adults may be seen well into late fall.  Drumming katydids are small, and they lay their eggs in bark crevices, and it’s suspected that they made their way to America on imported plant material. 

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Bug o’the Week -German Yellowjacket Redux

Bug o’the Week
by Kate Redmond

Bug o’the Week German Yellowjacket Redux

Salutations, BugFans,

The BugLady has been busy, so she’s rerunning this episode from 2009.  There are still yellowjackets on the flowers.  The photographs in the original episode were (nasty) scanned color slides, and when the BugLady searched her files, she found pictures of three other yellowjacket species, but none of the German yellowjacket.  The folks at bugguide.net have some great shots:

of the face https://bugguide.net/node/view/1159222/bgimage,

the profile https://bugguide.net/node/view/320998/bgimage,

the back https://bugguide.net/node/view/1303274/bgimage,

and in flight – https://bugguide.net/node/view/856499/bgimage.

German Yellowjackets (GYJs), family Vespidae, are European wasps that arrived in the northeastern US in the early 1970’s and in Wisconsin a few years later.  These world travelers are now found on four continents and several oceanic islands.  Although the whole bee/wasp/hornet group is often labeled casually as “bees” (and GYJs have earned the nickname “garbage bee”), it’s easy to tell a honeybee from a wasp.  Honeybees are hairy, black and tan insects about ½” long; the similarly-sized, GYJs are less hairy and are clearly marked by nature’s warning colors, yellow and black.  Both species may nest in walls, but honeybees, which use their hives for years, do not nest underground. 

The nest is started in spring by a queen who has spent the winter sheltered in a crevice, leaf pile, or building.  She chews plant material, mixes this cellulose with saliva, forms it into a nest and nursery, and starts laying eggs https://bugguide.net/node/view/1899314/bgimage.  When the first workers emerge, they enlarge the nest https://bugguide.net/node/view/38722/bgimage, care for the larvae and queen, and forage for food.  Adults eat insects (live or dead), rotting fruit https://bugguide.net/node/view/1284571/bgimage, nectar and other sweet liquids (including sugar water in hummingbird feeders https://bugguide.net/node/view/1279647/bgimage), and workers bring pre-chewed protein to the larvae.   

Their nests often seem plastered/sprayed onto a surface; these are not the classic hanging, football-shaped nests of the larger paper wasps.  The GYJ nest in the glass case in the picture was collected from the front porch of an old building near Mayville, WI; Sherri is holding a typical hanging nest of a Bald-faced hornet/Bald-faced aerial yellowjacket.  GYJs often nest underground https://bugguide.net/node/view/317549/bgimage (the BugLady’s parents had a sizable colony under the cement slabs of their front walk), but many nests are built in sheltered spots above ground or inside walls, and GYJs that nest in walls and attics may chew through your home’s inner walls into the house.  Thirty years ago, almost all yellowjackets caught in sweet traps in urban areas were Germans, while those snagged in rural areas were native.  But now, this urban, alien species is moving out into the sticks and displacing native species. 

Wasp populations peak in late summer, when a very large nest may contain 15,000 inhabitants.  A nest built in a protected spot can remain active into late fall, but the queen and workers will die before winter, leaving a new generation of fertile queens to restart the process.  In Wisconsin, nests are not used for a second year (an old nest containing dead workers and larvae makes a great food source for raccoons and skunks).  In subtropical climates like California, this adaptable, temperate-zone wasp is establishing colonies that last two or three years and grow to mind-boggling sizes (think pick-up truck size). 

Wasps’ plusses as pollinators and as predators on unwanted insects are canceled by their painful (and, to some people, dangerous) stings and by their inconvenient choices for nest sites.  Honeybees have barbed stingers and can only sting once – the act causes their death.  For that reason, they are less aggressive away from their hives.  Wasps can sting repeatedly, and they have a “hair trigger” temperament https://bugguide.net/node/view/507730/bgimage both near their nests and away from them. 

GYJs are the “gals” that have been making outdoor eating risky for the past 40 years.  Close encounters can be minimized by checking picnic foods and drinks before each bite or sip, avoiding bright clothing and flowery perfumes, keeping garbage cans clean and closed, removing bruised and fallen fruit from the ground in orchards, and refraining from jumping around waving one’s hands hysterically at the sight of a yellow and black flying object.  The BugLady knew one teacher who poured a small cup of beverage for the wasps when she took her students outside to snack.  The kids were instructed to tell the wasps calmly to go use their own cup.

Sugar-water traps will attract GYJs, but these are more effective in early spring when the queens are foraging.  In late summer and fall they barely dent the population.  Removal of a large nest, either above or below ground, is not a job for amateurs; you can empty entire cans of wasp spray into a nest opening with little effect (other than annoying its occupants) because there often are multiple entrances.  Call an exterminator.

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Bug o’the Week – Bugs at the End of Summer

Bug o’the Week
by Kate Redmond

Bug o’the Week Bugs at the End of Summer

Howdy, BugFans,

The Autumnal Equinox is fast upon us, alas, and even though it was a very hot one, the BugLady would like to push that Restart button and go back to the beginning of August.  Failing that, here are some of the bugs that crossed her trail in the second half of summer.

BARK LOUSE – Bark lice (order (Psocidae) are often seen in herds, both as adults and nymphs https://bugguide.net/node/view/1716157/bgimage.  This species, Cerastipsocus venosus, is known collectively as Tree cattle.  Bugguide.net says that they feed on “accumulations of fungi, algae, lichen, dead bark and other materials that occur on tree trunks and large limbs.”  And on the BugLady’s porch rails.  So, they clean up after the BugLady outside, and the silverfish take care of the inside of her cottage. 

YELLOW-HORNED FLOWER LONG-HORNED BEETLE – The YHFLHB (Strangalia luteicornis) is in the Longhorned beetle family Cerambycidae and the subfamily Lepturinae, the flower longhorns.  Flower longhorns are often found on flowers by day, feeding on the protein-rich pollen, and many (but not all) species are wedge-shaped – sometimes dramatically so.  Their larvae feed on dead and dying woody material, and certain fungi that they ingest as part of their meal then aids the grub’s ability to digest cellulose (in some species of flower longhorns, Mom inoculates the eggshell as she lays it with a yeast that becomes part of the grub’s intestinal microflora). 

AMBUSH BUG – What would summer be without the extraordinarily-well-camouflaged (and voracious) ambush bugs – one of the BugLady’s favorites? 

LEAF-FOOTED BUG – Late summer is True bug season (remember – only one insect order, the Hemiptera, can officially be called Bugs).  This particular bug is the almost-grown nymph of a leaf-footed bug called Acanthocephala terminalis (no common name).  Newly-hatched nymphs, with their spiny butts and improbable antennae, are pretty cute https://bugguide.net/node/view/933082/bgimage

SPIDER WEB AND PREY – All wrapped up and nowhere to go.   

BALD-FACED HORNET – The BugLady corresponded this summer with a man who was stung twice in his mouth by a Bald-faced hornet (now called Bald-faced aerial yellowjacket).  These are the gals that build the closed, football-shaped, paper nests that hang in trees, and while they are valiant/dangerous in defense of their homes, they don’t defend the flower tops where they feed.  The BugLady’s correspondent was apparently walking along blamelessly when his open mouth encountered a flying hornet.  Stings on the face, and especially in the mouth, can be dangerous because of swelling, even if you’re not allergic. 

An entomologist named Schmidt went around deliberately getting stung by the ants, hornets, bees, and wasps of the world and writing descriptions of his discomfort that are sometimes reminiscent of a wine-tasting.  He rated the Bald-faced hornet at a 2 out of 4 on his pain scale – “rich, hearty, slightly crunchy.  Similar to getting your hand mashed in a revolving door” https://reliantpest.com/north-american-schmidt-sting-index/.  Not surprisingly, lots of exterminator companies have posted the scale because they want to sell us something.   

COMMON WOOD NYMPH – A medium/large Satyr butterfly of sunny fields, Common Wood Nymphs are not often seen nectaring on flowers, preferring fungi and rotting fruit.  They lay their eggs on grasses in late summer, but when the caterpillars hatch, they go into hibernation immediately, without feeding, to continue their development the following spring. 

CANDY-STRIPED LEAFHOPPER – what glorious things sometimes come in ¼” packages!  And, they have superpowers!  Leafhoppers suck plant juices.  Most plant sap has a sugar concentration of only a few percent, so leafhoppers have to consume a lot of it to get enough calories, and they excrete the excess (honeydew) “under pressure” with a tiny, but sometimes-audible, “pop.”  Because of this, they’re called “sharpshooters.”  And – they vocalize, but too softly for us to hear.

BROWN WASP MANTIDFLY – Yes, those poised, mantis-like front legs are used to grab smaller insects (mantidflies also sip nectar); and yes, this mantidfly does look like a paper wasp at first glance (but – no stinger).  Scroll down to see how this very flexible species has evolved to imitate different species of wasps in different parts of the country (the mantidfly is on the left) https://bugguide.net/node/view/4825

Their stalked eggs are attached to leaves https://bugguide.net/node/view/216544/bgimage, and when the eggs hatch, each larva waits for a passing spider, hitches a ride (feeding on the spider like a tick), and eventually infiltrates the spider’s egg sac, where it spends the rest of its larval life eating spider eggs.

WHITE-FACED MEADOWHAWK – You rarely see this species in tandem flights out over the water or ovipositing into shallow water.  They often “speculate” – bobbing up and down in damp areas by a pond’s edge, with the female lobbing her eggs onto the ground.  The plan is that spring rains will wash the eggs into the water. 

RED-SPOTTED PURPLE – What a classy butterfly!  Three Fun Facts about Red-spotted Purples: 1) the red is on the underside of the wings https://bugguide.net/node/view/557370; 2) though they are “tailless,” they are mimicking Pipe-vine Swallowtails, which are poisonous https://bugguide.net/node/view/2264557/bgimage; and 3) partly-grown caterpillars spend the winter inside a leaf that they’ve rolled into a tube and fastened to a twig, and they emerge and resume eating the following year (scroll down for a picture of a hibernaculum and for a bonus lesson about “frass spars” https://entnemdept.ufl.edu/creatures/bfly/red-spotted_purple.htm).  Within their leafy tube, they drop about 1/3 of the water weight in their body in order to avoid cell damage from freezing.

CRAB SPIDER – Nothing to see here, folks, just move along.

GREEN STINK BUG – Another common sight in late summer, along with their flashy, almost-grown nymphs https://bugguide.net/node/view/885566.  Some stink bugs are carnivores, and some are herbivores, and some of the herbivores are considered crop pests.  They aren’t chewers, they suck plant juices with mouths like drinking straws, which can deform fruits and seeds, damage twigs, and wither leaves.  Green Stink bugs (Pentatoma hilaris) (hilaris means “lively or cheerful”) feed on a large variety of plants (they’re “polyphagous”).  Newly-hatched green stinkbugs aren’t green https://bugguide.net/node/view/127137/bgimage.

TIGER SWALLOWTAIL CATERPILLAR – No – those aren’t eyes.  They’re pigment spots that are designed to fool you into thinking it’s a snake.  Young Tiger Swallowtail caterpillars start out as bird poop mimics https://bugguide.net/node/view/1883543/bgimage, but midway through their development, they go into snake mode, completing the effect by everting, when they feel threatened, a two-pronged, soft, orange, odorous projection (the osmeterium) that looks like a snake’s forked tongue https://bugguide.net/node/view/2214191/bgimage.  Tiger Swallowtails have two generations per year.  Caterpillars of the butterflies we see in June don’t spend long in the chrysalis, emerging in mid-August and getting to work on the next generation.  This caterpillar will overwinter as a chrysalis.  Don’t tell the other insects, but Tiger Swallowtails are the BugLady’s favorites.

As she visited her usual haunts this summer, the BugLady was dismayed at the lack of insects.  Sure, the goldenrods are full of flies, bees and wasps of various stripes, and the grasshoppers and tree crickets are singing their September songs.  But she saw six Tiger Swallowtails this summer.  Total.  And maybe a dozen meadowhawks.  During one mid-summer Dragonfly count years ago, the BugLady simply stopped counting meadowhawks when she got to 250 because it was distracting her from the other species.  Common Wood Nymphs used to emerge in early July by the score to filter through the grasses.  Even crab spiders and ambush bugs seemed scarce this year. 

What good are insects?  Sometimes it’s hard to drum up sympathy for a group that many people routinely swat, stomp, spray, or zap.  But insects provide food for birds and for other insects; they’re pollinators, and they provide other ecosystem services including pest control and garbage pick-up. 

(And, of course, they’re awesome.)

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Bug o’the Week – Golden green sweat bee

Bug o’the Week
by Kate Redmond

Bug o’the Week Golden green sweat bee

Howdy, BugFans,

Wisconsin is home to between 500 and 600 species of wild bees, ranging in size from today’s sweat bee to bumble bees many times larger (there are about 4,000 bee species in the US).  If a small brown or green bee landed on your arm and started sipping salt while you were working/sweating outside in the summer, you’ve met a sweat bee.  Typically, no one is harmed in these encounters unless you brush the bee away roughly.

The BugLady’s husband was allergic to sweat bees, but when he went to the allergist to see if desensitization shots were available, the doctor said “What’s a sweat bee?”  Which didn’t bode well for any shots.

Sweat bees can be a bear to differentiate (as one site warned, “Many species won’t be identifiable from photos”), and a microscope is needed to tell some species apart.  Still, this is a seriously tiny sweat bee with an unusual color. So, the BugLady finds herself back out on that taxonomic limb again, but she’s gotten comfortable out there over the years, and she’s calling this one a Golden green sweat bee.

Golden green sweat bees (Augochlorella aurata) are one of about 100 species in Wisconsin in the family Halictidae, the Sweat, Furrow, Nomiine, and Short-faced Bees.  Augochlor is a Greek prefix meaning “intensified gold-green,” and “aurata” means “gilded” or “golden.”  Despite their name, most Golden green sweat bees are quite green https://bugguide.net/node/view/1894237/bgimage, but some are pinkish https://bugguide.net/node/view/1272175/bgimage, some are reddish https://bugguide.net/node/view/1124880/bgimage, some are blue https://bugguide.net/node/view/1180911/bgimage, and some are bi-colored https://bugguide.net/node/view/825764/bgimage.  They are about one-fifth of an inch long, with females slightly longer than males. 

Here are some Extreme Macros – https://www.usgs.gov/media/images/augochlorella-aurata-f-face-md-boonsboro (also available on eBay as a headshot), https://www.usgs.gov/media/images/augochlorella-aurata-f-back-md-boonesboro, and https://www.fws.gov/media/golden-green-sweat-bee-augochlorella-aurata.  

They have a patchy northern range mostly east of the Rockies, and of the seven Augochlorella species in North America, Golden green sweat bees are found the farthest north.  They are common in fields in eastern North America, where they are generalist pollinators that forage on flowers in a bunch of different plant families.  Along with wildflowers, they also pollinate agricultural crops like apples, strawberries, alfalfa, tomatoes, and sunflowers.  They carry pollen in hairs on their back legs https://bugguide.net/node/view/1306100/bgimage.  

The vast majority of bees, including many of the Halicitdae and some of the Augochlorella, are solitary rather than communal bees – single Moms who create and provision egg chambers without the help of workers.  Golden green sweat bees are flexible about the idea – at higher latitudes and altitudes (areas that have shorter growing seasons), they tend to be more solitary, but when they’re in warmer climes, they are called “primitively eusocial.”  Eusocial describes the most advanced social behavior – think ant hill – characterized by cooperative brood care, overlapping generations within a colony, division of labor (castes), and reproductive and non-reproductive individuals.  

In favorable climates, the fertile female overwinters and starts the colony in spring, excavating a nest tunnel (here are some diagrams of A. aurata nest tunnels https://actbeekeepers.asn.au/bee-buzz-box-july-2023-the-catacomb-part-iva-the-facultative-eusocia/figure-6-nesting-behaviour-of-facultatively-eusocial-augochlorella-aurata-1/), collecting pollen and fashioning it into pollen balls for her young, and laying six to eight eggs that will produce both males and females.  Newly hatched males leave the nest, but newly-hatched females become workers that care for the queen.  Later in the season, she produces another small batch of males and females that will fly out and mate in fall.  A fertile female will dig down into the lowest/warmest part of the nest and hunker down until May, and the beat goes on.  

Nest are dug in bare ground in woods and fields and can be as deep as 10 inches.  The Vermont Center for Ecostudies Vermont Atlas of Life site included a picture of a nest entrance with a turret around the opening, but the BugLady didn’t find any other references to that behavior https://val.vtecostudies.org/wp-content/uploads/2021/05/A.-auratta-nest-SPH.jpeg

Neat picture of a Golden green sweat bee with a raindrop https://bugguide.net/node/view/33594/bgimage.  About the picture, entomologist Eric Eaton wrote. “It might be that the rain dissolved honeydew that had accumulated on the leaf.”

Here’s a great source of information about bees, though not all NY bees appear here in Wisconsin, and vice versa https://www.sharpeatmanguides.com/wild-bee-id-guide-new-york.  Check the Wild Bee ID guide tab. 

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Bug o’the Week – Euderces picipes Beetle

Bug o’the Week
by Kate Redmond

Bug o’the Week Euderces picipes Beetle

Greetings, BugFans,

When the BugLady saw these two tiny (5mm/¼”), black insects on a flower, her first thought was “ants,” followed immediately by a mental head slap.  They were piggyback – worker ants don’t do that, and royal ants have wings, and males are way smaller than females.  A (much) closer look revealed two long-horned beetles, Family Cerambycidae.

The Cerambycids (aka the longicorns, borers, girdlers, sawyers, or timber beetles) are a large group of beetles (1,000 species in North America; 30,000 worldwide).  Some are spectacular https://bugguide.net/node/view/1767144/bgimagehttps://bugguide.net/node/view/2247879/bgimagehttps://bugguide.net/node/view/226098/bgimage,; some are humble – https://bugguide.net/node/view/119390/bgpagehttps://bugguide.net/node/view/1285181/bgpage,; some are just odd – https://bugguide.net/node/view/1472921/bgimagehttps://bugguide.net/node/view/2198732/bgimagehttps://bugguide.net/node/view/1569423/bgimage; and at least one species graces a Wanted Poster – the large, non-native Asian Longhorned beetle that’s been threatening our hardwoods since 1996 https://bugguide.net/node/view/631192/bgimage.  A number of native species are also persona non grata, especially with the lumber industry. 

Many (but not all) Cerambycids have long antennae (“horns”) – some spectacularly long https://bugguide.net/node/view/2119609/bgimage.  

Cerambycid larvae are often called round headed borers, and it’s the “borer” part that gets them in trouble.  They feed on the tissue within the stems, trunks, and roots of plants (woody and herbaceous).  Depending on the species, they may (or may not) wait for a tree to be compromised and bore into dead or dying wood – they are part of the recycling process.  They may be found in untreated lumber which, if it’s part of your house, you may not be ready to recycle yet.  Female Cerambycids locate the correct host species for their offspring by analyzing the chemical signatures of plants, and some damage trees by girdling twigs while they’re ovipositing.  Adults variously eat sap, nectar, pollen, fruit, fungi, foliage, and bark, or nothing at all.

The star of today’s show represents a tiny drop in the great Cerambycid bucket – there are only four species in the genus Euderces in North America (60 total), and bugguide.net calls them “among the smallest of our longhorns.” 

EUDERCES PICIPES (no common name) is found in the first half of summer, east of the Great Plains.  Its larvae feed under the bark of hickory, black walnut, oak, elm, dogwood, and locust branches.  According to the excellent Illinois Wildflowers website, adults are found on flowers in the aster, sumac (cashew), carrot, holly, honeysuckle, mint, rose, greenbriar, and buckthorn families, and many of the bugguide.net pictures show them on white flowers.

Along with the black morph beetles that the BugLady saw, Euderces picipes also comes in red https://bugguide.net/node/view/2047840/bgimage.  The black morph is more common in the northern part of its range, and the red is more common in the south.  Both colors are found in transition zones, and mixed pairs can be seen piggyback.  Apparently, they know who they are. 

Many of the species in the genus Euderces and in their tribe, Tillomorphini, are ant mimics, but ant mimicry (myrmecophily, pronounced myr’ me coph’ i ly) is not limited to beetles – spiders do it https://en.wikipedia.org/wiki/Ant_mimicry#/media/File:Ant_and_jumping_spider_Gorongosa_National_Park,_Mozambique.jpg and crickets https://en.wikipedia.org/wiki/Ant_mimicry#/media/File:Macroxiphus_sp_cricket.jpg, and so do other arthropods.  There are even ants that mimic other ants, though scientists aren’t sure why.

There are several reasons why it might be beneficial to look like an ant.  One reason is to eat, and another is to avoid being eaten.  Besides its morphology (size, shape, structure), an insect or spider that wants to insert itself among the ants in order to eat them (aggressive mimicry) must also act and smell like an ant (or, at least, not like a spider).  An ant mimic that wants to avoid being eaten (protective mimicry) is taking advantage of ants’ reputation for protecting themselves by biting, stinging, formic acid, or all of the above, as well as for having an anthill full of sister ants that are always on call in an emergency (all of which the BugLady learned at an early age).  Not many organisms mess with ants.  

Especially not the BugLady.

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

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