Bug o’the Week – Tall Flea Beetle

Bug o’the Week

Tall Flea Beetle

Howdy, BugFans,

Sometimes, the BugLady gets a surprise as she’s researching an insect, and that was the case this week.

She saw a cluster of these pretty beetles when she was on a boardwalk in a wetland.  Their pedigree?  They are leaf beetles in the huge family Chrysomelidae; within that family, they’re in the tribe Alticini – the flea beetles, and they are (probably) Disonycha procera (Disonycha means “double-clawed”).  There are 470 members of that tribe in North America, and more elsewhere.  The BugLady has photographed one other, equally pretty flea beetle species when it was feeding on her pussy willows https://bugguide.net/node/view/2175205/bgimage.

Disonycha procera is very similar to Disonycha pensylvanica (not a typo, simply an old misspelling that is now embedded in the taxonomy of a few species), and in fact, it is in the “Disonycha pensylvanica species group,” about which bugguide.net says “The three species of the D. pensylvanica- group are not always safely identified – last hope is male genitalia, in some cases.”  So the BugLady has repaired to her well-worn seat, far out on that taxonomic limb, and is calling it Disonycha procera.  Only one source gave it a common name, but there was no explanation why this small insect might be called the Tall flea beetle.   

Tall flea beetles are found east of the Rockies, but not solidly, and into Central America, wherever their food plants grow.  Because some of their food plants grow on the edges of wetlands, Tall flea beetles are listed as semi-aquatic beetles by a few sources. 

The BugLady couldn’t find much about their life history.  Bugguide.net says that you can find both adult and larval Tall flea beetles feeding together on host plants, and a write-up about another genus member said that it overwinters as an adult, wakes up in spring, and lays eggs on or near the host plant, and the BugLady assumes that the Tall flea beetle does the same. 

Many Chrysomelids are attached to and named for their specific food plants, and for some flea beetles, those plants are agricultural crops like spinach (the Spinach flea beetle), beets, eggplant (the Eggplant flea beetle), and cruciferous plants like broccoli, cauliflower, cabbage, kale, (the Crucifer flea beetle).  But some Disonycha beetles eat invasive plants like Leafy spurge and are considered beneficial.  Adults chew holes in various parts of the plants – stems, leaves and petals (they like to feed in sunny weather) – and larvae may feed on the undersides of the leaves or on roots.  Tall flea beetles feed on plants in the genus Polygonum – knotweed, smartweed, bindweed, and tear-thumb (and it would be nice if a whole bunch of them would gang up on the very invasive Japanese Knotweed).   

Some Flea beetles shelter in the soil during bad weather and emerge when the rain quits and the sun is out again.  In Germany, this has earned them the name Erdflöhe (earth flea).  

So, here’s the funny thing about the Tall flea beetle.  Flea beetles (tribe Alticini) are so named because they jump around (like fleas) when they’re disturbed.  The BugLady certainly didn’t see any jumping – they were about as staid a bunch of beetles as you could hope to find – and she couldn’t find a video of it.  In this jumping they are aided by disproportionately large hind legs https://bugguide.net/node/view/915939/bgimage (all the better to jump with, my dear), though they get around routinely by walking and flying.  There are jumpers in a few other groups of beetles, too, like the weevils, Buprestids (jewel beetles), and marsh beetles.

Flea beetles jump using particular tendons that act like springs when initiated by the tensing and release of the leg’s extensor muscles.  Quoting two other researchers’ work in their paper, Nadein and Betz said that “They suggested that the high take-off acceleration, high velocity and short take-off time are compatible with jumping based on a spring-driven mechanism”.  Another group of researchers likened the movement to a catapult, and they based their design for a bionic jumping leg on the beetles’ anatomy (don’t ask the BugLady to explain anything more about this, but she can share links to a few articles).  

Mother Nature creates; man imitates.  

Monarch butterflies are nearing their destinations https://maps.journeynorth.org/map/?year=2022&map=monarch-adult-fall.  The BugLady will be interested in the numbers on the wintering grounds this year – Monarchs were scarce here this summer.

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

Bugs at the End of Summer

Howdy, BugFans,

The general rule of thumb is that if you want to find insects, look at flowers.  Even though summer is fading, there are still flowers in bloom.  Some Liatris/blazing stars linger, along with brown-eyed Susan, wild sunflowers, asters and goldenrod (more than a century ago, Asa Gray said that the 12 pages about goldenrods in his Manual of the Botany of the Northern United States, from New England to Wisconsin and South to Ohio and Pennsylvania Inclusive (aka Gray’s Manual) were the most uninteresting in the Manual).  Late summer and early fall are dominated by flies, bees and wasps, and by grasshoppers, katydids, and crickets.

Most adult insects die by the first frosts, leaving behind the next generation in the form of eggs or pupae (occasionally as nymphs or larvae), so the clock is starting to tick pretty loudly.  As BugFan Mary stated dispassionately many years ago, they’re dead and they don’t know it yet.  Meanwhile, their activities are centered on eating and on producing the next generation.

AMBUSH BUG (pictured above) – One of the BugLady’s favorite insects is the ambush bug (she’s always had a soft spot in her heart for predators).  Ambush bugs tuck themselves down into the middle of a flower and wait for pollinators.  They grasp their prey with their strong front legs, inject a meat tenderizer, and slurp out the softened innards.  They’re paired up these days (the BugLady has a picture of a stack of three), and she has several pictures where the female is multitasking – eating an insect while mating.

BUMBLE BEE – A bumble bee forages for nectar and pollen for the brood well into September, but the brood will not survive the winter.  Only the newly-fertilized queens will see the spring and establish a new colony.  Moral of the story – plant Liatris/Blazing star.

PUNCTURED TIGER BEETLES (aka Sidewalk or Backroad Tiger Beetles) are named for the rows of pits on their very-slightly-iridescent elytra (hard wing coverings).  They’re common across the continent in dry, sandy, bare spots, and as one of their names suggests, they’re sometimes seen on sidewalks.  Like their (much) larger namesakes, Tiger beetles chase their prey https://bugguide.net/node/view/1106590/bgimage.  For more info http://www.naturenorth.com/Tiger%20Beetle/The%20Tiger%20Beetles%20of%20Manitoba.pdf.  

Some Punctured tiger beetles are “plain” https://bugguide.net/node/view/1343674/bgimage, and some are “fancy” https://bugguide.net/node/view/223895, and some are green https://bugguide.net/node/view/2025474/bgimage.  

FAMILIAR BLUETS signal the end of the damselfly season.  Big, robust, and startlingly-blue, they’re one of the BugLady’s favorite bluets.  

EASTERN COMMA – There are two generations/broods/”flights” of Commas (and Question Marks – the “anglewings”) each year.  The second generation overwinters as adults, tucked up into a sheltered spot (a hibernaculum).  They sometimes emerge during a January thaw, but they quickly resume their winter’s sleep.  They fly briefly in spring – one of our early butterflies – and produce the summer brood.

FALL FIELD CRICKET – Poking her ovipositor into the soil and planting the next generation.  Her eggs will hatch in spring, and her omnivorous offspring will eat leaves, fruits, grain, and other invertebrates. 

The BugLady loves their simple songs http://songsofinsects.com/crickets/spring-and-fall-field-crickets and is happy when a cricket finds its way indoors in fall.  Males form a resonating chamber by setting their wings at a certain angle; then they rub their wings together to produce sound (one wing has a scraper edge and the other has teeth).  There are mathematical formulae for calculating the ambient air temperature based on cricket chirps that give you the temperature in the microclimate on the ground where the cricket is chirping (add the number of chirps by a single field cricket in 15 seconds to 40). 

CANADA DARNER – Common Green Darners are robust dragonflies that fill the late summer skies with dramatic feeding and migratory swarms.  There are other darners, though, primarily the non-migratory mosaic darners (like the Canada, Green-striped, Lance-tipped, and Shadow Darners) whose abdomens have blue and black, “tile-like” patterns.  Identify them by the shape of the colored stripe on the thorax and by the shape of the male’s claspers (lest you think it’s too easy, females come in a number of color morphs – this is a green-form female Canada Darner).  

MONARCH BUTTERFLIES were alarmingly scarce this summer – the short-lived Gen 3 and Gen 4, whose job it is to build the population in the run-up up to the migratory Gen 5, simply weren’t there.  But, on one of the BugLady’s recent stints on the hawk tower, she saw 289 Monarchs heading south during a six-hour watch.  Moral – Plant goldenrod (and native milkweeds).

GOLDENROD CRAB SPIDER – Like ambush bugs, crab spiders live on a diet of pollinators.  They don’t build trap nets and wait for their prey to come to them, they pursue it.  Sometimes they lurk on the underside of the flower, but their camouflage makes hiding unnecessary.  This female looks like she’s sitting at the dinner table.

RED-LEGGED GRASSHOPPERS are very common in sunny grasslands at this time of year from coast to coast.  They eat lots of different kinds of plants (including some agricultural crops, which does not endear them to farmers), but they prefer plants in the Legume/pea family and the Composite/aster family.  As the air temperature increases – and when predators are around – they eat more carbs.  Grasshoppers are food for spiders, many birds, and other wildlife.  Moral of the story – plant wild sunflowers.

PAINTER LADY – You don’t get to be the most widespread butterfly in the world (found everywhere except Antarctica and South America) by being a picky eater.  It migrates north in spring – sometimes in large numbers and sometimes in small.

THIN-LEGGED WOLF SPIDER – This Thin-legged wolf spider formed an egg sac (with about 50 eggs inside), attached it to her spinnerets and is going about her business.  When the eggs hatch, her young will climb up on her abdomen and ride around piggyback for a few weeks before dismounting and going about their lives. 

GREAT BLACK WASP and GREAT GOLDEN DIGGER WASP – Two impressive (1 ¼” long) wasps grace the flower tops at the end of summer.  Both are good pollinators, both are solitary species that eat pollen and nectar, and both dig tunnels and provision chambers with paralyzed insects for their eventual offspring.  Great Black Wasps https://uwm.edu/field-station/great-black-wasp/ select crickets and grasshoppers for their young’s’ pantry, and so do Great Golden digger wasps https://uwm.edu/field-station/great-golden-digger-wasp-family-sphecidae/.  Neither is aggressive.  

The moral of the story?  Plant lemon horsemint.

Kate Redmond, The BugLady

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

Bug o’the Week – Black-margined Loosestrife Beetle

Bug o’the Week

Black-margined Loosestrife Beetle

Howdy, BugFans,

Purple loosestrife is a beautiful plant, with great wands of magenta flowers waving in the breeze.  Some say that, like a long list of other invasives, it entered the country in the ballast of ocean-going ships; others say that it was imported deliberately because it’s a medicinal plant as well as a great honeybee plant.  The BugLady knew a beekeeper who seeded purple loosestrife from the back of his snowmobile one winter, before he knew better (repent at leisure).  At any rate, it’s been here for 150 years or so, but it really started getting our attention in the 1970’s.  On its home turf, it exists in proportion to other wetland plants; here, it crowds out native vegetation, its dense stands discourage nesting waterfowl, and it’s not used by wildlife as a food plant (insects sure love the flowers, though). There are native loosestrifes, but they’re not invasive.

All those spectacular flowers produce masses of seeds (a single plant’s output can be in the millions of seeds, annually).  In gardens and upland situations, they fall to the ground and they grow or they don’t and that’s fine – the seeds stay pretty close to the parent plant.  In wetlands, the seeds fall into the water and float away to colonize other corners of the marsh or pond edge or ditch.  At the start of the battle against the purple loosestrife invasion in the 1980’s, Montezuma National Wildlife Refuge, at the north end of Cayuga Lake in NY, an area whose massive cattail marshes historically supported a thriving chair caning industry, had become wall-to-wall loosestrife.

It’s hard to get people psyched up about whacking beautiful plants.  It frustrated the BugLady’s husband that as some people were working to get purple loosestrife banned, nurseries continued to sell it (he also worked hard on our county fair officials to ban its use in their flower arranging competition).  Somewhere there exists a photo of our oldest at age 5, decked out in her Purple Loosestrife Task Force tee-shirt, dwarfed by the bundle of loosestrife that she’s holding.  You get the picture.  In some states, including Wisconsin, it’s now illegal to buy, sell, or plant it, but seeds are available online. 

This is a story of (very carefully vetted) biological control. 

When purple loosestrife began taking over American wetlands, scientists visited the Old Country to identify the grazers that the plant had left behind, and they found three species of weevils and two leaf beetles (family Chrysomelidae), Galerucella calmariensis and G. pusilla – the “Cella” beetles.  The BugLady thinks that she photographed the Black-margined Loosestrife Beetle (Galerucella calmariensis) (BMLB) (some are “bandier” than others https://bugguide.net/node/view/399423).   

The BMLB’s native range is the Palearctic realm – Europe, most of Asia, and North Africa.  It was introduced to this side of the Pond in 1992, after an impressive testing regime that involved inviting the beetle to sample some 50 species of North American plants to see if it would stray to another food plant.  The tests were done in Europe instead of risking an escape here. In the tests, the Cella beetles vastly preferred purple loosestrife (they were mildly interested in our native Winged loosestrife (Lythrum alatum) in the lab, but preferred purple loosestrife in the field).  Since then, the beetles have been introduced in southeastern Canada and 27 Northeastern, Northwestern, and Upper Midwestern states, and they’re doing a fine job, indeed.  The two Cella beetles and two of the European weevils have been in play in Wisconsin since 1994.

Both the larvae and the adult BMLBs feed on purple loosestrife – the larvae on buds, shoots, and leaves (where they skeletonize the lower surface) (at a high density, the larvae alone can defoliate a plant), and the adults on the leaves, where their feeding causes a distinct “shot hole” defoliation.  Their one-two punch diminishes seed production and impairs photosynthesis, so that the plant stores less starch in its roots, killing or making them less vigorous.  As loosestrife plants decline, native plants can move back in. 

The biographies of the two species of Cella beetles are very similar, except for a small difference in timing – one species leads off, and the other bats cleanup.  According to bugguide.net, “N. calmariensis emerges about a week before N. pusilla, first eating the leaves, shoots, and buds; then the N. pusilla eats the new growth, weakening the loosestrife, and after a few years the plants die off.”

Adults eat, meet, and mate https://bugguide.net/node/view/2004790/bgimage on purple loosestrife, and females lay 300 to 400 eggs in batches on its stem and leaves.  They are not shy about striking out and finding new patches of loosestrife plants to colonize.  The larvae feed and then drop down and pupate in the soil (or in the plant stem, if the water is high), emerging as adults before the frosts to feed again.  Adults overwinter in the leaf litter at the base of the plants, emerging as the loosestrife starts growing again. 

Biological control of purple loosestrife isn’t quite as easy as tossing a bunch of Cella beetles out into a marsh and watching the loosestrife fade away.  The beetles are very susceptible to pesticides; they’re not attracted to loosestrife that’s growing in the shade or in high water; and a couple of species of lady beetles, a ground beetle, and a stink bug consider BMLBs delicious, slowing them but not stopping their spread.  According to the Cornell University (Go, Big Red!) College of Agriculture and Life Sciences’ Biological Control website, it’s estimated that once established, the work of the weevils and leaf beetles will reduce the loosestrife populations by about 90% over about 90% of its present range.  But it’s a long game – it may take three to five years (one source says seven to ten) for the beetles to build up to levels where they can significantly impact purple loosestrife. 

And the long, long game?  According to Reinartz’s Law of Biomass Availability, eventually native species will recognize that this vast mess of plants is edible (simply put – “If You Grow It, They Will Come”).

Check with the Wisconsin DNR for information about rearing Cella beetles for release https://dnr.wisconsin.gov/topic/Invasives/loosestrife.html.

Kate Redmond, The BugLady

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

Bug o’the Week – Rose Chafer Beetle

Bug o’the Week

Black-margined Loosestrife Beetle

Howdy, BugFans,

Purple loosestrife is a beautiful plant, with great wands of magenta flowers waving in the breeze.  Some say that, like a long list of other invasives, it entered the country in the ballast of ocean-going ships; others say that it was imported deliberately because it’s a medicinal plant as well as a great honeybee plant.  The BugLady knew a beekeeper who seeded purple loosestrife from the back of his snowmobile one winter, before he knew better (repent at leisure).  At any rate, it’s been here for 150 years or so, but it really started getting our attention in the 1970’s.  On its home turf, it exists in proportion to other wetland plants; here, it crowds out native vegetation, its dense stands discourage nesting waterfowl, and it’s not used by wildlife as a food plant (insects sure love the flowers, though). There are native loosestrifes, but they’re not invasive.

Rose chafers can be found in grasslands, gardens, and viney edges over much of eastern North America as far west as Colorado and Montana, although distribution gets spotty the farther South you get. They especially like sandy areas (more about that in a sec).  Bugguide.net considers the western records to be “iffy” because of the possibility of confusing the Rose chafer with one of the other two species in the genus Macrodactylus that live north of Mexico (https://bugguide.net/node/view/939033/bgpage, and https://bugguide.net/node/view/1253988/bgimage), but insects can find an infinite number of ways to hitchhike.

They’re about a half-inch long (females are bulkier than males), covered with yellow hairs that rub off with age (or in the case of the female, with mating), exposing the dark cuticle beneath.  The official name for their antennae is “lamellate,” which means “plate or leaf-like” https://bugguide.net/node/view/110081.  The legs are spiny and the feet/tarsi are clawed (all the better to hang on with, my dear) https://bugguide.net/node/view/1275119/bgimage.  Several sources said that the beetles may resemble a wasp while in flight (maybe because of the dangling legs?).

The BugLady does not garden.  She puts her geraniums out on the porch in May, waters them when she thinks of it (they’re very patient), and hauls them back in at the end of October, at around midnight as the first killing frost is descending, and she wouldn’t know what to do with a rose bush if she had one.  Rose chafer beetles feed on the leaves and flowers and maybe the nectar and pollen of lots of different kinds of plants.  Their jaws are weak, so they eat the tender tissue between the leaf veins, skeletonizing the leaf; they make holes in petals; and they eat soft fruits like raspberries and grapes. 

Some sources say that the beetle is only a slight nuisance, doing mainly cosmetic damage; others give instructions for all-out warfare.  Their populations wax and wane, and when there’s a Rose chafer population boom, the beetles may consume a substantial portion of a leaf’s photosynthetic surface and may also impair pollination.  Plus, they may feed in groups.  Interestingly, the North Carolina State Extension write-up about Rose chafers calls them a “relatively minor pest of roses that at one time was apparently much more abundant.

With many insect “pests,” it’s the larvae that do the most damage, but with the chafers, it’s the adults who are the problem.  Rose chafer larvae feed underground on the roots of grasses and other plants, and although a bumper crop of larvae can stunt a plant, they don’t seem to be a real threat to turfgrass or ornamentals. 

Rose chafers can be seen during June and July here in the North.  The plants that they feed on also serve as Social Clubs where males and females meet and mingle https://bugguide.net/node/view/265114/bgimage.  When this “What’s going on here?” picture https://bugguide.net/node/view/120287/bgimage was posted on bugguide.net, entomologist Eric Eaton responded “I don’t think they are ‘eating’ the milkweed. This kind of aggregation is usually associated with mating or “sleeping.”  This seems to be another example of insects chewing on plants; plants releasing volatile compounds to discourage that; and those compounds, perversely, attracting a crowd.  The Rose chafers use their antennae to key in on those plant “odors.”

The female oviposits in the soil, digging down as far as six inches below the surface (!!!), which is why she prefers plants that grow in sandy soil.  She may lay from six to forty eggs, and when they hatch in a few weeks, the larvae locate roots to feed on.  They will move up and down in the soil, depending on soil moisture and soil temperature, and they will overwinter deep in the ground, below the frost line, moving up toward the surface to pupate when the earth warms in spring. 

Many of the scarabs are nocturnal, but Rose chafers are abroad during the day.  They are strong fliers.

Rose Chafer Surprise:  Rose chafers produce cantharidin, a caustic chemical mainly found in beetles in the blister beetle family Meloidae (see https://uwm.edu/field-station/blister-beetle/)!  Although the author of one gardening blog noted that he had been picking them off of plants for decades with no ill effects (the skin on our fingers is pretty tough), he joined the chorus of authors who stressed that the beetles are poisonous to chickens and other birds.

In his “Living with Insects” blog, entomologist Jonathan Neal explains “Their toxicity to chickens led to one of the early scientific studies of toxins in insects. In 1909, George Lamson, Jr, of the Connecticut Agricultural Experiment Station investigated reports of a flock of chickens that died after feeding on the abundant Rose Chafers. Lamson fed Rose Chafers to chickens and determined the numbers required to kill week-old (15-20 Chafers) and 3-week-old chickens (25-45 Chafers). In the early 1900s, chickens were commonly allowed to range free and could easily consume large numbers of Rose Chafers in years with high populations. Lamson recommended that chickens be excluded from areas that contained large numbers of Rose Chafers.  Lamson made an extract of Chafers and demonstrated that the extract was toxic to both chickens and rabbits. These tests proved that the deaths were due to a chemical toxin and not a physical effect from the insect spines or other physical properties. Lamson reported his findings in the Journal “Science” in 1916.”

Kate Redmond, The BugLady

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

Bug o’the Week – Mid-summer Scenes

Bug o’the Week

Black-margined Loosestrife Beetle

Howdy, BugFans,

Purple loosestrife is a beautiful plant, with great wands of magenta flowers waving in the breeze.  Some say that, like a long list of other invasives, it entered the country in the ballast of ocean-going ships; others say that it was imported deliberately because it’s a medicinal plant as well as a great honeybee plant.  The BugLady knew a beekeeper who seeded purple loosestrife from the back of his snowmobile one winter, before he knew better (repent at leisure).  At any rate, it’s been here for 150 years or so, but it really started getting our attention in the 1970’s.  On its home turf, it exists in proportion to other wetland plants; here, it crowds out native vegetation, its dense stands discourage nesting waterfowl, and it’s not used by wildlife as a food plant (insects sure love the flowers, though). There are native loosestrifes, but they’re not invasive.

ARROW CLUBTAIL:  In early July, the BugLady came across this just-emerged dragonfly sitting on a stalk in the Milwaukee River.  She photographed it for half an hour as it lengthened and strengthened and spread its wings and grew its abdomen.  She guarded it from marauding geese and grackles.  And she watched as it took its maiden voyage, eight feet straight up and true – into the beak of a swooping Cedar Waxwing.  She may have used a few bad words. 

JAPANESE BEETLE   Precarious as this bundle of beetles looked, it kept its shape as it fell off and into the grasses.  In order to jump-start her love life, a female Japanese beetle may use “come hither” pheromones, but this aggregation of beetles was probably initiated (inadvertently) by the plant itself.  Research suggests that a female Japanese beetle chewed on a leaf, and the leaf gave off signature chemicals (OK – feeding-induced plant volatiles), and that instead of repelling the beetles, the scent attracted more beetles, both male and female, to feed.  And, since all those guys and gals are in the same neighborhood……… 

MAYFLY MOLT:  BugFan Freda sent this amazing “What-is-it?” picture recently, taken from a canoe on the Milwaukee river.  Mayflies (called “lake flies” regionally) emerge from their watery cradles by the googol.  Their lives are brief, averaging only three days (not coincidentally, the name of the mayfly order is Ephemeroptera).    

Mayflies are the only insects that shed their skins after they reach the winged adult stage (silverfish shed as adults, too, but they’re spindle-shaped and wingless).  The mature mayfly naiad https://bugguide.net/node/view/517056/bgimage crawls out onto a plant or rock and sheds its final skin (exuvia), emerging as a form called a subimago (or a “dun” if you’re a fly fisherman) that is cloudy-winged, dull in color, weak-flying, and not ready to reproduce.  The sub-imago rests (often overnight) and then sheds again, this time into a mature adult/imago with shiny wings (a “spinner” to fishermen).  Here’s a typical adult/imago https://bugguide.net/node/view/933725/bgimage.  No – scientists do not know how this pre-adult stage benefits the mayflies – lots of insect groups apparently has a subimago stage in ancient times, and most have dropped it from their repertory. 

Freda’s picture shows the exuviae of lots of sub-imagoes – it must have been an amazing sight to see!  Scroll down this series of pictures of that final shed – http://www.troutnut.com/article/10/pictures-of-mayfly-dun-molting-to-spinner.  

DOGBANE LEAF BEETLE:  Its fabulous, shimmering exterior is all done with mirrors (complex nanoarchitecture).  Light is bent when it hits small, randomly-tilted plates that sit between the pigment layer and the top layer of the beetle’s cuticle, and the beetle’s color changes depending on the angle of the eye of the beholder.  What good is that glow?  Rather than being an aid in courtship or a warning of the beetle’s toxicity (and this particular beetle is, but not all iridescent insects are), this fiery iridescence actually camouflages it.  To test the hypothesis, researchers disguised meal worms with beetle elytra (the hard outer wings) – some shiny and some not – and then hid them.  Birds found and ate 85% of the “dull-winged meal worms,” but only 60% of the “iridescent meal worms,” and the scientists themselves found it difficult to locate the shiny ones. 

STREAM BLUET AND MAYFLY: In order to make it to adulthood, a mayfly naiad must avoid being eaten by fish and a variety of insects during its aquatic stage, and by fish, birds, fishing spiders, frogs, and other predators as it completes both of its molts.  When it takes to the air, more predators await.  This mayfly became lunch for a Stream Bluet damselfly.  

DOODLEBUG:  The BugLady found this doodlebug on the dunes at Kohler-Andrae State Park in mid-July, plying its trade.  She looked into lots of inverted, sandy cones before she found one that held prey – in this case, a small spider.  The doodlebug will grow up to be an antlion https://bugguide.net/node/view/1708468/bgimage.  For an account of the life of a doodlebug, see https://uwm.edu/field-station/spotless-antlion/.  

SAWFLY:  Sawflies are not flies, but are primitive wasps with no stingers (as she did when she wrote her first episode about sawflies in 2009 https://uwm.edu/field-station/sawfly/, the BugLady recommends reading the sawfly chapter in David W. Stokes’ excellent A Guide to Observing Insect Lives).  Sawfly larvae look a lot like butterfly and moth caterpillars, but there’s a difference in the arrangement and types of legs.  This beauty just might be the Poison ivy sawfly (Arge humeralis), whose pretty cute offspring the BugLady is going to have to keep a cautious eye out for https://bugguide.net/node/view/826616/bgimage.  “Sawfly” because the female uses a saw-like structure at the end of her abdomen to cut slots in vegetation to lay her eggs in.

BLACK SWALLOWTAIL CATERPILLAR: While the BugLady was photographing the sawfly, she noticed a prickly head among the Queen Anne’s lace florets, so she bent the stem sideways to see what it was.  There was a cute little jumping spider under there, too, which she hoped did not have designs on the caterpillar.  Black Swallowtails lay their eggs on plants in the carrot family, and most gardeners who plant dill are familiar with them (and, the BugLady hopes, are generous enough to share). 

BLUE MUD DAUBERS are all over the Queen Anne’s lace these days.  Adults cruise the flower tops, sipping nectar and looking for spiders to cache in the egg chambers of their offspring, who will grow up on protein but eschew it as adults.  Sometimes the wasps pick spiders right off of their webs, and they especially like to collect Black widow spiders (which are here in God’s Country but are rare https://bugguide.net/node/view/1876965/bgimage).  They grab spiders with their mandibles https://bugguide.net/node/view/1268654/bgimage and paralyze them with a sting, but they don’t bite people, and you have to rough one up considerably before she’ll sting you.

EMERALD ASH BORER:  The BugLady loves ash trees, but these days, the landscape is littered with their skeletons.  The first Emerald ash borer was detected in Wisconsin in Ozaukee County during the summer of 2008, though the EABs had undoubtedly been around for a few years before that.  The picture shows an ash that is fighting for its life, a battle that it will not win.  The top of this ash is dead, because the EAB larvae’s tunnels (galleries) just below the bark interfere with the flow of nutrients between the crown of the tree and its roots.  The stressed tree responds by growing a bunch of shoots (called epicormic sprouts) from dormant buds in the bark of the trunk.  The leafy sprouts, which are below the EAB damage, will allow the tree to photosynthesize – for a while.  Read about EABs in a previous BOTW.https://uwm.edu/field-station/emerald-ash-borer-redux-family-buprestidae/.  EABs are, undeniably, beautiful beetles https://bugguide.net/node/view/1770902/bgimagehttps://bugguide.net/node/view/1233730/bgimagehttps://bugguide.net/node/view/938332/bgimage

SIX-SPOTTED FISHING SPIDER:  Moving from a “solid” water lily leaf to a liquid substrate is no trick at all for a Six-spotted Fishing spider (the six spots that give it its name are on its underside) – in fact, it has more moves on the water than it does on dry land.  It can walk, run, sail, or skate over the surface film and can dive under it, too. 

GIANT SWALLOWTAIL: If there’s anything more stunning than a couple of Giant Swallowtails dancing in the air over purple coneflowers, the BugLady doesn’t know what it is. 

Kate Redmond, The BugLady

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

Bug o’the Week – Early Summer Scenes

Bug o’the Week

Black-margined Loosestrife Beetle

Howdy, BugFans,

Purple loosestrife is a beautiful plant, with great wands of magenta flowers waving in the breeze.  Some say that, like a long list of other invasives, it entered the country in the ballast of ocean-going ships; others say that it was imported deliberately because it’s a medicinal plant as well as a great honeybee plant.  The BugLady knew a beekeeper who seeded purple loosestrife from the back of his snowmobile one winter, before he knew better (repent at leisure).  At any rate, it’s been here for 150 years or so, but it really started getting our attention in the 1970’s.  On its home turf, it exists in proportion to other wetland plants; here, it crowds out native vegetation, its dense stands discourage nesting waterfowl, and it’s not used by wildlife as a food plant (insects sure love the flowers, though). There are native loosestrifes, but they’re not invasive.

STILT BUG ON FERN: This started out as a fern fiddlehead picture – the BugLady did not see the stilt bug when she took the picture, it was one of those happy surprises that photographers get when they put an image up on the monitor.  Most stilt bugs/thread bugs are plant-eaters that supplement their diet of plant juices with the odd, small invertebrate.  Some are more “meat-oriented,” and one species is used to control Tobacco hornworms.

CRAB SPIDER: A friend of the BugLady’s recently asked where all of the beautiful, plump crab spiders are.  They’re here, but they have some growing to do.

KATYDID NYMPH: And another friend, from Southern climes, asked if the BugLady was seeing katydids yet.  Same answer.

TIGER BEETLE: The BugLady loves seeing the flashy, green Six-spotted tiger beetles.  Usually they perch on a bare path, wait until you get too close, fly ahead of you about a foot above the ground, land, and repeat the process when you get too close again.  Until this year, the BugLady had never seen one off the ground, but she’s photographed three in the past month.  Get to know Wisconsin’s tiger beetles at https://wisconsinbutterflies.org/tigerbeetle.

MILLIPEDE ON RUST: Millipedes are decomposers/detritivores, feeding on dung, plant juices, and pieces of dead plant materials like decaying leaves, breaking them down for organisms even smaller than they are.  Some like fungi. 

If you’ve seen the invasive shrubs Glossy and Common buckthorn, you’ve probably seen stems and petioles with a bright orange blob on it.  The blob is a rust – a fungus – called Crown rust (Puccinia coronata).  Buckthorn is one of its hosts, and the alternate hosts are a variety of grasses, including agricultural crops like oats and rye.  If you see grass leaves with thin orange streaks on them, you’re probably seeing a variety of crown rust.  Crown rust has a complicated life cycle (http://www.minnesotaseasons.com/Fungi/Crown_Rust.html ), but the bottom line here is that the rust on buckthorn releases its spores in a soupy, sweet liquid that attracts insects, and the insects carry the spores to rust patches on other buckthorns and fertilize them.  The rust probably doesn’t get much bang for its buck when its spores are eaten by a short-legged pedestrian like a millipede.

BALTIMORE CHECKERSPOT CATERPILLER: The astonishing Baltimore Checkerspot https://bugguide.net/node/view/1771510/bgimage and https://bugguide.net/node/view/1636206/bgimage, and its caterpillar, is one of the BugLady’s favorites.  This caterpillar hatched last summer and munched on its host plant (historically white turtlehead, but in the past 50 years, they’ve adopted Lance-leaved/English plantain, and those are the only two plants a female will oviposit on).  It overwintered as a caterpillar, woke up hungry this spring, and looked around, – no turtlehead in sight yet – so it’s been eating a variety of plants, especially white ash.  Both turtlehead and plantain leaves contain poisonous glycosides (turtlehead has more), allowing the caterpillar and butterfly to get away with their gaudy colors.  And remember – the butterfly (and the oriole) get their names not because they were discovered in that city, but because 17th century English nobleman Lord Baltimore, a familiar figure to the colonists, dressed his servants in orange and black livery. Get to know Wisconsin’s butterflies at https://wisconsinbutterflies.org/butterfly.

MONARCHS: Most of the Monarchs that return to Wisconsin are probably Gen 2 – the second generation north of their wintering ground in Mexico.  There ensues two short-lived generations – Gen 3 and 4 – whose only job is to increase the population, and these two clearly got the memo.  Gen 5, produced in August, is the generation that is signaled by both waning day length and the lowering angle of the sun to migrate instead of reproducing (though there always seem to be a few that didn’t get that memo). 

BEE ON LEATHERWOOD: At a quick glance, you might think that this is a bumble bee, but bumble bees have hairy butts.  The BugLady thought this was a carpenter bee (which have shiny butts), but now she thinks it’s one of the larger mining bees in the genus Andrena.  Leatherwood is a spring-blooming shrub in woodlands – those fuzzy bud scales protect the bud from chilly spring nights.  It gets its name from the fact that its branches can’t be torn off the shrub, and from its strong bark fibers, which were woven into baskets, bowstrings, ropes, and the cords that lashed together canoe frames.  Settlers used its branches when they took their children to the woodshed.  All human use of it is problematic, because its caustic bark raises some serious blisters.

ROBBER FLY: Another bumble bee look-alike.  Bumble bees eat nectar and collect pollen to feed their larvae; robber flies are carnivores.  Laphria thoracia (no common name) can be found on woodland edges from the Mason-Dixon Line north into the Maritime Provinces and west through the Western Great Lakes.  Adult Laphria thoracia eat bees and adult beetles (this one has a clover weevil, but the BugLady recently photographed one with an assassin bug), and their larvae feed on beetle larvae in decaying wood.  Get to know Wisconsin’s robber flies at https://wisconsinbutterflies.org/robberfly  

GOLD-BACKED SNIPE FLY: June is the only month to enjoy these dramatically-colored flies that perch low in the vegetation in moist areas. 

SWAMP MILKWEED BEETLE: The BugLady loves finding these “ladybugs-on-steroids.”  They’re often tucked down into the axils of the milkweed leaves, and when they see company coming, they either duck down deeper into the crevice or they default to the typical escape behavior of an alarmed leaf beetle – they tuck in their legs and fall off the plant.  Their bright (aposematic/warning) colors tell potential predators that they are toxic, due to the milkweed sap they ingest, but damsel bugs, stink bugs, and flower/hover/syrphid fly larvae prey on them nonetheless.  For the full (and fascinating) Swamp milkweed leaf beetle story, see https://uwm.edu/field-station/swamp-milkweed-leaf-beetle/.  

ICHNEUMON WASP: Every year, large and colorful Therion (probably) Ichneumon wasps drift through the vegetation in perpetual motion, legs dangling, taunting the BugLady https://bugguide.net/node/view/739675/bgimage.  They often occur in wetlands, and the BugLady swats mosquitoes and deer flies as she waits for them to show their faces.  Which this one did.

Experienced BugFans are saying, “But, but, but – where are the dragonflies?”  Tune in next week.

Go outside – look for bugs.

Kate Redmond, The BugLady

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

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