Bug o’the Week – Summer Sights – and Sounds

Bug o’the Week
by Kate Redmond

Summer Sights – and Sounds

Howdy, BugFans,

The BugLady took to the trails this summer as much as her shiny, new knee and the oppressive heat and humidity allowed (her preferred maximum temperature is 72 degrees.  The gods didn’t cooperate).  Here are some of the bugs she found.

BLUE DASHER OVIPOSITING – A female Blue Dasher bobs up and down as she looses eggs into the water.  Blue Dashers don’t oviposit “in tandem,” with the male guarding her by maintaining his grip at the back of her head, but the male stays close, flying around her as she dips the tip of her abdomen into the water, and chasing off rival males that would carry her away.

CICADA – When the BugLady was little, the treetops sizzled with cicada calls in August (she called them “hot bugs,” because when they emerged, it was).  The only species she heard back then was the dog day cicada https://uwm.edu/field-station/bug-of-the-week/dogday-cicada-family-cicadidae/, but for the past decade, she has heard fewer and fewer of them each year https://songsofinsects.com/cicadas/dog-day-cicada.  

This year, she has been enjoying the songs of a Linne’s cicada https://songsofinsects.com/cicadas/linnes-cicada and an dusk-calling Scissor-grinder cicada https://songsofinsects.com/cicadas/scissor-grinder-cicada, too, both of whom are southern/southeastern species that are inching north.  Welcome!

CABBAGE BUTTERFLY ON PURPLE LOOSESTRIFE – A dainty, white butterfly on a pretty, fuchsia flower.  Both are non-native (hint: the butterfly’s caterpillar is known as the European cabbage worm), and both are “naturalized,” that is, having been introduced and/or having escaped into the wild, they are doing very well on their own, thank you.  Only a very small percentage of non-native, naturalized species go on to create problems and to get a third label – “invasive.”  For a nice discussion, see https://www.hrwc.org/invasive-non-native-or-naturalized/

EASTERN PONDHAWK AND MEADOWHAWK – It’s a dragonfly-eat-dragonfly world out there.

MILKWEED TUSSOCK MOTH AND CRAB SPIDER – The BugLady has been receiving some queries recently from BugFans whose milkweed is looking pretty ratty.  The culprit?  The Milkweed tussock moth https://bugguide.net/node/view/72813, whose caterpillar is sometimes called the Harlequin caterpillar.  Mom lays masses of eggs, and the caterpillars feed gregariously for a while, skeletonizing leaves by eating the tender tissue between the leaf veins.  Then they go their separate ways and eat the leaves down to their midribs.  Bugguide.net says, in an understatement, that the caterpillars “May defoliate patches of milkweed.” 

Allegedly, they don’t interfere with Monarch caterpillars because they eat the old, leathery leaves that the monarchs don’t, and because they’re gearing up as the Gen 5 Monarchs are readying themselves for their trip south.

No, the BugLady did not see the crab spider, and what looks like an egg sac, when she took the picture.

PICTURE-WINGED FLY – This spiffy fly (genus Rivelli, family Platystomatidae) walks around, twitching its wings constantly, sending semaphore signals to nearby females.  For its story, see https://uwm.edu/field-station/bug-of-the-week/signal-fly/ (only, the BugLady misspelled the family name).  What a treat to watch this little fly strutting his stuff!

WOOD/AMERICAN DOG TICK – Yes, they’re everywhere (they prefer grassy areas and forest edges), and yes, most people feel creepy just looking at a picture of one, feeling the phantom feet of phantom ticks tickling their skin.  Dog ticks need three different hosts to get through their life cycles, and they can spread Rocky Mountain spotted fever as well as Tularemia (but if your dog comes down with Tularemia, it may be playing with the local bunnies).  Various sources say that Wood ticks in Wisconsin don’t often carry diseases and that Rocky Mountain spotted fever (or any Spotted fever rickettsiosis) are (for now) rare here.  They don’t spread Lyme disease.

VIRGINIA CTENUCHA CATERPILLAR –Lepidopterists say that the more spectacular the caterpillar, the more homely the adult, and vice versa  The Virginia Ctenucha moth is one of the exceptions that proves the rule https://bugguide.net/node/view/1991557/bgimage.

The caterpillars are out and about early – this one was photographed in May, but they overwinter as caterpillars, and the BugLady encounters them strolling along on the warm road on a warm day in late winter or early spring.  Adults are large-ish, day-or-night-flying moths that tuck in under a leaf when alarmed.  The “C” is silent. –

WOOLLY ALDER APHIDS AND THEIR ANTS – We’ve seen it before – aphids going about their business, assisted by ants that protect them them in exchange for being able to “milk” them for honeydew, a sugary fluid that is a byproduct of the sap that flows through the aphids when they eat.  Honeydew is an important carbohydrate for the ants that farm aphids and treehoppers.  If you’ve ever seen a leaf whose upper surface looks shiny and sticky, look up under the overhead leaves – they’re probably occupied by aphids.  Bees, wasps, flies, and other insects will visit the leaf to eat honeydew.  The woolly aphid’s wool consists of waterproof, waxy filaments made in glands in the aphid’s abdomen.

EMERALD ASH BORER – They really are lovely, little beetles, with a surprise splash of crimson when their wings are spread https://bugguide.net/node/view/1522143/bgimage.  But the extensive tunnels (called galleries https://bugguide.net/node/view/687825/bgimage) that the larvae make below the bark disrupt the ash tree’s plumbing so that it can’t pump nutrients between its roots and crown. 

SEDGE SPRITES – One of the BugLady’s favorite damselflies, these little beauties are scarcely an inch long. 

WEEVILS ON PURPLE PRAIRIE CLOVER – Purple prairie clover is a lovely, native tallgrass prairie plant.  The early settlers on the Great Plains nicknamed it “Devil’s shoelaces” because this skinny, two-foot-high plant may have roots that are six feet long – roots that grew deep enough to reach through the thick prairie sod to find water.  That magnificent sod resisted the settlers attempts to plow it with their small, cast-iron plows until 1837, when John Deere invented the steel moldboard plow, which he fashioned from an old sawmill saw. 

At the top of the flower, there are two weevils, probably seed weevils in the genus Apion, making whoopie.  Here’s a BOTW about seed weevils https://uwm.edu/field-station/bug-of-the-week/baptisia-seed-pod-weevils/.  No, the BugLady did not see the weevils when she took the picture.  

STAG BEETLE – Yes, the BugLady did see this Stag beetle as it emerged from her lawn one evening in July – the beetle looks big enough to trip over, and she moves like a tank.  Here’s her story https://uwm.edu/field-station/bug-of-the-week/stag-beetle-lucanus-placidus/.

ROBBER FLY – Remember, bumble bees are vegetarians, so if you see a bumble bee with prey, it’s not a bumble bee.  Mimicking a bumble bee is a pretty good survival strategy – no one messes with bumble bees.  This fly is in the genus Laphria, one of the “bee-like” robber flies.  Their larvae live in rotten wood and feed on insects they find there, and the adults often prey on beetles (though the BugLady saw one make a pass at a Sulphur butterfly once).  Robber flies come in a variety of sizes and shapes – for information about Wisconsin robber flies (and butterflies and tiger beetles) see https://wisconsinbutterflies.org/butterfly.

RED-BELTED BUMBLE BEES – are found west of the great plains and across southern Canada and our northern tier of states.  They are one of the short-tongued bumble bees, which means that they prefer “flatter” flowers like clovers, thistles, goldenrods, and asters.  The BugLady doesn’t know where this one was hiking to – she saw several others on flowers in the area.  A little rusty on bumble bees?  Here’s a great bumble bee guide from the Xerces Society: https://www.xerces.org/publications/identification-monitoring-guides/bumble-bees-of-eastern-united-states

Go outside, look at bugs,Professor, Dr. Richard B. Fischer, the content of whose fantastic natural history courses she uses Every! Single! Day!  (right BugFan Mike?)  He would have enjoyed BOTW. 

Kate Redmond, The BugLady

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

Bug o’the Week – the Missouri Bee-killer Robber Fly

Bug o’the Week

the Missouri Bee-killer Robber Fly

Howdy, BugFans,

Robber flies are a very cool bunch of flies that we have visited a number of times in the past.  To appreciate the array of sizes and shapes and colors of Wisconsin robber flies from the tiny “Gnat ogres” https://bugguide.net/node/view/2036908/bgimage, to the bumble bee mimicking Laphria https://bugguide.net/node/view/612780, to the Giant robber flies in the subfamily Asilinae (like today’s star) https://bugguide.net/node/view/1424049/bgimage, visit the robber fly corner of the wisconsinbutterflies.org website https://wisconsinbutterflies.org/robberfly.

Besides being awesome-looking, these “bearded” flies (sometimes called Assassin flies) are predators, and they are not shrinking violets.  In the Field Guide to the Insects of North America, Eric Eaton says that “Robber flies (family Asilidae) are to other insects what falcons are to other birds.”  In an article published in the Bulletin of the Brooklyn Entomological Society in 1949, S. W. Bromley tells us that “Linneaus … gave this group of flies the name Asilus (the ancient name for flies which tormented cattle) in the belief that they were molesters of stock and cattle, a habit in which no robber fly today is known to indulge.”

Robber flies’ modus operandi is to spot an insect from their perch, grab it (and they will go after insects larger than they are), inject it with saliva to both kill it and soften its insides, and then perch and ingest the liquid through a tube called the hypopharynx.  They eat lots of insects that are agricultural pests, but they haven’t been formally deployed as biological controls because they are equally likely to eat honey bees and Monarch butterflies.  

There are about 1000 species of robber fly in North America, and the Missouri bee-killer (Proctacanthus milbertii), akaMilbert’s Proctacanthus, is one of 17 members of its genus north of Mexico.  Bromley notes that “In Southern Alabama, Col. S. F. Blanton stated that it has received the common name of ‘Boo-hoo fly.’”   

The spectacular Missouri bee-killer is found from sea to sea, and north and south of our borders in sort of a checkerboard pattern https://bugguide.net/node/view/46891/data (the range maps in bugguide.net come with a disclaimer that says, “The information below is based on images submitted and identified by contributors. Range and date information may be incomplete, overinclusive, or just plain wrong.”).  According to Bromley, “Milbertii has for its habitat fields and pastures where the soil contains a considerable admixture of sand.”  It’s often found around goldenrod, and it’s pretty well camouflaged when it sits on the ground surrounded by dry goldenrod leaves.  The Missouri bee-killer is a late-season robber fly, and it’s one of the species that the BugLady found in the dunes at Kohler-Andrae State Park. 

There’s some variation in color – the beard is creamy white, but some individuals aren’t as maroon than the one the BugLady found https://bugguide.net/node/view/230984/bgimage.  They are active and noisy fliers, and they like to rest on open ground. 

Males are territorial and will chase rival males.  Robber fly courtship is a no-frills affair – he approaches her much like he approaches prey.  After mating (https://bugguide.net/node/view/977130/bgimage), she works her abdomen barely into the soil or sand https://bugguide.net/node/view/1168742/bgimage and lays her eggs.  She visits flowers before ovipositing because for best results, she must take in both protein and sugar before she oviposits.  The larvae live in the soil and prey on invertebrates they find there, and they may also nibble on decaying plant material.  In some robber fly species, the larva lives in the soil for up to three years before it pupates.  

In a 1975 article in The Great Lakes Entomologist, Norman T. Baker and Roland L. Fischer wrote that “P. milbertii exhibits a very interesting defensive reaction when attacked by another fly. The attacked fly nearly always spreads its legs and wings outward and upward and curves the abdomen upward. Generally the fly turns to face the attacker and then tilts backward allowing it to better fend for itself. Usually the wings are buzzed in short bursts.”

Although some closely-related robber flies do concentrate more on them, Missouri bee-killers are generalists whose diet doesn’t include many honey bees (only 4%, according to one study).  Grasshoppers https://bugguide.net/node/view/144982/bgimage and moths https://bugguide.net/node/view/990141/bgimage make up about three-quarters of their food, and they also prey on butterflies, beetles, bugs, bees (including bumble bees https://bugguide.net/node/view/141843/bgimage), and flies, and they’re not above a little cannibalism.  In a study area in the Nebraska sandhills, researchers counted 437 Missouri bee-killers per hectare (one hectare is a little less than 2.5 acres) and 64,000 grasshoppers from 23 species per hectare.  The flies devoured one to two grasshoppers per day, each, consuming an average of nearly 2% of the population of adult grasshoppers daily. 

They fly fast, pick their prey out of the air, and land to feed.  They wrap all six legs around it and administer a killing jab behind the prey’s head, often lying on their side until the prey is dead https://bugguide.net/node/view/144985/bgimage.  They pierce their prey often as they feed in order to reach all its nooks and crannies, manipulating it with their forelegs.  If you must handle a robber fly, handle it with care, because the larger species can jab painfully. 

Baker and Fischer’s documentation of the daily routine of Missouri bee-killers included observations of its sleep habits.  They wrote “These flies are quite active as long as the proper habitat is hot and sunny. When dusk approached, and the sun no longer shone on the habitat of P. milbertii, the flies cease all activity. Attempts to discover where they spent the night were nearly futile until it was discovered that the flies were resting in or under dead leaves beneath nearby trees or bushes. When the sun set the flies “entered a stupor” and became very inactive. If disturbed they would buzz their wings for a second or two and then again become inactive. Perhaps the buzzing will frighten a possible predator. The positions these flies may assume are often ridiculous. They appear to be dead. In one instance a male was discovered “standing on his head” and supported only by his front legs. Hull (1962) has also observed this behavior and interpreted it as ‘death feigning.’”  Here’s an early morning shot https://bugguide.net/node/view/835010/bgimage

Go outside – look for bugs – it’s not too late!

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

Early Summer Scenes

Howdy, BugFans,

Well, the sun has solsticed, and it’s all downhill from here.  Our pre-Christian, Germanic ancestors, who were more intimately attuned to the rhythms of the sun, correctly celebrated the winter solstice, aka Yule (which may have come from the Norse word houl, which referred to the sun as the wheel that changed the seasons).  They recognized that the winter solstice marked a turning point that would lead to longer, warmer days.

In the BugLady’s neck of the woods, the insect world is dominated these days by mining, sweat, and bumble bees and by lots of flies, including a big hatch of mosquitoes that timed their appearance to coincide with the Riveredge Butterfly and Dragonfly count (causing the BugLady to move along the trail rather smartly).  Here’s what she’s been seeing in the run-up to summer.

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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