Bug o’the Week – Cereal bug

Bug o’the Week
by Kate Redmond

Cereal bug

Greetings, BugFans,

The BugLady loves finding an insect she’s never seen before.  When she saw it walking along a cordwalk (boardwalk on sand) in the dunes at Kohler-Andrae State Park, she knew that this guy/gal was in the stink bug family (Pentatomidae), but it’s more spindle-shaped and lacks the “shoulder pads” of a generic stink bug https://bugguide.net/node/view/2125170/bgpage (younger BugFans may have to Google “shoulder pads”).

It turned out to be a stink bug in the large subfamily Pentatominae and in the very small tribe Aeliini, which has only 37 species worldwide.  There are 8 species in the tribe in North America (in two genera), and this is the only species in its genus here.  The BugLady borrowed the name “Cereal bug” from one of the European species because she couldn’t find a common name for it.

Cereal bugs (Aelia americana) have an odd, patchwork range (based on pictures submitted by bugguide members https://bugguide.net/node/view/668478/data) that lies mostly west of the Mississippi – from British Columbia to Arizona to Alabama to Michigan, and within their range, they’re not very common.   

They feed by day on the ripening seeds of grasses, including agricultural crops like wheat, barley, and rye (https://bugguide.net/node/view/2241245/bgimage).  The BugLady found some brief write-ups about them from grain-producing areas of the upper Great Plains into Canada, but they’re not common enough to be a nuisance here.  Like other Hemipterans, they insert their beak into the plant, pump in some digestive juices, and suck out the softened tissue.     

Eggs are laid in late spring and early summer, and the nymphs reach maturity by fall and overwinter as adults.

[In the “Eternal Job Security” category that is insect taxonomy, the BugLady found a paper titled “Opening Pandora’s box: molecular phylogeny of the stink bugs (Hemiptera: Heteroptera: Pentatomidae) reveals great incongruences in the current classification.”  It reminded her of a quote she found years ago when she was writing about a moth, “The genus Haploa …… has furnished a great deal of amusement to classificationists.”  Presumably, the Hemiptera taxonomists are similarly amused.]  

Along with grasses, they have been collected from apple trees in orchards, and according to a paper published by the Michigan Entomological Society, adults have been found overwintering in grass clumps and under mullein leaves. 

Some genus members are considered pests in the Middle East and around the Mediterranean, though, and the BugLady found a lot more information about a closely-related-and-very-similar-looking European species called (wonderfully) the Bishop’s mitre (Aelia acuminata) than she did about our domestic species, but she suspects that the two are up to some of the same tricks. 

The Bishop’s mitre (a mitre/miter is a bishop’s peaked, ceremonial hat) is found feeding on grasses in dry meadows and damaging cereal crops across Europe, North Africa, and northern Asia, and the britishbugs.org website added that they may be found in sand dunes, too.  One British site said that the bugs resemble a grass seed (https://www.britishbugs.org.uk/heteroptera/Pentatomidae/aelia_acuminata.html).  They winter in grain fields, in leaf litter and other sheltered spots, and they migrate to wheat fields in spring when the wheat shoots appear (they’re good flyers).  Before the seeds are formed, they feed on juices from the stems of young plants.  After harvest, they move to wild grasses.    

Studies have shown that they enter diapause/dormancy/developmental arrest when the weather gets too hot in summer and go into hibernation when the weather gets too cold in fall.  The increasing day lengths of spring stimulate egg-laying, but if there’s a cold snap, females will stop ovipositing. 

Aelia americana was named by a British entomologist named William Sweetland (W.S.) Dallas (1824 – 1890).  He published a book in 1857 called Elements of Entomology: An Outline of the Natural History and Classification of British Insects which is still in print today and about which the folks at Amazon say “This book is an essential resource for amateur and professional entomologists alike.  This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it.” 

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 – 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 – The Twelve Bugs of Christmas 2022

Bug o’the Week

The Twelve Bugs of Christmas 2022

Greetings of the Season, BugFans,

Wow!  The 10th annual installment of The Twelve (or Thirteen) Bugs of Christmas!  The Bugs of Christmas features shots, taken throughout the year, of insects and spiders who have already had their own BOTW, but who posed nicely.

The next two paragraphs were borrowed from Christmas 2016, because the BugLady is still amazed by the history of this ubiquitous Holiday Classic.

The Twelve Days of Christmas” is an English carol that was probably borrowed from the French and that was originally an acapella chant/call-and-response/children’s memory game.  There’s an alternative explanation about the various lords, rings, etc. being Christian code words for catechism during a time of religious repression (which seems a bit like playing Beatles songs backwards).  It first appeared in writing in 1780, and there were (and still are) many variations of it, though the words were more-or-less standardized when an official melody was finally written for it in 1909 (and the insect verse was, alas, dropped.  “Thirteen Bugs a’ buzzing”).

See https://en.wikipedia.org/wiki/The_Twelve_Days_of_Christmas_(song) so you can hold your own in Holiday Trivia at parties (I’ll take Christmas Songs for $300, Alex).  With apologies to all those Lords a’ Leaping, it’s time once again to celebrate a year of bugs with this baker’s dozen collection of the beautiful, the odd, and the mysterious.  Gifts.  Right under our noses.  All the time.

POTTER WASP – Throughout this BOTW series, we have noted the many places where insects deposit their eggs – in plant stems, in underwater vegetation, in dead trees, in flower buds, in mushrooms, in the BugLady’s wind chimes, in carcasses, in holes and tunnels underground, in other insects, in cells made of wax or paper, in egg sacs.  The BugLady’s favorite is the small, mud pot attached to a twig or leaf by a potter wasp. 

SEDGE SPRITE – The BugLady is a tall person, and Sedge Sprites (her favorite damselflies) are tiny damselflies, barely an inch long, that mostly fly at altitudes lower than her knees.  Photographing one involves tracking an insect the size of a sewing needle through sedges and other boggy vegetation.  What a beauty!

BUMBLE BEE – The plant is called Common Hound’s-tongue (Cynoglossum officinale) (aka houndstooth, dog’s tongue, Gypsy flower, and Rats and Mice (because it’s said to smell like them).  Lots of small flowers on a plant that may grow 4 feet tall.  It’s from Europe; it probably came over in the 19th century in a bag of agricultural seed, and it’s considered a noxious weed in parts of North America (but it’s rare in Ireland).  It contains chemicals (alkaloids) that are toxic to livestock, its bristly seeds are not wholesome to ingest, and they irritate the skin, too.  Historically, it was used as a cure for madness and to treat inflammatory diseases, lung issues, and “it heals all manner of wounds and punctures, and those foul ulcers that arise by the French pox’” (Culpeper’s Complete Herbal).

The bumble bee doesn’t know any of that, and doesn’t care.

LADYBUG and SHINING FLOWER BEETLE – Multicolored Asian Ladybird Beetles come in a variety of shades of red and orange with spots ranging from zero to many, but you can tell them by the “W” or “M” on the thorax (depending on whether they’re walking toward you or away from you).  Adults eat aphids and scale insects, and their larvae eat even more aphids and scale insects, and some eggs of butterflies and moths.  The BugLady couldn’t find anything that suggested that they might chow down on a small beetle like this Shining flower beetle, but the ladybug sure was interested in it and followed it all around the surface of the leaf.

GIANT ICHNEUMON WASPS are among the BugLady’s favorite insects (Why?  See https://uwm.edu/field-station/giant-ichneumon-wasp/).  There are two species of rust and yellow Giant Ichneumons around here https://bugguide.net/node/view/1701906/bgimage, plus Black Giant Ichneumonid Wasp https://bugguide.net/node/view/1742321/bgimage.  This is a male Black Giant Ichneumonid Wasp.  

SPIDER WEB – an abandoned trap web, toward the end of summer.

DARNER EXUVIA – In today’s usage, the empty, shed skin of an insect or spider is (mostly-but-not-always) called an exuvia (Pl. exuviae), from the Latin for “things stripped, drawn, or pulled from the body”.  The BugLady, who likes etymology as well as entomology, wanted to find out more about the word, so down the rabbit hole she went.  She discovered that even her two favorite dragonfly and damselfly books don’t agree with each other. 

The British use “exuvium” for the singular and “exuvia” or “exuviums” for the plural.  When she did a bit more delving into “exuvium,” the BugLady found this awesome excerpt from a letter written by Sir Thomas Browne to his son Thomas, dated May 29, 1679: “I have sent you, by Mrs. Peirce, a skinne of the palme of a woemans hand, cast of at the end of a fever, or in the declination thereof; I called it exuvium palmæ muliebris, the Latin word being exuvia in the plurall, butt I named it exuvium, or exuvia in the singular number.  It is neat and is worthy to be showne when you speake of the skinne. …. A palmister might read a lecture on it.” 

A post in a bugguide.net discussion further muddies the waters by stating that the cast-off skin of an insect should be referred to in the plural (exuviae) because “a single cast skin is a collection of insect parts and is thus an exuviae.” 

There’s no logical equivalent in Classical Latin, but Scientific Latin takes liberties with the Classical.  The entomology community tacitly agrees that it’s a “we-know-it’s-not-correct-but-we’re doing-it-anyway” situation. 

The snail had nothing to do with the emerging dragonfly and, the BugLady guesses, is passing by.

BUMBLE FLOWER BEETLES – When the BugLady found some of these and wrote about them one fall https://uwm.edu/field-station/bumble-flower-beetle/, BugFan Chris told her that they’re also around in the spring.  Sure enough – she spotted this one in mid-May. 

MOURNING CLOAKS aren’t splashy, and they eschew wildflowers in favor of dripping sap, but they’re pretty spiffy nonetheless, and they’ve got a cool life story.  In a group (the order Lepidoptera) where the adult portion of a lifespan is usually measured in a few, short months, these are long-lived and complicated butterflies.  They overwinter as adults, mate, and lay eggs in spring.  Their offspring feed on willow leaves, form chrysalises, and emerge as adults in late spring or early summer.  After feeding for a while, they go into a state of aestivation (summer dormancy) to avoid wear and tear.  They wake in fall, feed some more, and then overwinter as adults in a state of suspended animation called diapause, which is similar to hibernation, tucked up in a cloistered spot called a hibernaculum that shelters them from the elements, and protected from the effects of freezing by glycerol (antifreeze) in their bodies.  They may fly during a January thaw or on mild days in late winter, but they can reenter diapause when the temperature drops.  When they emerge and mate in spring, they’re about 10 months old. 

This pretty CLICK BEETLE by the name of Ampedus sanguinipennis (sanguinipennis means “blood wing”) is found in wooded areas – its larvae develop in, feed on, and then pupate in very rotten wood, emerging as adults by fall, but hunkering down within the pupal cell for the winter.  Adults are pollen feeders that shelter under loose bark.  Somewhere in its travels, this beetle encountered some mites, which hitched a ride.  The harmless transporting of other organisms is called phoresy.  Here’s a glamour shot https://bugguide.net/node/view/20063.

If you’re a CRAB SPIDER and you don’t spin trap webs, you need a different strategy for finding dinner.  Crab spiders employ camouflage and ambush.  The flower is a tallgrass prairie plant called leadplant. 

COMMON GREEN STINKBUGS (Chinavia hilaris) are considered persona non grata in agricultural fields and orchards because both the nymphs and the adults feed on fruit and developing seeds.  And yet.  Hilaris means “lively” and “cheerful,” and that’s the vibe this stink bug was sending on a sunny day.

And an EASTERN AMBERWING Dragonfly in a pear tree. 

Kate Redmond, The BugLady

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

Bug o’the Week – Two Stink Bugs

Bug o’the Week

Two Stink Bugs

Howdy, BugFans,

The BugLady thinks stink bugs are cool https://bugguide.net/node/view/1685642/bgimage, and she loves finding species she hasn’t seen before.  This year, she saw two new ones – the first one in a sand dune, and the second in a bog – but she suspects that habitat is secondary in the stink bugs’ game plan to the availability of food.

They’re called “stink bugs” because they have glands in the thorax that produce, as Eric Eaton says in the Field Guide to Insects of North America, “volatile aromatic compounds sure to repel all but the most desperate predators.”  One author adds that “Stink bugs can smell pretty bad. Even my hens turn up their beaks when one crawls by…..”

Some stink bugs are predaceous, but most are plant-eaters, and many, including today’s pair, aren’t picky about the plant species they feed on.  They are “true bugs” in the order Hemiptera (Hemiptera means “half-wing,” which refers to wings that are leathery at the near end and membranous at the far end https://bugguide.net/node/view/471688/bgimage), and they’re in the family Pentatomidae.

Like other Hemipterans, they feed by puncturing their food with their piercing-sucking mouthparts https://bugguide.net/node/view/1864018/bgimage, injecting enzymes that soften the tissues, and then sucking out the contents.  If they’re feeding on, say, a peach, the puncture may inadvertently inoculate the immediate area with bacteria, causing rot, and soft fruits develop “dimples” called cat-facing, both of which make the fruit less attractive in your grocery store. 

Both of today’s species are divided up into several subspecies, and the BugLady was surprised to see that there were differences within each species not only in color, but also in the spiny-ness of their “shoulders,” depending on their geography and even season.  

RED-SHOULDERED STINK BUGS (Thyanta custator) occur across North America from Canada to Guatemala, and from sea to shining sea; the BugLady found this lovely, pastel stink bug in the dunes.  There are three subspecies, the most common of which is Thyanta custator accera.  

At about ½” long, Red-shouldered stink bugs (Thyanta custator) are fairly large, as stink bugs go.  They come in varying shades of green and tan, and the red on their shoulders can be very conspicuous or absent https://bugguide.net/node/view/1228797/bgimagehttps://bugguide.net/node/view/253073,

https://bugguide.net/node/view/1035753/bgimage, , https://bugguide.net/node/view/401270/bgimage

And so can their spines https://bugguide.net/node/view/1312629/bgimage.

Young stink bugs (nymphs) are often much more colorful than their elders https://bugguide.net/node/view/710344/bgimagehttps://bugguide.net/node/view/768528/bgimage.   

Females lay clusters of barrel-shaped eggs on the leaves and stems of plants https://bugguide.net/node/view/1625073/bgimage, and the nymphs feed on young leaves, buds, flowers, and developing seeds of their natal plants.  When they mature (in about a month) and have functional wings, they spread out to neighboring plants.  The RSSB has been found on many species of plants in more than a dozen plant families, some of them agricultural crops like wheat, beans, alfalfa, some fruits, and hemp, but they’re not on USDA Wanted Posters because they mainly damage seed production.

They overwinter as adults in leaf litter, but like other stink bugs, they will happily spend the colder months in a warm house.  In spring, they awake and spread out to find vegetation – and other RSSBs https://bugguide.net/node/view/41009/bgimage.   

The second species was the nymph of (probably) a DUSKY STINK BUG (Euschistus tristigmus luridus). Of the two forms/subspecies in North America, Euschistus tristigmus luridus) occurs the farthest north.  The subspecies that’s found in the South and into Central America, Euschistus tristigmus tristigmus, is smaller, and the front edges of its thorax are pointier https://bugguide.net/node/view/1993459/bgimage.  Dusky stink bugs are found in grasslands, woodlands, and riparian edges (and, apparently, bogs).

Quick Euschistus tristigmus luridus Dictionary Side Trip: Five hundred years ago, “lurid” meant “pale (so pale that you glow in the darkness), sickly, the color of bruises, ghastly, or yellowish.”  By the 1700s, its meaning was shifting and the word was used to describe the faint red glow of a fire shrouded by smoke.  In about 1850, its meaning changed again, to something like today’s common usage – “sensational, shocking, horrifying, or bright, intense, and vivid.”  

Here are the three spots suggested by “tristigmus,” though not all individuals have them https://bugguide.net/node/view/73486/bgimage

The broad strokes of the Dusky stink bug’s natural history are similar to those of the RSSB, with adults overwintering and laying eggs as vegetation starts growing in spring.  It uses a different set of food plants than the RSSB, including some wildflowers like clover, goldenrod, and Black-eyed Susan, some ash and oak species, fruits like blackberries and red delicious apples, and some field crops (and bugguide.net says that it is “occasionally predaceous”). The BugLady sees nymphs of other bugs, like leaf-footed bugs, near bird droppings; they get minerals from them, and she wonders if stink bugs do, too.  Like the RSSB, it has little to no economic impact (and it sure is cute).

The BugLady gives thanks for dragonflies (and she would like to know where the mosquito that she photographed in her house on November 11 has been for the past month).

Kate Redmond, The BugLady

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

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