Tag: bug of the week

Bug o’the Week – Common Green Darner rerun

Bug o’the Week
by Kate Redmond

Common Green Darner rerun

2026

The BugLady checked the (highly searchable) website of the Wisconsin Odonata Survey (https://wiatri.net/inventory/odonata/) to see if anyone had reported a Common Green Darner yet.  They are early migrants from the southeastern part of the country, traveling north with the warm weather, and they’re often the first dragonfly species of the year.  Here’s an episode about them from nine years ago.  New pictures, a few new words.


2017

A Common Green Darner was reported near La Crosse (WI) on March 24 of this year, and a few others have been seen since then (and even though the winter of 2016-17 has been “Winter Lite,” the BugLady is ready for spring and dragonflies).  The BugLady wrote very brief biographies of the green darner in 2010, in BOTWs about spring dragonflies and about dragonfly swarms, but there’s much more to the Common Green Darner story.

They are in the darner family Aeshnidae, a group of large, powerful dragonflies (“darner” because their long, darning needle-like abdomen has led to folk tales about their sewing people’s lips or ears shut). 

Most of our Wisconsin darners are in the famously-confusing mosaic darner genus Aeshna.  Common Green Darners (Anax junia) (“Lord of June”) are one of two species of Anax darners found in the state.  Common Green Darners are, well, very common, not just here but across the country.  And Central America.  And Hawai’i.  And Canada.  And there are populations in Tahiti and the West Indies.  And strong winds have blown individuals to Great Britain, China, and Russia.  The other Anax, the stunning Comet Darner (Anax longipes) is a rare visitor and even rarer breeder in Wisconsin https://www.bugguide.net/node/view/1865910/bgimage.   

Common Green Darners are big, with a 3” long body and a 3 ½” wingspan, and their striking “wrap-around” compound eyes may be made up of as many as 50,000 simple eyes apiece.  Their wings often show a golden tinge in flight. They practice sexual dimorphism – both males and females have a green thorax, but males have a predominantly blue abdomen with a purple stripe, and females have a maroon/rust-colored abdomen with a darker stripe.  Tenerals (newly-emerged adults) may take a week or more to solidify their adult color patterns and have female-ish coloration in the interim, and a chilly darner is a darker-colored darner.  Both males and females have prominent cerci (claspers) at the abdomen’s tip.  Common Green Darners have a characteristic bull’s-eye spot on their “forehead” that Comet Darners lack.  They can move each wing independently, which lets them hover, and even fly backwards.  They perch vertically, frequently in low vegetation, so they usually spot the BugLady long before she spots them.    

The long, slim, immature green darners (naiads) are found in still or very slowly-moving, shallow waters, preferably without sunfish and bass (nice set of naiad pictures here http://bugguide.net/node/view/238726/bgimage).  Adults frequent the air above those habitats but may be seen far from water.  

Two populations of common green darners – one migratory, the other resident – form tag teams in the air over Wisconsin.  Migrants from the south arrive early, often in late April, as their prey (small, aerial insects) start to appear.  They are the offspring, or the offspring’s offspring, of the darners that flew south in the fall (no, they apparently do not return to their natal ponds).  “Shivering” their wing muscles to heat up the thorax allows them to be active in cool weather, and they also bask in the sun.  This is so effective that temperatures as high as 110 degrees have been measured inside the thorax (which challenges the whole definition of cold-bloodedness).  The picture of the female with the battered wings was taken in early July, suggesting that she was a migratory female who was reaching the end of her trail. 

The migrants mate and die by early summer, leaving their eggs in the water, just as the naiads of the resident population emerge as adults, leaving their empty shells (exuviae) on shoreline vegetation.  These residents live a month or two as adults, depositing their eggs in late summer as the migrant adults emerge.  Resident naiads overwinter under the ice in a state of suspended animation called diapause and take 10 or 11 months to mature (possibly more, in the chilly waters “Up North”), while the migrant naiads need less than half that time in the warm waters of summer. 

Mating commences when a male clasps a female at the back of her head in mid-air (one source said that she can reject his advances), and then they retire to a perch to mate.  Females oviposit in the open, in woody and herbaceous plant material below the water’s surface, with the male typically retaining his grip on her head. 

The books say that these are the only darners that oviposit in tandem.  The books also say that a couple flying in tandem may be strafed by rival males.  The attendant male doesn’t have many options; he may flap his wings at the intruder, shake his abdomen, land in vegetation, and even bite his challenger.  According to Paulson, in Dragonflies and Damselflies of the East, females may curl their abdomen under and close their wings when under attack.  The BugLady once photographed (badly) an unattached male as he dive-bombed a second male whose abdomen was deeply submerged (presumably with an ovipositing female at the other end of it). 

The BugLady once found a female stuck in an especially dense and sticky, dragonfly-eating patch of blanket algae.  Did the female attempt to perch on the algae as she oviposited and get her wings stuck, only to be abandoned by her mate?  Or, alternatively, did she get thirsty and then get stuck?  Dragonflies “drink” by immersing their abdomen – water enters through the exoskeleton (the BugLady was able to fish her out with a stick). 

The naiads are active predators that will eat anything they can grab using their foldable “lower lip” (labium) – zooplankton, other aquatic insects (including dragonfly naiads), tadpoles, larval salamanders, and fish fry are all fair game.  In his wonderful write-up of the Common Green Darner, Kurt Mead (Dragonflies of the North Woods) muses that “If dragonfly larvae were eight to sixteen inches long, as they probably were 300 million years ago, we would dare not swim in fresh water for fear of being attacked” (read the whole account at http://www.mndragonfly.org/html/behavior.html) (there was a lot of oxygen in the atmosphere in those days, and some invertebrates grew to lunker size).  Despite their spiny exteriors and their ability to shoot forward by expelling a spurt of water forcefully from the rear of their abdomen, they are eaten by frogs, fish, and by other aquatic insects.  There’s even an “aquatic” parasitic wasp that lays its eggs in those of the green darner – Aprostocetus polynemae apparently walks down a twig or leaf stem into the water to find dragonfly eggs. 

Adults catch insects in the air and may eat them in mid-flight or on a perch.  They can also pick prey from a leaf or from the ground, and they’ve been known to stake out bee hives, to the distress of the bee-keeper.  At least one ambitious Common Green Darner killed a hummingbird, and this fact is mentioned in every darner write-up, though the BugLady suspects it’s pretty uncommon.  Adults are preyed on by robber flies, birds, spiders, and by other dragonflies; the people who monitor the fall raptor migration tell us that the southward movement of American Kestrels syncs with that of the darners, and that kestrel migration is fueled by darners. 

So, Common Green Darners migrate. Like birds, they respond to a suitable weather front – cold fronts for the southern flight and warm fronts for the far less conspicuous northern trip.  The journey south may take several weeks of stop-and-start flying (averaging 7 miles a day but capable of far more, depending on the wind), and they may be accompanied by black saddlebags and variegated meadowhawk dragonflies.  Late summer/fall migration is dramatic, huge swarms may take hours or days to pass a fixed point.  Bluffs on the west edge of Lake Michigan are great places to catch the show at eye level. 

The Common Green Darner is the State Insect of Washington – so much more exciting than Wisconsin’s honeybee (and you thought the state insect was the mosquito!).   

As always, don’t eat them – they carry parasites.  

Unfinished business – in response to the recent BOTW about deer flies, a few French scholars pointed out to the BugLady that she had misspelled the term “je ne sais quoi” as “jean es se qua.”  She had consulted Monsieur Google about the correct spelling, and she had, alas, believed him. 

Kate Redmond, The BugLady

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

Bug o’the Week – Golden Silk Orb Weaver – A Snowbird Special

Bug o’the Week
by Kate Redmond

Golden Silk Orb Weaver A Snowbird Special

Howdy BugFans,

It’s almost time for Snowbirds to head back north to rejoin us here in God’s Country for the final days/weeks/months of winter.  The BugLady read recently that the number of days below freezing in March here in God’s Country has drastically decreased in the past 25 years, and March is increasingly considered a spring month rather than a winter month (but when the BugLady was a kid……..).  The temperature may be moderating, but March still has plenty of tricks up her sleeve, and most of them involve snow.

BugFan Tom supplied the pictures of this big, beautiful spider that inhabits the South from Virginia to Texas (and beyond, to Argentina and Peru).  Thanks, Tom.


The brightly-patterned females may be more than two inches long with a five-inch leg span, (males are much smaller https://www.bugguide.net/node/view/76955/bgimage).  A spider this big (probably our largest orb weaver) that makes big webs necessarily gets noticed and collects lots of names, like Banana Spider, Golden Orb Weaver, Calico Spider, Golden Silk Spider, and Giant golden Orbweaver, and people who walk into the webs while hiking probably have other names for them.  MUCH has been written about their golden silk https://www.bugguide.net/node/view/566860/bgimage – more about that later.

The Golden silk orb weaver (Trichonephila clavipes) was formerly known as Nephila clavipes.  Nephila means “fond of spinning” and clavipes means “club-footed,” possibly a reference by Linnaeus to the dark tufts of hair on six of the female’s legs.  Recently, it and a dozen other genus members were moved to the genus Trichonephila – the Golden orb weavers.  Historically, GSOWs were the only member of that genus in North America, but in 2014, an East Asian species called the Joro spider found its way to Georgia, and it’s been spreading out through the Southeast https://www.bugguide.net/node/view/2490331/bgimage.   

Look for GSOWs in open areas in woods or edges, preferably near wetlands or coastal areas. 

Male GSOWs spin trap webs until they reach maturity, but then they set off to find a mate.  When they find a female’s web, they quietly move onto its periphery and feed on some of the prey she catches, and a female’s web may host a number of males.  Dewdrop spiders https://uwm.edu/field-station/bug-of-the-week/dewdrop-spider/ and Spiney-backed orb weavers https://uwm.edu/field-station/bug-of-the-week/bug-othe-week-spinybacked-orbweaver-a-spider-for-snowbirds/ also live on the web’s outskirts and share in the bounty.  An amorous male will approach the female while she is distracted by a meal, and he signals by vibrating both the web and his abdomen (he’s cautious, but there’s not a lot of sexual cannibalism in this species).  Males don’t produce much sperm, and they replace it slowly, so they favor newly-molted females who have not mated yet.  After he mates/attempts to mate, a male may move on to a new web. 

Females place two or more egg sacs, each containing a few hundred eggs, on surfaces near their web https://www.bugguide.net/node/view/914280/bgimage.  Hatching may be triggered by environmental cues in their damp habitats. The spiderlings stick together for about a week after hatching https://www.bugguide.net/node/view/917323/bgimage, and then they disperse.  By late summer, the tiny spiderlings of spring have reached full size and are making conspicuous webs.

This is a big spider that builds a big, strong web (up to six feet in diameter) that is capable of snagging some big prey, like moths, fast-flying horse flies, dragonflies (which are both GSOW eaters and eat-ees), butterflies https://www.bugguide.net/node/view/844364/bgimage, beetles (this one is June-beetle-size) https://www.bugguide.net/node/view/218713/bgimage, cicadas, and grasshoppers.  Though they trap both small and large prey, they prefer to eat the bigger insects. 

The webs are sturdy enough to capture birds.  Daniel M. Brooks, in an article titled “Birds Caught in Spider Webs: A Synthesis of Patterns” published in the Wilson Journal of Ornithology (2012), wrote that a review of international literature and list servers found 69 accounts of birds trapped in webs.  Nephila species, especially GSOWs, accounted for half of the reports of mostly hummingbird-sized birds (though a small dove was reported, and the author personally observed a Swainson’s thrush tangled in a web), and while some were able to free themselves, a significant number had been killed and wrapped by the spider.

The asymmetrical, orb-type web is usually located between two and eight feet off the ground (but may be at treetop height).  When prey is abundant, GSOWs may cache as many as 15 wrapped insects in a “barrier web” – a debris-strewn area along one side that serves to warn/block predators and help keep the web clean.  One source said that the organic waste held in the barrier web may attract insect prey by its odor. 

GSOWs’ main predators are wasps that collect them to provision their egg chambers, and birds. 

Unlike many species of orb weavers that replace their webs daily, eating the old web to harvest its protein, GSOWs repair damaged webs.  Researchers believe that the yellow tint, the intensity of which the spiders can control, may attract bees, and it may also help to camouflage a web in the shade.  A number of females may make webs close to each other https://www.bugguide.net/node/view/826303/bgimage.

This is some serious silk!!!  Nephila/Trichonephila silk has a high thermal conductivity, is stronger, by weight, than steel (it’s being studied with hopes of replicating its extreme strength), and it has some interesting medical applications.  Wikipedia reports that it may be beneficial in surgeries involving the nervous system because it may guide and encourage neuronal regeneration. 

Wikipedia also reports that hunters in New Guinea make fishing nets from the silk.

Finally, enterprising folks have experimented with it as a textile, creating garments (thanks to the labors of millions of spiders) https://en.wikipedia.org/wiki/Golden_Spider_Silk_Cape. 

FUN FACT ABOUT SPIDERS: the tips of the legs of spiders that wander around and don’t make trap webs point outwards, and the tips of the legs of trap-web-spinners point inwards.

FUN FACT ABOUT NEPHILA/TRICHONEPHILA SPIDERS: The genus Nephila is not only the oldest-known surviving spider genus (165 million years), but it includes the largest-known fossil spider.

Kate Redmond, The BugLady

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

Bug o’the Week – Tumbling Flower Beetle

Bug o’the Week
by Kate Redmond

Tumbling Flower Beetle

Howdy, BugFans,

Way back in 2010, when the BugLady wrote an episode called “Big Beetle – Tiny Beetle,” the tiny beetle was a generic Tumbling flower beetle.  There are a whole bunch of (unrelated) beetles that share the common name “flower beetle” – hermit, bumble, shining, soft-winged, and more, along with the long-horned flower beetles.  Tumbling flower beetles are interesting little critters, so here’s an enhanced biography – new words, new pictures.


The psychological principle called “The Law of Closure” explains that when we see text with partial or misspelled words, our brains tend to serve up the missing information, often without our even noticing its absence (which is why over-familiarity with a text makes for bad proof-reading).  The incomplete becomes complete.  That being said, the BugLady must confess that whenever she sees the name of the Tumbling flower beetle family – Mordellidae – her brain always fills in the name of a kind of lunch meat, Mortadella.  BugFans may come to their own conclusions/diagnoses about that. 

Tumbling flower beetles, so-called because of their method of locomotion, are also called Pintail beetles, because of their pointy anatomy.  There are more than 2,000 species of Tumbling flower beetles distributed over six continents, with 200-plus species in North America, and 68 of those in Wisconsin.  They seem to be in continuous taxonomic limbo – there’s been a lot of shuffling and more is expected to happen.  They can be a very confusing bunch – to tell the difference between some of the species, you have to count the ridges on the hind tibia and tarsus (leg and foot). All of the species in North America belong in the same subfamily (Mordellinae), and speaking of names, there are some very fine genus names like Mordellistena (the largest genus), Hoshihananomia, and Yakuhananomia.   

These small (about ¼”), active, caraway-seed-shaped beetles always remind the BugLady of a flea on a flower.  Tumbling flower beetles are wedge-shaped (tapered toward their pointy rears), and are covered with short hairs that are silky and slippery and that may give them an iridescent shine.  They have long, flattened, hind legs (the better to tumble with, my dear) and hump-backed bodies, with heads angled down almost under the first segment of the thorax (sort of a “pre-somersault” position).  Their elytra (wing covers) are shorter than their abdomen. 

Tumbling flower beetles are generally dark, but some are more decorative https://www.bugguide.net/node/view/815486/bgimage https://www.bugguide.net/node/view/927768/bgpage https://www.bugguide.net/node/view/1629463/bgpage https://www.bugguide.net/node/view/815525/bgimage https://www.bugguide.net/node/view/958803/bgimage https://www.bugguide.net/node/view/1277258/bgpage

In an article in the journal PSYCHE (1987) Deyrup and Eisner write that “The Mordellidae are small, wedge-shaped beetles commonly found in one of the most dangerous of all insect habitats, the open inflorescences of plants.”Food and habitat-wise, Tumbling flower beetles tend to be generalists.  Adults feed on nectar and pollen (their hairy bodies make them effective pollinators), and some nibble on the flowers a bit.  

The larvae, concealed within plant stems https://www.bugguide.net/node/view/2083164/bgimage, leaves, galls, dead trees, or shelf fungi, feed on dead wood, the pith of herbaceous plants, and woody fungi, and larvae of a few species may be predaceous. Most sources agreed that although they like sunflowers, the larvae aren’t considered an agricultural pest.  Downy Woodpeckers find the larvae in plant stems, and crab spiders capture adults on flower heads.

Do they tumble?  Oh my, yes!  When alarmed, which seems to be often, they bail, letting go of the flower and tumbling or jumping off.  Part way down, they may spread their wings and fly (they are good flyers) or they may fall all the way to the ground, where they are impossible to find.  They jump by pushing off into a spiraling somersault using one of their extra-long back legs, and they rotate clockwise or counterclockwise in the air, depending on which leg they pushed off on.  Sources say that these gymnastics help the beetle position itself for flight. 

Deyrup and Eisner again: “Their chief protection against the many predators that frequent flowers is a series of convulsive leaps followed by rapid flight, as acknowledged in their common name, “the tumbling flower beetles.” Their escape from a predator’s grasp is facilitated by their wedge shape and covering of smooth, backward-pointing hairs, while their movement and purchase among stamens and floral hairs may be assisted by rows of tibial and tarsal setae strongly reminiscent of the combs of fleas. These escape mechanisms, while undoubtedly effective against many predators (including entomologists), have the disadvantage that they involve abandonment of the feeding site.”

Adults emerge in late spring, romance ensues, and females lay eggs in decaying wood or in living plant tissue (there may be as many as 40 larvae in a single sunflower).  Tumbling flower beetles often find themselves in the company of other Tumbling flower beetles and are said to be aggressive toward them.  They overwinter as larvae in their food plant, and there’s only one generation per year. 

An article about Tumbling flower beetles on the Beyond Pesticides website states that “the tumbling flower beetle’s ancestors were some of the earliest insects to utilize flowers for food and habitat. In doing so, these ancient pollinators began an important collaboration between flowers and beetles which continues today.”has mated and less interested in a territory where he’s been beaten by a rival.

Kate Redmond, The BugLady

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

Bug o’the Week – Bugs in the News XVI

Bug o’the Week
by Kate Redmond

Bugs in the News XVI

Greetings, BugFans,

Let’s take some time off from the relentless, 24-hour news cycle and enjoy a few bug stories.


MOSQUITOES – The BugLady always snickers at the obligatory TV news spot in mid-spring in which someone earnestly tries to predict what kind of mosquito season is on the horizon (“Well, Pete, if we get a lot of rain, we could have a lot of mosquitoes this year…”).  Whatever the summer brings, how do mosquitoes find you, and do they find you delectable?    https://www.smithsonianmag.com/science-nature/why-do-mosquitoes-bite-some-people-more-than-others-your-blood-type-sweat-contents-even-alcohol-consumption-may-make-you-more-attractive-pesky-insects-10255934/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=editorial&lctg=91269370. 

(The BugLady also snickers at the weather folks who report that visibility is limited to only five miles or two miles instead of ten.  Most people don’t live where they can actually see five miles, and most of us aren’t flying an airplane.  All we need is enough visibility – maybe a quarter mile in each direction – to be able to pull through an intersection safely.  But that’s a different soapbox).

INSECT SPECIES – There are about 100,000 species of insects in the US, and almost one-fifth of those species can be found in Wisconsin!  Most live out their whole lives without producing a single blip on our collective radars, and formal insect surveys are a recent phenomenon, so it’s hard to say what the population trends are for many species.  https://news.cals.wisc.edu/2002/06/03/study-reveals-how-little-we-know-about-wisconsins-insect-diversity/

SPIDERS: – Spiders would appreciate a little peace and quiet https://www.smithsonianmag.com/smart-news/getting-annoyed-at-your-noisy-neighbor-spiders-are-too-new-research-finds-theyll-build-webs-differently-in-loud-conditions-180986296/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=editorial&lctg=91269370

LADY GAGA TREEHOPPER – Ever wonder how newly described insects get their names https://www.smithsonianmag.com/smart-news/insect-wacky-fashion-sense-named-after-lady-gaga-180974435/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=20200317-daily-responsive&spMailingID=42045395&spUserID=ODg4Mzc3MzY0MTUyS0&spJobID=1721617709&spReportId=MTcyMTYxNzcwOQS2?

WALKING STICK – Our Northern walking sticks max out at about 3” long (counting their antennae, maybe 5”) (and what cute nymphs they have https://www.bugguide.net/node/view/1253217/bgimage).  They’re dwarfed by this newly-discovered Australian stick insect https://www.smithsonianmag.com/smart-news/gigantic-stick-insect-discovered-in-australia-might-be-the-continents-heaviest-insect-180987108/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=editorial&lctg=91269370.

BUMBLE BEES – Turns out that extreme heat can have an unexpected impact on bumble bees https://www.smithsonianmag.com/smart-news/heat-waves-can-make-bumblebees-lose-their-sense-of-smell-study-finds-heres-why-thats-a-problem-180985119/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=editorial&spMailingID=50214690&spUserID=ODg4Mzc3MzY0MTUyS0&spJobID=2782791375&spReportId=Mjc4Mjc5MTM3NQS2.

EXTRAFLORAL NECTARIES – Some insects protect the plants they live on, and the plants reward them for it https://www.smithsonianmag.com/blogs/smithsonian-tropical-research-institute/2025/07/28/mutualism-under-pressure-new-research-in-panama-shows-a-plants-ability-to-keep-its-defender-ants-happy/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=editorial&lctg=91269370.  BOTW explored EFNs a while back https://uwm.edu/field-station/bug-of-the-week/ants-in-my-plants-rerun/   

INVASIVE SPECIES ALERT – be on the lookout for a new alien species, the Elm zigzag sawfly – https://www.smithsonianmag.com/smart-news/this-invasive-wasp-is-wreaking-havoc-on-elms-in-north-america-and-the-damage-may-soon-spread-to-other-trees-180987991/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=editorial&lctg=91269370.  Here’s some info from the Wisconsin DNR https://forestrynews.blogs.govdelivery.com/2024/08/15/new-invasive-pest-discovered-in-wisconsin/.

The BugLady saw a fly sitting on the outside of her cottage the other morning. 

The BugLadye routes between those places.  A male will be more faithful to a territory where he has mated and less interested in a territory where he’s been beaten by a rival.

Kate Redmond, The BugLady

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

Bug o’the Week – Eastern Amberwing Redux

Bug o’the Week
by Kate Redmond

Eastern Amberwing Redux

Salutations, BugFans,

2026 – When the BugLady wrote this episode in February of 2013, she kicked it off by griping about the weather – a favorite, February, indoor sport.  This year, we’ve had many days of below average, below freezing, and below zero temperatures.  How cold is it?  Three weeks ago, one of her water pipes froze and burst, and when she tossed the sodden beach towels out the door into the yard, they froze instantly.  They’re still stuck solidly to the ground.

This rerun contains a few new words (because who can look at a 13-year-old manuscript and not tweak it?), but all new pictures, because the Eastern Amberwing is a wondrous creature to photograph, even when it’s hovering just out of range.

2013 – The weatherman keeps saying “Mixed precipitation” and it’s making the BugLady plenty crabby, so she’s going to think about dragonflies, instead.  Here’s a little bit of sunshine on the wing.

Several BugFans have asked the BugLady how she selects the stars of BOTW.  First, she needs a decent picture to spin the tale around, and Eastern Amberwings have posed prettily (some of them).  This tiny dragonfly has some interesting stories to tell.

At a hair under an inch in length, the Eastern Amberwing (Perithemis tenera) is the second smallest dragonfly in Wisconsin (the very-uncommon Elfin Skimmer is a bit smaller and is not yellow).  Some damselflies, like this Spreadwing https://www.bugguide.net/node/view/39074, are longer than Amberwings, but damselflies are slim and dragonflies are bulky.  Their flashy wings make them look bigger than an inch to the BugLady.  The male EA’s wings are pure gold; the female’s wings are brown-spotted on a sometimes-amber background (she resembles a tiny Halloween Pennant, of previous BOTW fame).  Males and females have yellowish legs and have rings around the segments of their abdomens.  The abdomens of both are thick (the female’s looks especially swollen). 

Because of their coloring, their rapid, erratic flight, and the way they twitch their wings and abdomens when at rest, EAs are considered wasp mimics.  Their wasp “disguise” may save them from aerial and terrestrial predators, but the BugLady found a website instructing fly fishermen on how to tie an EA fly, so apparently fish are willing to take a chance.

Where do you find them?  Over most of the US, east of the Great Plains and south into Mexico.  Here in God’s Country, they fly in mid-summer, but they grace the landscape year-round in the southernmost parts of their range.  Look for them near quiet or very slowly-moving waters (the BugLady often sees them in the bays and inlets along the shore of the Milwaukee River).  Look for them, too, far from water, hunting at grass-top-height over weedy fields or perched on vegetation at a woodland’s edge. 

Where do you find them, entomologically speaking?  In the order Odonata (the dragonflies and damselflies) and in the family Libellulidae (the Skimmers).  Perithemis apparently is a reference to Themis, a figure in Greek mythology, and a number of other Skimmer genera incorporate Themis’s name.  According to Berger and Hanson in Dragonflies, tenera is Latin for “tender,” “delicate,” or “soft” and implies youth (a dragonfly is called a teneral during the first few days of adult life).

They are “perchers,” and unlike most dragonflies, may be seen sitting on flowers (they are not considered pollinators, despite the picture caption in one photo site).  On hot, summer days, they may lower their wings to shade their thorax and point their abdomens skyward to reduce direct contact by the sun’s rays.  Eastern Amberwings find food by patrolling or by perching and watching; they catch insects in flight, but they generally perch to eat them.  Females often raise their abdomens while in flight. 

The aquatic young (naiads) eat tiny fellow-aquatic invertebrates, and unlike the more specialized naiads of other dragonflies, they use all parts of their habitat, hunting at any depth in their pond’s water column.  For their carnivorous ways, Eastern Amberwings and other dragonflies are given a thumbs-up by a Florida pest control service, which says, “From the tiny Eastern Amberwing, to the flamboyant Halloween Pennant, dragonflies are some of the most important and charismatic beneficial bugs. They’re indiscriminate predators of many pest insects, including mosquitoes, flies, ants and wasps…… Next time you see one zip across your yard, consider saying thanks to the dragonfly for helping to control the pest population.”   

Eastern Amberwings sure know how to court a gal.  A male flies low over the water, patrolling a territory of choice egg-laying turf (weedy aquatic sites) about 20 feet wide and defending it vigorously – darting out at intruders and displaying with those spectacular wings.  When a female approaches, he follows and courts her, swaying back and forth, abdomen raised.  If she’s agreeable, she follows him home.  He hovers over his territory while she evaluates it, and if she likes it, she gets him along with it.  After mating, she lays eggs – usually alone, but sometimes under his watchful eye.  The blob that she releases from the tip of her abdomen explodes as it enters the water, releasing as many as 150 eggs over the water’s surface.  In his zeal to protect his “investment,” the male sometimes grabs an intruding male and flies in tandem with him, keeping him away from the female. 

It’s not surprising that a critter that’s as flashy, as unmistakable, as widely distributed, and that has so many interesting behaviors has attracted the scientific community.  A number of different studies have demonstrated, at least, that Eastern Amberwings have attitude.  Here are some of the things that have been discovered about them:

  • Site fidelity – Once a male finds what he thinks is a high-quality spot to lay eggs (an oviposition site), he protects it by day (he leaves at night to roost in a tree).  He will defend it for days, especially if he has mated there.  If he deliberately changes territories, he “moves up” to a higher quality site.  He can be evicted from his territory by a feistier male. 
  • Heterospecific pursuit – Besides chasing each other, male Eastern Amberwings chase after any flying insect that could be mistaken for another Eastern Amberwing (that’s heterospecific pursuit).  They’ve been observed pursuing large horse flies and small skipper butterflies, but they ignore larger dragonflies.  Researchers concluded that following a horsefly was simply a case of mistaken identity of a similar-sized insect, but there may be something about the skipper’s coloration that pushed the Eastern Amberwings’ buttons.  
  • The cost of doing business – Defending a territory is “expensive,” and the more “close neighbors” an Eastern Amberwing has, the costlier it is for him.  Having more neighbors results in more intrusions.  More intrusions mean more energy spent chasing intruders or simply darting around being territorial.  Expensive? Yes, but non-territorial males rarely get to pass on their genetic material. 
  • Home field advantage – Unlike those of some other Skimmers, Eastern Amberwing’s territorial disputes may escalate, but they are non-contact sports.  If the aggression does not build, the territory-holder tends to win, but if the conflict escalates, victory often goes to the younger Eastern Amberwing.  Males who had fewer interactions overall tended to have more energy and win low-key conflicts.  The territory-holder may win other face-offs because he psyches out the competition or because the intruder decides he doesn’t like the territory enough to fight for it. 

Spatial learning – Dragonflies can remember the locations within their habitat where they find food, breed, and roost, and they know the routes between those places.  A male will be more faithful to a territory where he has mated and less interested in a territory where he’s been beaten by a rival.

Kate Redmond, The BugLady

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

Bug o’the Week – Long-jawed Pedunculate Ground Beetle

Bug o’the Week
by Kate Redmond

Long-jawed Pedunculate Ground Beetle

 Greetings, BugFans,

BugFan Dave shared these spectacular pictures of a very cool beetle that he found last summer – a ground beetle in the family Carabidae, a huge family with 40,000+ species.  It’s in the subfamily Scaritinae, the “Pedunculate ground beetles,” so-named for the constriction – peduncle – between the wider thorax and abdomen.  The wonderful “MOBugs” blogspot (“Missouri’s Majority”) suggests that they should be called “Scary pincher ground beetles.”  It’s in the genus Scarites (skar-EYE-tees), a genus that numbers about 190 species worldwide with seven or eight (or nine) species in North America, most of them with very small, very southern ranges.

More about the ID of this beetle in a sec.

SCARITES – THE GENUS

Scarites beetles are often found under loose rocks and bark, boards, mulch, leaf litter, and debris, on forest floors, on or burrowing into moist, sandy soil, in gardens, in residential areas, and at the edge of agricultural fields.  They’re common, though, alas, the BugLady’s never seen one – she needs to turn over more logs.  Their mandibles and general air of invincibility cause some people to mistake them for stag beetles https://www.bugguide.net/node/view/1209374, which are in a different family.

They are shiny and black, with spiky legs and an armored-looking head.  The elytra (hard wing covers) are ridged/grooved, and a couple of “creases” on the shield that covers the thorax form a “T.”  Males tend to be larger and “toothier” than females, with a slightly more bulging head.  Some sources describe the larvae as looking like “fast-moving millipedes with large jaws” https://www.bugguide.net/node/view/2485075/bgimage.

Like many ground beetles, they are fierce and speedy predators that shelter during the day and hunt at night.  Pedunculate ground beetles – La mère, le père et les enfants – eat a variety of surface and soil-dwelling invertebrates like earthworms, slugs and snails, caterpillars, maggots, ants, etc.  It’s also reported that they eat insect eggs and that they scavenge on dead insects, including dead Scarites, and that they may eat some plant material.  They’re considered beneficial around gardens and agricultural fields, though they don’t discriminate between pest and non-pest prey.  At an inch-or-so long, they’re big enough so that researchers have attached transmitters to their abdomens to track their activities in agricultural fields!  Some ground-foraging songbirds eat them. 

In fact, several Extension publications offered tips about attracting Scarites beetles to your garden, creating a refuge by leaving a portion of lawn bare and/or un-mowed and/or brushy (all of which benefits solitary wasps, too), and, as always, by limiting/eliminating pesticides.

The BugLady couldn’t find much about their biographies other than the fact they overwinter as both larvae or adults, and the fact that when they’re alarmed, they will fall over, pull in their antennae and legs, stiffen, and play dead.  One blogger reported a strange, but not unpleasant odor when he handled a “dead” one.  The mandibles appear to be Defense Option B.  

There’s a video of a Scarites beetle on the “All Bugs Go to Kevin” blog https://www.facebook.com/groups/AllBugsGoToKevin/posts/659539831568469/, and one of a larva at the original Bug of the Week site https://bugoftheweek.com/blog/2020/10/12/an-unusual-but-not-unpleasant-home-invasion-by-a-beneficial-beetle-big-headed-ground-beetle-scarites-subterraneus, where Professor Raup reports seeing them in his garden, “On several occasions I have seen Scarites larvae dashing across patios and walkways as they move from one planting bed to the next.”  

So – which Scarites is this?

THE LONG-JAWED PEDUNCULATE GROUND BEETLE (Probably)

The two most common, most widely-distributed genus members in North America are the Big-headed/Pedunculate ground beetle (Scarites subterraneus) https://www.bugguide.net/node/view/906988 and Scarites vicinus https://www.bugguide.net/node/view/919285/bgpage, which most sources said has no common name but that one source called the Long-jawed pedunculate ground beetle.  The two are tough to tell apart, even by experts.  The BugLady is going to take her usual taxonomic leap and say that this is Scarites vicinus, based on her reading of the shape of the  three antennal segments (antennomeres) – slightly elongated vs round https://www.bugguide.net/node/view/163900.  Scarites vicinus is also larger than Scarites subterraneus, with a broader head, and the shield on the thorax is “rounder.” All of which can be somewhat subjective – the eye of the beholder.  There’s more information available about the Big-headed ground beetle than there is about the Long-jawed pedunculate ground beetle. 

They’re found in a few mid-Atlantic states, a couple of Gulf states, and some Great Lakes states – and South Dakota.

Thanks, Dave.   

Kate Redmond, The BugLady

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

Bug o’the Week – Bee Moth

Bug o’the Week
by Kate Redmond

Bee Moth

Greetings, BugFans,

BugFan Danielle sent these shots and wondered if the moth might be a Bee moth (Aphomia sociella) (the Bee moth is not to be mistaken for the amazing little Moth fly, of previous BOTW fame – https://www.bugguide.net/node/view/1352263).  The BugLady agreed that it could very well be, but she emphasized that if there is a secret handshake for moth identification, she hasn’t learned it yet.

Bee moths are in the family Pyralidae, the Grass or Snout moths (the family Crambidae shares the name “Snout moths,” and for the same reason – because the sensory mouthparts (labial palps) of some members are prominent and protruding https://www.bugguide.net/node/view/1788429/bgpage).  This is the BugLady’s favorite Pyralid moth https://www.bugguide.net/node/view/2498157/bgimage.

Pyralids are mostly small, drab moths, some of which, like the Bee moth, take a toll on economically important plants or pollinators, some of which control unwanted plants, some of which are bred commercially as pet foods and bait, and many of which simply live out their lives under our radar.  Pyralid moths may hold their wings flat at rest or may roll them (https://www.bugguide.net/node/view/2438633/bgimage) or may hold them out to the sides.  They have tymbals (hearing organs), presumably so they can detect bats’ echolocation signals and dodge them.  Their larvae live concealed lives in stems, fruits, or seeds, within tied leaf shelters, in the soil, or in nests of bees and wasps and sometimes mice. 

BEE MOTHS, also called Bumble bee wax moths, aren’t from around here.  They were first reported in North America in 1864, and like the BugLady’s ancestors, they came over on the boat from Europe.  They’re found in the northeastern quadrant of North America from Tennessee, north (plus Mississippi), and in a few western states and British Columbia. 

Their wingspan is listed as about 0.70 to 1.50 inches, which is quite a range in a species this size, especially since females are not much larger than males.  They may be tan, reddish https://www.bugguide.net/node/view/1665136/bgimage, or greenish https://www.bugguide.net/node/view/2370594.  Males are more intensely-colored and patterned, and females have a dark spot in the middle of each fore (top) wing.  They seem to have a little iridescence going on.

Courtship is complicated, involving wing-fanning and the deployment of pheromones by both females and males (whose scents may also repel competitors, but if that doesn’t work, fisticuffs may ensue).  Males also produce ultrasonic sounds (songs).  One source suggested that the pheromones are biosynthesized from the Aspergillus fungus eaten by the larvae in nests and hives.  Using her sense of smell, a female locates exposed, above-ground nests of some social bees and wasps like honey bees, bumble bees, German yellowjackets, and bald-faced hornets and lays as many as 100 eggs there.  She arrives in early summer, before the hive/nest population peaks and the hosts’ defenses strengthen. 

Several sources labeled the small, yellow larvae as “inquilines,” feeding on the nest detritus, waste, dead bodies, pollen and honey, wax, and fungus from within a tough tent of silk.  But they’re not just harmless guests – they cross the line by damaging the nest structure with their tunneling and later with their dense webs and galleries https://nurturing-nature.co.uk/wildlife-garden-videos/waxmoth-larvae-safe-behind-their-tough-silken-blanket-video/, and as they get older, by eating the eggs, larvae, and pupae of their hosts (unusual because most moth larvae are vegetarians).  In some cases, the larvae may end up relegated to a small section of a nest as it expands.  They exit the nest in fall, overwinter as larvae, and pupate in spring.  They are not welcome in commercial bee operations, and they seem more able to get a foothold in honey bee hives that are already compromised.  

The feeding tent may protect larvae in case their hosts discover them; adult moths play possum when alarmed, which may serve them both outside and inside the host’s nest.

Sources danced around the severity of the impact that Bee moths might have on honey bees.  They’re obviously a potential problem in commercial bee operations, but they’re not listed among the major offenders – various mites and lice and the larvae of another alien Pyralid called the Wax moth – and the internet didn’t light up with Bee moth Wanted posters.  A blog from Yorkshire, England stated that “They are not a pest of honey bees.”  An interesting point was made in one research paper about the connection between nearby commercial honey bee operations and the health of wild bumble bee nests.  Researchers noted that competition with honey bees – sharing food resources – stresses bumble bees, and that having honey bees as close neighbors increases the risk of transferring disease organisms and parasites (like Bee moths) from honey bee hives to bumble bee nests, where their impact may be greater.  

Thanks, Danielle! multiple generations in the south, where the final generation of caterpillars overwinters.  They form a cocoon in spring.

Kate Redmond, The BugLady

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

Bug o’the Week – Giant Leopard Moth

Bug o’the Week
by Kate Redmond

Giant Leopard Moth

Howdy, BugFans,

Honorary BugFan Lisa sent the BugLady a picture of her glove posed next to a big, fat caterpillar and asked if it might be a wooly bear.  There are a number of species of caterpillars that are called wooly bears, but the wooly bear in question is the caterpillar of the Isabella Tiger Moth, a caterpillar that has found a place in folklore for its (supposed) ability to predict winter weather https://uwm.edu/field-station/bug-of-the-week/wooly-bear-caterpillar-again/.  When a wooly bear has wide, black bands, it’s predicting a harsh winter.  Mistaking this black caterpillar for a wooly bear that’s gone all in for an Armageddon winter is a common mistake

Turns out that the caterpillar was something less common and way more exciting, and coincidentally, the BugLady had found a similar caterpillar in the same area earlier in fall.  She’s seen one adult – tucked up under the eaves in Ohio, and would love to find another.

GIANT/GREAT LEOPARD MOTHS, aka Eyed Tiger Moths (Hypercompe scribonia) (also called “fever worms” in Missouri) are in the family Erebidae – Erebidae comes from the Greek Erebus, which means “from the darkness.”  The family was created from parts of several other moth families, and it includes the Tiger https://www.bugguide.net/node/view/1548841/bgpage,

Lichen https://www.bugguide.net/node/view/2144967/bgimage,

Tussock https://www.bugguide.net/node/view/987864/bgpage, and

Underwing moths https://www.bugguide.net/node/view/2284502/bgimage, among others, whose subfamilies and tribes have some pretty spiffy members.

Look for Giant Leopard Moths in grasslands and along woodland edges from the Great Plains to the Atlantic and from far southern Ontario through Texas to South America.  They are widespread but are not considered common within their range.

This is one spectacular moth!  Some individuals are more “dotted” https://www.bugguide.net/node/view/1852552/bgimage than “eyed” https://www.bugguide.net/node/view/2265267/bgimage, and those beautiful, black and white wings hide a colorful body https://www.bugguide.net/node/view/977160/bgimage.  And then there are the blue spots (more prominent in some individuals than in others) (and again – how does iridescence benefit a nocturnal species?) https://www.bugguide.net/node/view/1967173/bgimage!  And they’re sizeable moths https://www.bugguide.net/node/view/2254472/bgimage, with a wingspread exceeding three inches (females are a bit larger than males https://www.bugguide.net/node/view/1388256/bgimage).  There are six other members in the genus Hypercompe in North America, mostly western or Texan, and they all have a similar gestalt.   

Ohio blogger Jim McCormac notes that, counterintuitively, this brilliant moth can be difficult to see on a tree trunk, its shape broken up by the pattern of dots and eyes.  It has been theorized that the bold, black and white wings may be a kind of aposematic (warning) coloration because the moths do have a chemical defense – when alarmed, they exude drops of bad-tasting, yellow liquid from their thorax https://www.bugguide.net/node/view/1586453/bgimage.  The moths will flip their wings up and display their technicolor body, possibly a behavioral defense to scare predators.  Apparently, no one knows if they’re palatable to birds, and the BugLady didn’t find any accounts of enterprising scientists who admitted to tasting one (don’t laugh, someone tried a Viceroy butterfly) (not toxic like its Monarch look-a-like, but bitter because the caterpillar eats willow leaves).

Older caterpillars, which may grow to three inches long, have red spiracles (breathing pores) in a line along their sides, and red bands between the segments https://www.bugguide.net/node/view/58331.  The BugLady once used the metaphor of a demure woman whose undergarments are red, but she may well have borrowed that phrase from somewhere.  Some fuzzy caterpillars have irritating hairs, but not Giant Leopard Moths. 

Adults mate, a process that may take as long as a day and include walking from sunny to shady spots as needed.  Eggs are laid on one of the species’ many host plants, which include some woody plants (maples, willows, cherries, and mulberries), but mostly a variety of low-growing, bitter, herbaceous plants like dandelions, broad-leaved plantain, violets, and, surprisingly, broccoli and cabbage.  Caterpillars are nocturnal eaters that hide under leaf litter or tree bark during the day.  Adults do not feed.

They overwinter as caterpillars, often under the bark of decaying trees, fortified by a natural glycerol antifreeze.  Jim Sogaard, in Moths and Caterpillars of the North Woods (a great little book that’s currently out-of-print, so snap one up if you find one) writes that “Caterpillars can survive temperatures of 26.6 degrees F. with 45% of their body water frozen to ice but perish when temperatures reach 14 degrees F.”  Like the wooly bear, caterpillars may rouse during mid-winter thaws and take a hike, only to tuck themselves in again when winter returns.  There’s one generation per year in the north and multiple generations in the south, where the final generation of caterpillars overwinters.  They form a cocoon in spring.

Kate Redmond, The BugLady

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

Bug o’the Week – Eastern Parson Spider

Bug o’the Week
by Kate Redmond

Eastern Parson Spider

Howdy, BugFans,

One of the BugLady’s inquilines is an Eastern parson spider.  An inquiline (from the Latin inquilinus meaning “lodger” or “tenant”) is an animal that lives in the dwelling of another animal.  Like the Tree frog that overwintered with the BugLady last year, the Parson spider is finding enough to eat.

Some definitions of inquiline allow for the possibility that the “roomer” might morph into an eater or an eat-ee of the host, but that would nudge it into a different ecological category.  The relationship of the host to its inquiline guest is defined as a “commensal” one – positive for the guest; neutral for the host(ess).

Eastern parson spiders (Herpyllus ecclesiasticus) (great scientific name!) get their name from the white markings on the top of the abdomen that are reminiscent of the white cravats of 19th century preachers.  They’re in the ground spider family Gnaphosidae.  There are a dozen species in the genus Herpyllus in North America, and most can’t be identified to species with photos.  The Western parson spider (H. propinquus – another great name) (the BugLady’s Dad used to introduce juicy vocabulary words when she was a kid, and “propinquity” was one of them, along with “prestidigitation,” “prevarication,” and, of course, “procrastination”) is nearly identical to the Eastern parson spider, mostly separated by range.  Eastern parson spiders occur mainly east of the Rockies, from Canada into Mexico.   

These small, hairy spiders live on the ground under rocks, logs, and other forest debris, and on tree trunks, but it’s not uncommon for them to get into mailboxes, where they might be collected with the day’s mail, or to come indoors in fall, where adults may overwinter (they don’t breed indoors).  

Females are about 3/8” long, and males are about ¼”, and they are speedy spiders that often run in a zigzag line, so the BugLady photographed her spider at the bottom of her “Invertebrate-Catch-and-Release Jar,” a repurposed parmesan cheese shaker.  Contributors to bugguide.net have done better – here’s a good shot https://bugguide.net/node/view/1399774/bgimage and a glamour shot https://bugguide.net/node/view/1635888/bgimage.  

Eastern parson spiders don’t spin trap webs, they’re active, nocturnal/crepuscular hunters that search for their prey – small invertebrates, including other spiders – on foot.  This one has subdued a moth that was bigger than it was https://bugguide.net/node/view/1002561/bgimage.  They do use silk for other purposes – they rest in silk retreats under boards, bark, rocks, etc. in the daytime, young spiders that stay outside during winter make a silk cocoon under loose tree bark, and females enclose their eggs in a silken sac in summer before hiding it (and they stay around to protect it).  Not a lot is known about their natural history, but the fact that adult parson spiders can be found in any season suggests that they may have a two-year life cycle.   

Along with the usual “Scare sites” that pop up when you Google animals (“Eastern parson spider bite”/“Eastern parson spider poisonous”), there’s some discussion about whether the Parson spider’s bite is problematic for humans, beyond the rare individual who might be allergic.  The conclusion seems to be that the bite is painful and may produce some temporary inflammation, but it’s not a medical emergency, and the odds are good that you’ll never be bitten by one because spiders would rather flee than fight.  As one author points out, spider bites are very rare occurrences and misinformation is rampant. 

Kate Redmond, The BugLady

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

Bug o’the Week – Tri-colored Harp Ground Beetle

Bug o’the Week
by Kate Redmond

Tri-colored Harp Ground Beetle

Howdy, BugFans,

What an awesome beetle – thanks to BugFan Dave for sharing it!

There’s not a whole lot of information out there about this species, and there’s some misinformation (more about that in a sec), so let’s sneak up on it, taxonomically.  Tri-colored harp ground beetles are in the Ground beetle family Carabidae, a huge (34,000 species), cosmopolitan (found ‘round the world) family of often metallic or dark and shiny, mostly nocturnal (except for the wonderful, diurnal Tiger beetles and a few others), carnivorous beetles whose eggs, larvae, and adults tend to live under debris or in crevices on/near the ground.  (The BugLady wouldn’t want to diagram that sentence).  Most insects have a one-year life span and spend more than three-quarters of it in the larval, nymphal, or naiad stage, but Ground beetles may live two or three years as adults.

Tri-colored harp ground beetles are in the subfamily Harpalinae, the Harp ground beetles, which, with about 6,400 species worldwide (1,230 in North America) is the largest subfamily of Ground beetles.  Lots of species, lots of variety, and lots of lifestyles, and some species are considered biological controls for nuisance insects.  Like other Ground beetles, Harp ground beetles defend themselves chemically with noxious or odorous secretions from pygidial glands located toward the rear of the abdomen.  According to Wikipedia, the members of another Carabid subfamily, the Anthini, “can mechanically squirt their defensive secretions for considerable distances and are able to aim with a startling degree of accuracy; in Afrikaans, they are known as oogpisters (“eye-pissers).“

Members of the genus Chlaenius are called “Vivid Metallic Ground Beetles” “chlaeri” comes from a Greek word for “cloak” and refers to the pubescence (fine hairs) on the dorsal side of the elytra (wing covers) – the pubescence that may wear off as the beetle moves through its world.   Here are some close relatives: https://bugguide.net/node/view/1516694/bgimage, https://bugguide.net/node/view/2506203/bgimage, https://bugguide.net/node/view/2044112/bgimage, https://bugguide.net/node/view/891445/bgimage. A really, big Chlaenius beetle would approach an inch in length. 

TRI-COLORED HARP GROUND BEETLES (Chlaenius tricolor) aka Yellow and Green Harp Ground Beetles, are divided into two subspecies.  One (Chlaenius tricolor tricolor) is found east of the Rockies from Canada south to Georgia, and the other one (Chlaenius tricolor vigilans) lives west of the Rockies from Canada to Guatemala.  They’re found under leaf litter or logs in damp areas and shores of rivers and bottomlands.  They go through life at a run. 

They’re about a half-inch long, and iridescent, and one source speculated about the need for/use of iridescence in a nocturnal beetle, noting that their bodies reflect moonlight, but drawing no conclusions about it. 

In their “Guess the Pest” feature (the spirit of which the BugLady objects to on principle), the University of Delaware Cooperative Extension calls TCHGBs “a beneficial predator of slugs and caterpillars.” Their diet also includes a variety of insects including Japanese beetles and some corn borers and armyworms. 

The beetles overwinter as adults and breed in spring; females place their eggs in mud cells that they attach to vegetation. 

The BugLady has trust issues – she tries to get her information from sources she knows are reliable, and she rarely looks at the AI summary that tops all her search results.  In the case of the TCHGB,AI presented a long and very generic (but well-organized) collection of information about the Ground beetle family, disguised as a write-up about TCHGBs (along with the tiny disclaimer “AI responses may include mistakes.”).  Another site – “Picture Insect” (“an Entomologist in your pocket”), one that doesn’t pop up often in her searches and that seems to have been AI’s primary source (and that spelled “Tricolored” the British way) – stated that the “Tricoloured harp ground beetle can emit a bright, bioluminescent glow from its abdomen, a rare trait within its family not primarily known for light production.”  Just the kind of tidbit that the BugLady lives for, except that she couldn’t find any other sources to back that up.  She Googled “ground beetle bioluminescence” with no results.

Caveat emptor!  A motto for our times.

Kate Redmond, The BugLady

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

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