Bug o’the Week – Black Zale Moth

Bug o’the Week
by Kate Redmond

Bug o’the Week Black Zale Moth

Greetings, BugFans,

Zale moths (thank goodness) are not small and grayish (the moth equivalent of LBJ’s – “little brown jobs” – the birding acronym for the sparrow group), and thus they are not destined to languish unidentified in the BugLady’s “X-files” for too long They’re in the moth family Erebidae (from the Latin “erebus,” meaning “from the darkness”), which contains lots of colorful and familiar groups, like the Underwings, Tiger moths, Tussock and Lichen moths, and Zales. It also includes the BugLady’s personal nemesis moth, the Black Witch https://uwm.edu/field-station/bug-of-the-week/black-witch-moth/, one of which may have flown past her house this summer while the BugLady was inside, spotted by a guest who later asked “what kind of moth is big, dark, and kind of tattered-looking?”

Pronounced “ZAH’ lay,” the genus contains almost 40 species in North America.  Adults have wingspreads between 1 ½” and 2,” with wings that are camouflaged and at the same time are often strikingly patterned and even iridescent https://bugguide.net/node/view/1713943/bgimagehttps://bugguide.net/node/view/647825/bgimagehttps://bugguide.net/node/view/2080306/bgimage,

https://bugguide.net/node/view/1731967/bgimage.  And, of course, their wings have those neat little scallops on the edges.  Zale moths are nocturnal, with paired hearing organs on the thorax that allow them to detect the calls of hunting bats.  

Wagner’s Caterpillars of Eastern North America calls the Zales “a large and taxonomically challenging genus.”  

Female Zales lay about 200 eggs that hatch in a few weeks, spend a month as caterpillars, and live less than a month as adults.   Bugguide.net describes Zale caterpillars as “exceptionally muscular …. capable of hurling themselves from their perch when alarmed.”  They feed on young leaves by night – some species eat deciduous leaves, and others prefer conifer needles.  Wagner, et al, in Owlet Caterpillars of Eastern North America, says that caterpillars of some species “are leaf clippers that chew through the petiole, dropping any evidence of feeding activity to the forest floor; the chewed leaves might otherwise be used by birds to locate caterpillars.”  With a few notable exceptions, like the Okefenokee Zale https://bugguide.net/node/view/2108403/bgpage, the caterpillars are pretty drab and twig-like. 

BLACK ZALES (Zale undularis) are found near their host plants – Black locust and Honey locusts.  One source speculated that as Black locust has spread from its original range, the Black Zale has followed it.

Brief Aside: Black locust is a native species that is considered invasive outside its original range, including in Wisconsin.  Wikipedia tells us that “The exact native range is not known…….The native range is thought to be two separate populations, one centered about the Appalachian Mountains, from Pennsylvania to northern Georgia, and a second westward focused around the Ozark Plateau and Ouachita Mountains of Arkansas, Oklahoma, and Missouri.“  Whatever its native range, Black locust has been planted extensively throughout the country.

Although it’s a valuable wildlife plant (hosting, among other things, 67 species of Lepidoptera, while providing cover and seeds for other animals), it has a bad habit of taking over and turning grassland habitats into shady ones (it’s a pioneer – a sun-loving species that produces enough shade for mid-tolerant woody species to establish themselves). The roots of the BugLady’s big locusts are holding the dune together, so she has a moral dilemma. 

Another Brief Aside: The moth was photographed on a layer of wood chips that covers a huge piece of cardboard that covers a nasty, aggressive, persistent ground cover plant called Bishop’s weed (Aegopodium podagraria), aka goutweed, snow-on-the-mountain (a version of Bishop’s weed that has variegated leaves), and a bunch of names that have four letters.  The BugLady’s minions have been fighting it for a few years with fire, vinegar, and now cardboard.  If you don’t have bishop’s weed, don’t plant it, no matter what the nursery folks say, and if you’ve successfully gotten rid of it (without nuking it with chemicals), please tell the BugLady how.  

OK – Back to bugs.

Like most of the Zales, Black Zales are eastern(-ish) moths; buggude.net says that they’re found from Manitoba and Minnesota to New Brunswick, south to Florida and Arkansas.  And, like most of the Zales, Black Zales can show a lot of variation in color and pattern https://bugguide.net/node/view/323477/bgimage,

Adults are mainly seen in the first half of summer, though they can be hard to find when they’re sitting on a tree trunk https://bugguide.net/node/view/1204274/bgimage, and caterpillars can be hard to spot at all https://mothphotographersgroup.msstate.edu/species.php?hodges=8695, especially when they’re feeding on the undersides of leaves.  They overwinter on the ground as pupae, in leaf litter.

Wagner, in Caterpillars of Eastern North America, says that “Zale caterpillars are highly mobile as first instars, often wandering long distances before they begin feeding.  Most prefer young leaf tissue, especially in early instars, then consume older leaves and needles in late instars.

Don’t let the nursery folks sell you Black locusts, either.

Kate Redmond, The BugLady

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

Bug o’the Week – Sand-loving Bembidion beetle

Bug o’the Week
by Kate Redmond

Bug o’the Week Sand-loving Bembidion beetle

Greetings, BugFans,

The Ground beetle family (Carabidae) contains some large and spectacular species https://bugguide.net/node/view/662415/bgpage, https://bugguide.net/node/view/2138426/bgimage, https://bugguide.net/node/view/2216522/bgimage, (including the Tiger beetles https://bugguide.net/node/view/1124395/bgpage), but today’s beetle is neither large nor flashy. It’s pretty fast, though.

With 2,440 species in North America and around 34,000 species worldwide, Carabidae is one of the largest insect families. Most Carabids are active hunters, both as larvae and adults, and many species (but not the tiger beetles) are nocturnal. Other than that, Carabids come in all sizes, shapes, and colors, and habits and habitats. Many are chemically protected, with special glands where they can concoct noxious substances.

Cool fact about Ground beetles: according to bugguide.net, “the front tibia has a prominent notch (antenna cleaner) on the inside near distal end.” 

The BugLady was moseying around on the beach one August day when she spied an impossibly small beetle zipping over the sand.  So (of course) she aimed her camera at it as it ran around her and between her feet.  Bent over, with the 100mm lens about 2 ½ feet above the sand, this was the only shot worth keeping. 

She figured out that it was in the genus Bembidion (though she guessed the species wrong).  Bembidion is the largest genus in the Carabidae, and it’s a complex one.  Evans, in Beetles of Eastern North America, says that “Bembidion is a large genus; species sometimes challenging to identify.”  There are about 1,300 described species that are divided among about 100 subgenera, with more in the pipeline.  About 250 species live in North America, eight of them non-native. 

As a group, they are small (a half-inch or less), slender and somewhat flattened, dark and often metallic, speedy denizens of habitats near the water, especially river banks (though there are some grassland and desert species, too).  Their range is described as (new science words) biantitropical or amphitropical – that is, they live at both southern and (mostly) northern latitudes, away from the tropics.  They tend to appear on the landscape in spring and summer, they prey on tiny invertebrates, and they overwinter as adults. 

The BugLady sent the picture off to BugFan PJ for his thoughts.  He thought he should send it along to a ground beetle specialist, who wrote, “Kate’s culprit is likely Bembidion (subspecies Bracteon) carinula Chaudoir. See https://bugguide.net/node/view/109039. This is an abundant species that runs fast on wet sandy shores of Lake Michigan during warm sunlight in midsummer. They often fly when approached.”  Thanks, Gentlemen – it takes a village.

Most of the few sources of information that she found didn’t list a common name, but the Canadian NWT Species Search website calls it, logically, the Sand-loving Bembidion Beetle.  Its range covers much of Canada and across the northern tier of the US into New England (with some records in Iowa, Kentucky, and New Jersey).  It’s seen on sparsely-vegetated shores, often on dry sand, and though it’s not uncommon, it may be hard to see because it’s only 3/8” in length and it moves along like the Roadrunner.  It’s active during the day, and the adults are good fliers. 

The checkerboard pattern on its elytra is more conspicuous in some individuals https://bugguide.net/node/view/842164/bgimage than in others https://bugguide.net/node/view/51503/bgimage

Other than the fact that it appears on a number of “The Ground Beetles of (Wherever)” surveys and checklists, and it’s a species of Special Concern on Connecticut, there’s not much out there about Sand-loving Bembidion beetles.  As always, several sites offered to tell the BugLady what words rhyme with Bembidion, and yes, you can order a Bembidion beetle Sun catcher and a belt buckle online.

Kate Redmond, The BugLady

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

Bug o’the Week – Jumping Bristletail Retread

Bug o’the Week
by Kate Redmond

Bug o’the Week Jumping Bristletail Retread

Salutations, BugFans,

The BugLady has been busy – here’s a slightly-spruced-up version of an episode that she posted 10 years ago.  The Jumping bristletail that inspired it remains the only one she’s ever seen.

It was found by accident, as many good things are, clinging to one end of a branch that was lifted from the forest floor to get a better view of the mushrooms growing on it.

It turned out to be one seriously ancient critter.  Insects probably got their beginnings 443 to 417 million years ago (mya) during the Silurian Period (for a long time it was believed that insects descended from the millipede/centipede bunch, but evidence now points to origins within the Crustacea).  The oldest insect fossil (so far) is a “sort-of-silverfish” that dates back 396 million years to the Devonian Period.  There are fossil springtails from that period, too, but springtails are not considered insects any more.  The Carboniferous Period (354 to 290 mya) was marked by dragonflies with three-foot wingspreads and by an abundance of cockroaches.  Tracks of Jumping Bristletails have been found in Permian rock (290 to 248 mya) (the upstart dinosaurs didn’t appear until the Triassic Period, some 50 million years later, plus-or-minus).

Jumping bristletails used to be classified with the silverfish (the blameless Jumping bristletail is still lumped with silverfish on some exterminator’s websites), but now they’re in their own order.  In defining an animal scientifically, the groupings move from the most general umbrella to the most specific umbrella.  Kingdom (Animalia) comes first, the biggest umbrella, then Phylum (Arthropoda), then Class (Insecta), then Order, then Family, Genus, and finally Species. 

Jumping bristletails have two different order names.  The newer name is Microcoryphia (“small head”), and the older appellation is Order Archaeognatha (“ancient jaw”), which refers to the way the mandible connects to the insect.  Whichever order name you pick, Jumping bristletails are alone in it.  That 396 million year old “silverfish” had the new-fangled double-jointed (dicondylic) mandible, but Jumping bristletails have the original equipment, a single (monocondylic), knuckle-like joint/articulation that allows its mouthparts to rotate or twist.  Ancient insect jaws probably resembled those of Jumping bristletails, but most insects developed from a side branch that sprouted from the insect family tree early on.  Some scientists consider the Jumping bristletail to be the least evolutionarily changed of any living insect – a chip off a very old block.

There are two Jumping bristletail families worldwide, the largest of which is Machilidae.  Both families occur in North America, as do about two dozen of the 350 to 450 species of the world’s Jumping bristletails (we even have an introduced species). 

(No – the BugLady is not going to try to name a genus or species for this one, but if she was a betting woman, she’d put a little money on Pedetontus saltator.)

Back in the (Permian) day, there were many wingless insects.  Today, the vast majority of insects have wings, and those that have wings have two pairs of them.  Most of the species that are wingless derive from ancestors that once had them.  Not so the Jumping bristletail and the silverfish, who are primitively/primarily wingless – their ancestors never enjoyed flight. 

As a group Jumping bristletails are drab (though a close look may reveal a variety of color patterns, and the BugLady’s bristletail is downright iridescent), scale-covered, cylindrical, hump-backed (silverfish are flat), and generally less than three-quarters of an-inch long.  At one end they have sensory antennae and both simple and compound eyes (with their simple eyes, silverfish are blind to all but light and dark), and at the other end, three caudal filaments – two sensitive cerci and a central terminal filament.  Fringes of hairs on the rear filaments explain the “bristletail” part.

They have the requisite six legs, but attached to the underside of some abdominal segments are additional pairs of short, moveable appendages called “styli” (plural of stylus) that serve as sensors of their substrate and that may be vestigial legs left over from their ancestors.  Jumping bristletails dehydrate easily and must absorb water from their environment through tiny, paired sacs that are located on several abdominal segments and that work like pockets turned inside out (OK – “membranous, eversible sac-like vesicles”).  Here’s an article with pictures showing their iridescence and a video of bristletails in action https://www.welcomewildlife.com/jumping-bristletails-not-silverfish-not-pests/   

As their name suggests, they jump – six inches and more – which silverfish can’t do.  This they accomplish by pushing up with their legs while contracting the muscles in their abdomen to arch their body downward.  They can run fast, too.  Jumping is their main defense, but like silverfish, a dense covering of scales renders them slippery and helps them escape from the clutches of their predators.

In the “Is There a Video of That?” category (and there undoubtedly is one), consider Stephen P. Yanoviak’s research that looked at Jumping bristletails for clues to the evolution of insect flight.  When a Jumping bristletail leaps from tree to tree, its drop is augmented by “steering,” using the long terminal filament (“directed aerial descent”) (kind of like a flying squirrel).  Yanoviak dusted Jumping bristletails with orange fluorescent powder and dropped them from branches high in rainforest trees.  Results showed that the filament was vital to a successful glide and landing, and Yanoviak suggests that because these wingless, arboreal insects had “flight” under control, winged flight probably originated from terrestrial insects.

Jumping bristletails live in a wide variety of conditions, from Arctic to desert, and they especially like leaf litter, bark, rock crevices, and rocky seashores.  The North Carolina State University Entomology Pages rank Jumping bristletails as “common in grassy or wooded habitats.” They are found in the nooks and crannies of the world, where they shelter during the day and from which they perambulate at night.  They rarely come indoors.  

Herbivores and decomposers/recyclers, they use their mouthparts to feed on algae, fungi, lichens, mosses, and soft, decaying organic material, though a few sources said that they eat tiny invertebrates, too (one source said that they pick at their food rather than chewing it).  They don’t/can’t bite people.  They are eaten by birds, centipedes, spiders, mites, ants, and flies.   

Ancient mouth; ancient winglessness, ancient reproduction, and ancient metamorphosis.  Males court, sometimes with elaborate dances, then leave a sperm packet for her to pick up (indirect sperm transfer).  She may lay as many as 30 eggs, but to lay more, she must dance again.  Some species skip the dance and reproduce by parthenogenesis – females reproduce without input from males.  Young Jumping bristletails have an ametabolous development – they start as miniatures of the adults and simply grow, shedding eight times over the course of about two years before reaching adulthood.  Unlike most other insects, they continue to shed as adults and may live for two additional years.  Each time they molt, they must first cement themselves to the substrate – a stick, rock, etc. – using fecal material as a glue.  Should the glue fail, the insect will not molt, but die. 

Interesting Jumping bristletail facts:

  • Take yourself to a woodland some night and shine a flashlight on a spot in the leaf litter – Jumping bristletails are attracted by light and will appear after about 15 minutes.  Their eyes will glow in the flashlight’s beam.
  • According to a blog called “myrmecos” by entomologist and photographer Alex Wild, “In California these flightless insects are common around harvester ant nests.  I don’t think they have any sort of specialized relationship with ants, except perhaps finding the warm microclimate of the mound surface agreeable.”

Small, yes.  Old, oh yes.   But not uncomplicated.

Kate Redmond, The BugLady

PS – Road Trip!!!!   https://metropolismag.com/projects/montreal-insectarium/?utm_campaign=ME_Bi-WeeklyNewsletter&utm_medium=email&_hsmi=283277107&_hsenc=p2ANqtz-80i2GYCnKZBaxBvmnF77oSWJaFMUJkA-1MS5TSJ7lJITS8EIUNOXKzZoyiTckeKKnyDlP3afGn5wfxOGD2idMkiYnURdqXS_PSBdpqxQKel8kD75o&utm_content=283277107&utm_source=hs_email

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

Bug o’the Week – Two Odd Little Flies

Bug o’the Week
by Kate Redmond

Bug o’the Week Two Odd Little Flies

Greetings, BugFans,

The BugLady loves finding species she’s never spotted before – there are many thousands of insects she has yet to photograph, but that’s a matter of “right time; wrong habitat; more road trips.”  This year’s new bugs were mostly wasps, flies, and katydids – stay tuned.  And, as vintage BugFans know, the combination of the BugLady’s hyperopia (farsightedness) and her camera lenses (first a 50mm macro lens, then a 70, and now a 100mm) lure her into the world of little stuff.

They are in different families, but (besides size), what today’s two flies have in common is a very limited on-line presence.

FLY #1 – Heteromyia prattii

People frequently ask the BugLady about the clouds of midges they see dancing in the air, especially at the start and end of the bug season.  Those are mostly cold-tolerant species of non-biting midges in the family Chironomidae – fragile, mosquito-y-looking flies with long front legs https://bugguide.net/node/view/2260548/bgimage.  When she found this little fly in the brush near a wetland in June – a fly with a husky-looking thorax, bulging front legs, patterned wings, and extraordinary back legs – she was clueless (thanks, as always, PJ). 

It’s in the family Ceratopogonidae, the Biting midges (aka Punkies and No-see-ums).  Googling No-see-ums results in a flood of Extension and Exterminators sites.  Why?  Many female Biting midges sip the blood of reptiles, of humans and other mammals, and even of other insects in order to fuel their egg-laying.  To this end, their mouthparts are adapted for slicing through skin.  Among their targets are humans who are enjoying the outdoors – their bite is painful; the aftermath is irritating; and the lesions may last for weeks if the victim is allergic.  To top it off, some Biting midges can be vectors of disease in humans and livestock, here and abroad (none affect humans in North America).  Males don’t bite, and both males and females are fond of nectar.   

Biting midges are found across the continent and around the world.  Their larvae grow up in moist/wet, sheltered spots, and the adults are found in early summer in woodlands and around wetlands, both saltwater and fresh. 

Heteromyia prattii (no common name) is found in the eastern US and into southern Canada, but most of the dozen or so other genus members are tropical.  Its larvae live in shallow water and wet edges.  Like other Ceratopogonids, the adults are small – about 4mm (¼”-ish).  Here are some better pictures than the BugLady managed https://bugguide.net/node/view/2265258/bgimagehttps://bugguide.net/node/view/1020149/bgimage

About this species, little has been written, but more is known about its tribe, Heteromyiini.  In a paper published in 1978, Wirth and Grogan summarized the natural history of the tribe, going back to early observations of the fly.  They wrote So far as known, the adult females are predaceous on chironomid midges and other smaller, soft-bodied insects,” and they quoted from an 1856 paper “The species whose femora are armed with spines make a prey of other small insects, which they pierce with their sharp proboscis.”  A century later, Downes wrote that “The females of insectivorous Ceratopogoninae (typical genera: Ceratopogon, Stilobezzia, Clinohelea, Palpomyia) feed on small insects that are captured in flight. The prey is almost always the male of species of Nematocera and Ephemeroptera, and it is frequently, and probably typically, captured in the male swarms (mating swarms) that are so often produced in these groups. They thus reach, perhaps almost indifferently, the male swarm of their own or another species and proceed to capture prey.”  His account included a picture of a female Biting midge eating the male she was copulating with.  The larvae feed on invertebrates that are even smaller than they are, newly-hatched midges, and egg masses. 

FLY #2 – Dilophus stigmaterus (no common name)

The BugLady noticed Fly #2 when she was hauling her gear up the stairs of the hawk tower in September.  A few of the goldenrods at the base of the tower were covered with these speedy little flies, but plants not too far away had none. 

They’re in the March fly family Bibionidae, called March flies because many of the species emerge in spring.  If you’ve been to Gulf Coast, you’ve probably encountered swarms of March flies called Love bugs, in flagrante delicto (second meaning) (about Love bugs, bugguide.net says that because they became very numerous very abruptly, “There are a number of popular myths about this species, including that it was a lab creation designed to control mosquitoes.”).   

It’s not surprising that the BugLady saw a bunch of these flies.  March fly larvae live gregariously on/in the ground and under leaf litter (some are found in compost heaps), eating rotting plants and live plant roots and contributing to soil building.  They often emerge as adults synchronously, forming large mating swarms.  Females lay their eggs in small holes that they dig in moist soil.  The adults’ brief lives are focused on romance.  Those species that feed (not all do) eat nectar, pollen, and honeydew, and some March flies are important pollinators, especially of irises and orchids.

Dilophus stigmaterus is sexually dimorphic – males are all black https://bugguide.net/node/view/538047/bgimage, and females have a reddish thorax https://bugguide.net/node/view/1158066/bgimage, and both have a ring of tiny spines on their front tibias.  A long “nose” (rostrum) that is about as long as the antennae, and extended mouthparts that are about three times as long are key characteristics for the species.  Curious about how Dilophus stigmaterus lives its life?  The BugLady is, too, but other than a very detailed anatomical description of the species written by WL McAtee in 1922, and the fact that they’ve been recorded nectaring on Boneset, she couldn’t find anything else about them.  Remember – according to the Smithsonian, there are around 91,000 described species of insects in the US and probably another 73,000 waiting to be discovered/described.  While they all do their bit to make the world go ‘round, many do so very unobtrusively. 

Kate Redmond, The BugLady

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

Bug o’the Week – Lined Orbweaver Spider

Bug o’the Week
by Kate Redmond

Bug o’the Week Lined Orbweaver Spider

Howdy, BugFans,

When the BugLady spotted this small spider on its horizontal web (while she was officially censusing butterflies and dragonflies), she thought it might be one of the sheet-web spiders.  Fortunately, she has a Spider Guy, and he set her straight (thanks as always, BugFan Mike).

Turns out that it’s a small orbweaver called the Lined orbweaver (much has been written in BOTW about some of the larger species in the orbweaver family Araneidae).

Orbweavers, famously, spin circular/orb-shaped trap webs (the silk that makes up the radii isn’t sticky but the silk in the spiral is).  The spiders often hang from the web’s center during the day, or they hide in a nearby retreat.  They monitor the vibrations of the web, and when an insect sticks and struggles, they’re all over it.  Harmless prey is bitten, stunned, and wrapped for later consumption https://bugguide.net/node/view/1565567/bgimage, but prey that bites back or stings is wrapped and immobilized before the coup de grace is delivered.  One source said that the orbweavers are the only spiders that chew their food. 

Many orbweavers (but not this one) spin their webs at night and eat the day-old web, thereby recycling the proteins.  They have eight eyes and poor vision, and they communicate via vibration and chemicals (pheromones).  According to an article entitled “Orb-weaver spider uses web to capture sounds” on a Cornell University College of Arts and Sciences Animal Behavior website, “Orb weaver spiders are known to make large webs, creating a kind of acoustic antennae with a sound-sensitive surface area that is up to 10,000 times greater than the spider itself” (another article said that they “outsource” their hearing).  They both can and will bite (not dangerously) if mishandled, so — don’t.   

There are more than 3,100 species of orbweavers throughout the world.   

THE STABILIMENTUM RABBIT HOLE

Some orbweavers, especially those that are active in the daytime, that spin webs in the open, and that leave the webs up for a few days (like spiders in the genus Argiope), take the time and energy to produce a heavy silk and to weave it into a non-sticky, thickened area in the web called a “stabilimentum” https://bugguide.net/node/view/1125407/bgimage.  Why? Short answer – no one knows for sure, but stabilimenta might serve different purposes for the various species that deploy them.  Nocturnal spiders and those with unobtrusive webs don’t make them.

Originally, scientists believed that these structures strengthened the web (hence the name), but the silk is only loosely attached, and the web fares just fine if the stabilimentum is removed. 

In other hypotheses, the stabilimentum:

  • provides camouflage for a spider that’s sitting in the middle of the web https://bugguide.net/node/view/1585298/bgimage
  • fools potential predators into thinking the spider is bigger than it is https://bugguide.net/node/view/1884530/bgimage;
  • reflects UV light, like flowers do, and therefore attracts insect prey (but – the silk isn’t sticky, and an insect that flies into it won’t get stuck);
  • makes the surrounding web less noticeable by comparison;
  • attracts the male of the species when the female is receptive;
  • is part of the spider’s thermoregulatory strategy;
  • and/or, protects the web by making it more visible to birds that might blunder through it (though some spider predators have learned to search for stabilimenta).

Addenda: In experiments, some researchers have noted that webs with stabilimenta catch 30% fewer insects, presumably because they are more visible, but other equally reputable scientists say that webs with stabilimenta catch up to 41.6% more prey.  Sated spiders seem more likely to make stabilimenta.  Some species change the shape of the stabilimentum as they age.  

The BugLady thinks it’s just grand that these things haven’t been figured out yet.

THE LINED ORBWEAVER (Mangora gibberosa) is the most common of the seven members of its genus that occur north of the Rio Grande (gibberosa is from a Latin word “gibber” meaning “hump-backed” and “osa” meaning “full of” or “extremely”).  Another 180 or so genus members live in Central and South America.  Lined orbweavers are found in open areas – gardens, grasslands, roadsides and woodland edges – in the US east of the Rockies and into Canada. 

These are small spiders https://bugguide.net/node/view/712593/bgimage, with females measuring ¼” and less, and males much smaller.  Like other orbweavers, they come in a range of colors, with some with more lines, and some with more spots – https://bugguide.net/node/view/823822/bgimagehttps://bugguide.net/node/view/1059263/bgimage. Good pictures here: https://www.marylandbiodiversity.com/view/8531 and here’s a nice “face-to-face” https://bugguide.net/node/view/1423274/bgimage.

The webs they build in sheltered areas in grass or brush may be horizontal or slightly angled and are sizable webs (about 12” across) for such a small spider. They have a “bull’s-eye” stabilimentum that is sometimes open and sometimes more solid https://bugguide.net/node/view/1236100/bgimage and that is often occupied by its resident during the day.  

The “Arachnids of North Carolina” website tells us that in October, it “builds web at dawn orienting its web perpendicular to the rising sun, to warm up in its web quicker.”  And, adds the usaspiders.com website, “Such orientations to sunrise would maximize the surface area of the body exposed to insolation and allow the spiders to warm quickly during the coolest part of the day.  A quick warmup in the morning may be advantageous to prey capture, particularly during the cooler months of the year.” 

Female Lined orbweavers conceal their egg sacs by folding a leaf around them and webbing it shut.  Although the eggs within the sac hatch in fall, the tiny spiderlings stay inside the sac through winter (absorbing yolk material in their abdomen) and emerge in summer. 

The tiny Lined orbweaver, of course, is up against competition from other spiders as it tries to make a living.  In a study published about 15 years ago, Richardson and Hanks looked at the division of potential prey among four species of orb-weaving spiders living in close proximity in a grassland.

As suspected, it was not a zero-sum game – the spiders survived by occupying different niches within their habitat.  The researchers noted the spiders’ sizes, the web size and height, the density of the webs’ “mesh,” and the kind of plant that the web was attached to.  They found that spider size (and therefore the size of prey they were able to subdue) allowed a variety of species to coexist.

Kate Redmond, The BugLady

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

Bug o’the Week – Southern Corn Billbug

Bug o’the Week
by Kate Redmond

Bug o’the Week Southern Corn Billbug

Greetings, BugFans,

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

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

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

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

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

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

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

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

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

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

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

Kate Redmond, The BugLady

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

Bug o’the Week – Sculptured Resin Bee

Bug o’the Week
by Kate Redmond

Bug o’the Week Wildflower Watch – Swamp Milkweed

Howdy, BugFans,

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

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

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

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

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

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

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

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

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

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

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

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

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

Time will tell.

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

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

Kate Redmond, The BugLady

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

Bug o’the Week – Wildflower Watch – Swamp Milkweed

Bug o’the Week
by Kate Redmond

Bug o’the Week Wildflower Watch – Swamp Milkweed

Howdy, BugFans,

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Kate Redmond, The BugLady

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

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

Bug o’the Week
by Kate Redmond

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

Howdy BugFans,

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Fun Facts about Turkey Vultures:

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

The BugLady is looking forward to their return in spring.

Kate Redmond, The BugLady

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

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

Bug o’the Week
by Kate Redmond

Bug o’the Week Monochromatic Stink Bug-Hunting Wasp

Howdy, BugFans,

Another wasp with a dynamite name!

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

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

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

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

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

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

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

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

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

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

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

Kate Redmond, The BugLady

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

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