Bug o’the Week – Two-spotted Tree Cricket

Greetings BugFans,

The BugLady had a visitor at her front door the other day – a Two-spotted tree cricket.  When they think of tree crickets, most people picture a delicate, flat, green member of the genus Oecanthus (https://bugguide.net/node/view/883267/bgpage).  Oecanthus tree crickets, with a brief nod to the Two-spotted tree cricket, were celebrated in a previous BOTW https://uwm.edu/field-station/tree-crickets/.  Today’s story is about that other tree cricket.

The Two-spotted tree cricket (Neoxabea bipunctata) (family Gryllidae) used to be grouped with the Oecanthus but was reclassified into the Neoxabea.  According to bugguide.netNeoxabea means “new tree cricket” – Xabea being yet another tree cricket genus and the one that the TSTC was assigned to before it was an Oecanthus.  Neoxabea are called the “smooth-legged tree crickets” because the Oecanthus have spines on their hind legs and Neoxabea don’t.  There are about a dozen species in the genus Neoxabea worldwide, but the TSTC is the only species north of the Rio Grande unless you count the Brownsville tree cricket (N. formosa), which barely makes it over the border and whose classification is a bit problematic.  Here’s a glamour shot – https://bugguide.net/node/view/1475840/bgimage.

There was a reference to a common name for the TSTC in Ohio – “itch bug” – that the BugLady couldn’t find anything more about.  Tree crickets, though they are (barely) capable of biting human skin, rarely do (in the BugLady’s experience, they’re too busy exiting the scene).

TSTCs, as one reference pointed out, are found over the eastern half of the country in approximately the same footprint as the original, eastern deciduous forests.  They are associated with oak, apple, maple, white pine, and a variety of other trees, and also with wild grape and sunflower.  They aren’t seen as often as their Oecanthus cousins because they tend to live higher off the ground in dense vegetation, and males sing from the undersides of leaves.

The cut of their jib is distinctly different from the other tree crickets.  Unlike the Oecanthus https://bugguide.net/node/view/37247/bgimage, they tend to be pinkish, and the male’s wings are less flared https://bugguide.net/node/view/1611999/bgimage.  Females have two dorsal spots; males don’t.

TSTCs have gradual metamorphosis – nymphs resemble the adults and there’s no resting/changing/pupal stage.  Both adults and nymphs feed at dusk and by night on the same diet of tiny insects, bits of leaves, pollen, and fungi (and the BugLady wonders if maybe the one on the screen was grazing on the algae that grows there).  They are preyed upon by wasps, including grass-carrying wasps, of previous BOTW fame, which collect them to cache for their young.

The male’s song is described as a broken trill (one source described it more authoritatively as “A plaintive, dissonant, buzzy trill at about 3.5 kHz, with a distinctive “screaming” quality.”).  He produces sound by rubbing together the ridges on each wing (a “scraper” and “file”).  In the spirit of cold-bloodedness, the warmer the air is, the more trills he generates, and he hedges his bets by chewing a hole in a leaf and positioning his wings and body over it so that the leaf acts like a megaphone.  The tympanum (hearing organs) on her front legs must be tuned to distinguish his species from others at whatever rate he’s singing.  She prefers males that sing “bass,” because they’re probably bigger and therefore have more sperm.

In a paper called “The Mating of Tree Crickets,” David Funk explains that because the sound is amplified backwards from the male, females tend to approach from the rear. He says that “When a male senses the presence of an approaching female, he stops singing and turns around to touch her with his antennae. It is thought that by “tasting” her in this way, he is able to assure that she is a member of the same species and therefore an appropriate mate.”

Their reproductive strategy includes a practice called courtship feeding. There’s a groove on the top of his thorax, between his wings, and into it oozes a substance produced by the metanotal gland, a substance that is irresistible to the female (sometimes unpaired females approach and try to feed, too).  When the female climbs on his back to reach it, she is positioned so that the male is able to insert a spermatophore into the appropriate opening.  She clings to his back, feeding, as he hangs from the vegetation https://bugguide.net/node/view/1778045/bgimage.

As she feeds, the spermatophore empties into her oviduct, and when she’s finished with the metanotal fluid, she eats the also-nutritional, empty spermatophore, too.  Says Eric Eaton in his bugeric blog, the female would undoubtedly eat it [sooner] if she did not have the more attractive metanotal secretion to lick instead.”

She punches her ovipositor deep into a small branch https://bugguide.net/node/view/238538, inserts an egg and, says Bentley B. Fulton in a 1915 Technical Bulletin for the New York Agricultural Experiment Station, “Just before depositing the egg, and while the ovipositor is embedded for its full length in the bark, the female forces out a drop of excrement, which by stretching out the tip of the abdomen, she fastens to the bark just below the hole.  After withdrawing the ovipositor she moves back, picks up the drop with her mouth and places it over the opening.  Several minutes are then spent packing it in and smoothing it out. https://bugguide.net/node/view/259844.  Fulton’s article includes some lovely, pre-digital illustrations https://orthsoc.org/sina/s576lf15.pdf.

The eggs hatch in spring and the nymphs are pretty cute – the butts-up position is a common pose https://bugguide.net/node/view/1834770/bgimage.  Here’s an excellent set of pictures of ages and stages https://orthsoc.org/sina/601a.htm, plus sounds.

Sometimes the punctures she makes as she’s ovipositing damage woody plants by weakening the twigs, but it’s seldom a problem, and one Exterminator’s website included a link to “detailed information about this fascinating insect.

Go outside.  Listen!

Kate Redmond, The BugLady

Bug o’the Week – Have You Seen This Fly???

Howdy, BugFans,

The BugLady was poking around in a wetland toward the end of May when the Black Chokeberry (Aronia melanocarpa) was in bloom.  As she photographed its flower, a syrphid fly or two buzzed in.  Any flower shot is enhanced by having an insect in it, right?

Syrphid/Flower/Hover flies (family Syrphidae) are the often-tiny, usually-black-and-yellow bee mimics that perch lightly on or hover above flowers.  Some wear patterns that are amazingly etched (an “up-side” of photography is that instead of a fleeting glance, the BugLady gets to put their pictures on the screen and enjoy the intricate tracery https://bugguide.net/node/view/2023052/bgimagehttps://bugguide.net/node/view/1611313/bgpagehttps://bugguide.net/node/view/1960381/bgimage).  Although they are designed to look like bees, they are harmless, and they’re important pollinators.

The BugLady got pretty excited when she put the picture up on the monitor – she had never seen a black syrphid fly with white spots before.  When she revisited the wetland a week later as the chokeberry faded, she couldn’t find the fly again.

Turns out that it was a Black bog fly (Parhelophilus porcus).  Parhelophilus is a small (20 species) Holarctic genus (meaning that they’re found around the northern half of the globe) with 10 species in North America.  There’s another, fairly similar, black and white Parhelophilus that also occurs in Wisconsin, but the rest of them are yellow and black.  Adult Parhelophilus flies are mostly recorded eating the nectar and pollen of asters and other composites, but in most of the few pictures that the BugLady could find of this fly, it was on white flowers in the viburnum and rose families.

Parhelophilus larvae are numbered among the rat-tailed maggots; they live in shallow waters of ponds and slow streams and, typical of the tribe Eristalini, breathe through an extended siphon at the rear of their abdomen as they recycle decaying vegetation with the other end https://bugguide.net/node/view/815670.

Here’s what the BugLady found out about the Black bog fly:

  • It is found way north, well into the Arctic.  Most of the pictures on bugguide.net were taken in New Brunswick.  It’s on the Finnish iNaturalist site, and there were some Russian hits.

  • It is a pollinator and recycling agent whose presence indicates a healthy bog.

  • The Aquatic Insects of Michigan lists it as being “widespread” in Wisconsin, and while it may be widespread, it is in fact a rare, habitat specialist here.

  • The same source says that “the systematics of the family are in flux.”

  • The larva of the Black bog fly has not been identified or described, nor have its habits been studied.

  • It looks a whole lot like Parhelophilus sibiricus, a syrphid fly that’s restricted to bogs in Siberia, and it could be the same species.

  • Writing about it in 1997, researcher F. Christian Thompson tells us that “Most of the known sites for porcus are the typical kettlehole bogs (Bingham Pond, Wilson Mills), but some (Laurel Lake site) are better described as fens bordered by spruce, fir and hemlock ……… Unfortunately, for most collected specimens, no site information is available.

  • The Wisconsin Insect Research Collection contains nine specimens of the Black bog fly, all of which were collected in Door County in 1951 (thanks, BugFan PJ).

That’s it.

Go outside – find cool stuff!

Kate Redmond, The BugLady

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

Bug o’the Week – Northern Amber Bumble Bee

Howdy, BugFans,

This one’s dedicated to BugFan John – it was an honor.

The BugLady has been enjoying an abundance of bumble bees on the prairie recently, despite the fact that, along with the start of the tree cricket chorus, it is a sure sign of the impending autumn.

Quick and dirty bumble bee review:

They’re important pollinators.  They are not aerodynamically designed.  Most native bees are solitary, but bumble bees live in colonies headed by a queen, and unlike their solitary cousins, will sting to defend the nest.  Because of their ability to raise the temperature inside their thorax by shivering their wing muscles, they can fly in pretty chilly weather (other insects can do this, too, but bumble bees are the champs, warming from 55 to 98 degrees Fahrenheit in just six minutes).  They deliver ecosystem services and are considered “keystone species” – species whose absence would affect their communities (no bees = no fruits and seeds = no wildlife).  Many bumble bee species are in trouble.  For more details about all that and more, see these previous BOTWs https://uwm.edu/field-station/bumble-bee-redux/https://uwm.edu/field-station/celebrating-bumblebees/, and https://uwm.edu/field-station/rusty-patched-bumble-bee/.

“Bumblebee” or “bumble bee?”  It’s the same rule that governs the names of flies.  The folks at Minnesota Seasons explain: “The Entomological Society of America follows the convention suggested by R. E. Snodgrass, author of Anatomy of the Honey Bee (1910), when assigning common names to insects. Snodgrass states, ‘If the insect is what the name implies, write the two words separately; otherwise run them together. Thus we have such names as house fly, blow fly and robber fly contrasted with dragonfly, caddisfly and butterfly, because the latter are not flies, just as a dandelion is not a lion and a silverfish is not a fish. The honey bee is an insect and is preeminently a bee; ‘honeybee’ is equivalent to ‘Johnsmith.’”

So – the Northern amber bumble bee (Bombus borealis) aka the Boreal bumble bee is a medium-large bee in the bumble-honey-carpenter-cuckoo-digger bee family Apidae.  Called “amber” because it is, and “northern” because its range extends east from the Rockies across Canada and the northern US.  Its former range dipped farther south, even into Georgia at the higher elevations of the Appalachians.

Bumble bees need three habitats that are not too far apart – one for foraging, one for nesting, and one where the queen overwinters.  Northern Amber bumble bees are found in grasslands and agricultural fields near woods.

Their biographies are similar to those of other bumble bees.  Newly-minted queens mate in fall and overwinter on the ground, under cover.  They emerge in late May/early June in Wisconsin (not one of the super-early species) and make a nest that’s usually underground but could be in a rock pile, tree hole, or clump of grass.  South-facing, abandoned rodent burrows are favorite spots, and she often must fend off other queens who have their eyes on the same real estate.

She cares for the first brood herself, feeding nectar (carbs) and pollen (protein) to the larvae, and if it’s chilly, sitting on the eggs and using her thermoregulatory abilities to warm the brood patch on the underside of her thorax (her daughters will later regulate the temperature of the nest).  She hands off the child care, foraging, and nest maintenance duties to them when they become adults (the BugLady read somewhere that individuals in this initial brood may be smaller, because they had only one caregiver).  Populations peak in late summer as a crop of males is produced, but only the new queens will make it through the winter.

Bumble bee species have different tongue lengths, designated as “short,” “medium,” and “long,” and the length of their tongues determines what flowers they feed on.  Of course, some short-tongued bees have devised a “work-around” – making a hole at the base of a tubular flower and lapping nectar from the outside.  Northern amber bumble bees are long-tongued bees, and although you find them on composites and roses, they are able to extract nectar from the tubular flowers of clovers and vetches.

According to the Xerces Society, “more than a quarter of North American Bumble Bees are facing some degree of extinction risk.”  Northern amber populations are vulnerable along the southern edge of its range, especially in the East, but they seem to be stable in Wisconsin.  Minnesota has seen a large shrinkage of territory occupied, with the range shifting northward.

One problem in censusing bees is a phenomenon called “Shifting Baseline Syndrome.”  There are few long-term studies of bumble bees, so today’s scientists are starting in a hole – they’ve never seen the bees at their earlier population levels, and the present, diminished populations are their “baselines.”  There have been some studies of historical bumble bee numbers using museum collections; these searches show a loss both of diversity and of range starting as agriculture intensified in the middle of the last century, and some species are now “locally extirpated” (locally extinct).

Some studies suggest that the bumble bee species that are declining tend to have shorter lists of plants that they forage on, but other factors, like climate, could be contributing.  Like honeybees, bumble bees are an industry, with captive bees carted around the country.  Some of the bumble bees that are contracted out to pollinate greenhouse crops are not native, some carry diseases, and some escape to infect native bees.

How can we help?  Bee-friendly plantings (bee-friendly plantings, bee-friendly plantings), bee-friendly buffers, including hedgerows around agricultural fields and along roads, bee surveys (https://wiatri.net/inventory/BBB/getInvolved/), and fewer herbicides and pesticides.  Since rodent burrows are at a premium, some researchers are experimenting with manmade nest boxes.

Here is more information about bumble bee ID:

https://www.fs.fed.us/wildflowers/features/posters/EasternBumblebeesPoster_reduced.pdf

https://apps.extension.umn.edu/environment/citizen-science/bee-atlas/bumble-bees/docs/bumblebee_species_slides.pdf

https://www.fs.fed.us/wildflowers/pollinators/documents/BumbleBeeGuideEast2011.pdf

Go outside – watch bumble bees!

Kate Redmond, The BugLady

Bug o’the Week – Silver-bordered Fritillary Butterfly

Howdy, BugFans,

The BugLady’s excursions onto the prairie are always enhanced by the sight of the almost-monarch-sized (2 ½”-3 ½” wingspan) Great Spangled Fritillaries sailing along among the flowers https://bugguide.net/node/view/1995412/bgimage.  They come by their names honestly – great and spangled indeed https://bugguide.net/node/view/61315/bgimage!  For more information about them, see https://uwm.edu/field-station/great-spangled-fritillary/.

This summer, she’s been lucky enough to find these beautiful, also-spangled, Silver-bordered Fritillaries (Boloria selene) alternately bustling and gliding along at the margins of wetlands.  They are in a different genus than the Great Spangled – Boloria are called the lesser fritillaries – and with 1 ½” to 2” wingspans, they are noticeably smaller.  Selene was goddess of the moon in ancient Greek mythology; a previous scientific name is Brenthis myrina, and an old common name for this species is “little myrina,” which the BugLady doesn’t understand, because myrina refers to the Amazon mythology.

Fritillaries are in the brush-footed butterfly family Nymphalidae – butterflies whose first pair of legs is reduced and “brushy” and who walk around on their second and third pairs of legs.

Silver-bordered Fritillaries are found around marshes, sedge meadows, and bogs across the northern half of the US and into Canada (in the southern part of their range they may live at higher elevations), and at another location – more about that in a sec.  They are homebodies that do not disperse enthusiastically from the enclaves where they are found.

Males patrol for females.  Females lay eggs on violets, their caterpillars’ sole food plants, though sometimes she puts her eggs on the ground or on grasses near violet plants, and then her offspring must find their first meal for themselves.  They don’t have a favorite violet – whatever’s growing nearby works for them – and they don’t appear to use non-native violet species.  Adults nectar on members of the composite, pea, and milkweed families.

They produce at least two broods each year, and the final brood overwinters as caterpillars, sheltered on the ground, in a stage of dormancy.  Some of these overwintering larvae are half-grown when they tuck in for the winter, and some are fairly recently hatched, so the appearance of adult butterflies is somewhat staggered after they awake, resume feeding, and complete their metamorphosis in spring, a phenomenon that Scudder investigated in 1889.

Silver-bordered Fritillary don’t adapt rapidly to change, and their populations are decreasing across their range.  Their numbers probably rose as European settlers whacked back the endless forests of the eastern US, creating favorable habitat.  But the resulting agricultural landscape was not friendly to them either, because wetlands were drained (so the land could be “more productive”), and because their violets were plowed up or were pushed out by the European crops.  According to Massachusetts Butterflies, roadside ditches are emerging as important habitat for Silver-bordered Fritillaries in that state.  Food specialists are, by nature, closer to the abyss than are generalists.

Spraying for gypsy moths threatens them, climate change is thinning populations of this northern-oriented species across the southern edge of its range, and they continue to be bothered by habitat loss and habitat fragmentation.

If you google Boloria selene, you’ll also get hits from across The Pond, where the Silver-bordered Fritillary is known as the Small Pearl-bordered Fritillary (as one source said, “from the series of ‘pearls’ that run along the outside edge of the underside of the hindwing”).  It’s found from Great Britain through Europe and into Asia, and, alas, its populations are declining abroad, too, due to habitat change brought by agriculture.

Like the American members of the species, the Small Pearl-bordered Fritillary is a fairly sedentary butterfly that doesn’t travel far from its natal wetland.  When habitat gets fragmented, populations get isolated, and genetic diversity diminishes.  Research indicates that when siblings of this species mate – a possibility that becomes more likely with isolation – their offspring aren’t viable.

Apropos of nothing, as the BugLady’s Dad used to say, the BugLady found this cute little bug while doing an unrelated search https://bugguide.net/node/view/22991/bgimage (she has photographed the adult, which is also awesome!), and this blog.whose first article is about insect use of swamp milkweed http://www.hiltonpond.org/ThisWeek210811.html.

Kate Redmond, The BugLady

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

Bug o’the Week – Big Orbweaver Spiders Revisited

Greetings, BugFans,

The BugLady has been having too much fun recently, taking pictures, so she dusted off this episode from November, 2012 and added some new words and new pictures.

For years, the BugLady has been amassing shots of big, showy orbweaver spiders in the spider family Araneidae (Charlotte’s relatives), aka the Garden spiders.  She knows that “picture-keying” has its limits, and that there’s a lot of variability within spider species (these are all Marbled orb weavers), https://bugguide.net/node/view/1618434/bgimagehttps://bugguide.net/node/view/1905479/bgimagehttps://bugguide.net/node/view/1304801/bgimagehttps://bugguide.net/node/view/1302073/bgimagehttps://bugguide.net/node/view/1273874/bgimagehttps://bugguide.net/node/view/1166829/bgimagehttps://bugguide.net/node/view/718340/bgimage, and that real scientists use microscopes, so she has her fingers crossed about IDs.  If she were smart, she would be satisfied just to get the genus right.  Bugguide.net has a lot of helpful images, and so does Spiders of the North Woods by Larry Weber.

FYI, in the course of her research, she has seen the name spelled orb weaver, orb-weaver, and orbweaver.

Orbweavers have been practicing their craft for some 140 million years now (full disclosure – there are some non-orbweavers that weave orb-type webs, and a few orbweavers that don’t).  With more than 3,500 kinds of Araneidae worldwide (180 north of Mexico), they account for about a quarter of spider species.  They can be found in any habitat where there’s something to hitch a web to, but some species prefer woodlands, wetlands, etc.

Although orbweavers have eight eyes (two rows of four, and the middle four form a trapezoid), their vision is not so good.  Their legs are adorned with bristles/spines and have an extra claw on each foot (that third claw helps them to manipulate silk as they spin it and to traverse the non-sticky parts of the web).  They range in size (body length) from ¼” to an inch-plus; females are often considerably bigger than males and have large spherical abdomens.  Some species are nocturnal, and others are diurnal.

Building a web is an amazing feat that involves sending a sticky line out into the breezes.  If it catches on something, the spider forms the “spokes” of the wheel with non-sticky web and then uses sticky silk for the spiral.  It takes about an hour.  For a more comprehensive explanation of the process, see https://www.smithsonianmag.com/smithsonian-institution/ask-smithsonian-how-do-spiders-make-webs-180957426/.  Many nocturnal orbweavers eat their dewy web in the morning and rebuild it each night.  Males tend to be nomadic and are not avid web-makers.

Some (but not all) orbweavers, especially in the genus Argiope, weave a heavy “zipper” or other pattern called a stabilimentum into part of the web.  Guesses about the function of the stabilimentum are that it strengthens the web, that it allows the spider to control the tension of the strands in the web, that it gives birds a “visual” and bats an “echo” that keeps them from flying through the web, that it attracts insects by reflecting UV light, that it keeps insects from flying into the web when the spider is satiated, that it makes the rest of the web seem less conspicuous/more invisible by comparison, and that it provides a camouflaged spot for spiders to hang (head down) in the web’s center.  Not all stabilimentum look like zippers https://bugguide.net/node/view/4805https://bugguide.net/node/view/123319 (the BugLady loves the Florida Argiope Superhero spider throwing lightning).

Orbweavers will often tackle prey that is larger than they are if it gets snagged in their web.  They first paralyze it with a toxic bite, then wrap it, and later eat it.  The front two pairs of legs handle the prey while the rear two pairs manipulate the silk.  If the prey is a stinging or venomous critter, it’s “wrap first; bite later.”  They tenderize it with fluid from their mouth, and then re-ingest their digestive juices as they eat the softened prey.

Males are not avid web-makers, but for many species a web is part of the courtship ritual.  He may meet her on her web, taking care not to behave like prey (he is, after all, making her trap web vibrate) or he may spin a line (mating thread) and hang next to her web.  He typically dies after mating, even if he doesn’t inadvertently provide her with a protein meal.

In the species shown here, Mom places from several hundred to a thousand eggs in one or more spherical egg cases/cocoons that are hung from the web or hidden in tree bark or in some other crevice (that’s what those nuthatches are looking for in winter).  She guards them until she is, inevitably, killed by the cold (“And no one was with her when she died.” Charlotte’s Web).

The eggs of some species don’t hatch until spring hatch, and others hatch and make their way out of the case before winter, but it’s more common for the spiderlings to hatch and remain within the egg sac throughout winter, feeding on the yolk inside (and eventually on each other), to be called from their egg sac and balloon away in the warm air of spring.  These beauties have been around for the full spider season, it’s just that they start small and don’t get big enough to be noticeable until mid-summer/early fall.  They’re large and dramatic, and they have the right equipment to bite you, but an orbweaver’s favorite strategy is avoidance.  They’re not aggressive, but if you insist on man-handling one, it will respond appropriately.

Without further ado:

The BLACK AND YELLOW ARGIOPE/GARDEN SPIDER (Argiope aurantia) is a familiar, large (a female’s body may measure an inch-plus) spider that dwells in sunny grasslands, edges, gardens, wetlands and suburbs.  Wikipedia says its Latin name means “gilded silver-face.”  The thick zigzag stabilimentum woven into the web has given Argiopes the nickname “writing spiders.”  Webs are generally built/repaired at night, and a Black and yellow argiope will use a productive web site over and over.  Black and yellow argiope numbers have fallen dramatically and inexplicably in the BugLady’s fields in the past decade-plus.

The female makes several egg cases in fall and attaches them to the sides of the web (safe from ants, but not from birds and parasitic wasps, and not, apparently, from a bevy of inquilines (borders) either; researchers have monitored Black and yellow argiope egg cases and tallied 19 species of insects and 11 species of spider that have emerged from them).

Males are nomadic, looking for romance, but they will make a small web when they find a female.  They court by plucking the female’s web (settle down, folks – the BugLady means this literally), hoping she can differentiate suitor from prey.

BANDED GARDEN SPIDERS (Argiope trifasciata) have become more common in the fields as the Black and yellow argiope numbers have dwindled – Nature does abhor a vacuum.  Studies suggest that the webs of Banded garden spiders (and those of other diurnal orbweavers) tend to be oriented east-west, and that the position of the occupant in the center of the north side of the web, “belly” facing south, maximizes her exposure to solar heating.  Although they are as large as those of the Black and yellow argiope, the webs of Banded garden spiders may lack a stabilimentum.

The SHAMROCK ORBWEAVER (Araneus trifolium), is also called the Pumpkin spider.  One source compared the spider’s plump abdomen to the shape of a pumpkin; another attributed the name to the fact that Shamrock orbweavers are out and about around Halloween.  The family Araneidae is the third-largest spider family worldwide, and the genus Araneus is the largest spider genus, with 1,500 species known globally.

The BugLady has seen MARBLED ORBWEAVERS (Araneus marmoreus) on the forest floor on distinctly cool days into early November, pushing the limits of cold-bloodedness.  Adults spin a web and then wait, concealed in a silken hiding place, monitoring vibrations via a “signal strand” attached to the web.  When an insect gets caught in the web, the Marbled orbweaver will “process” it and carry it to its hiding place to eat it.

The CROSS ORBWEAVER (Araneus diadematus) is a non-native spider who, like the Bridge spider of previous BOTW fame, immigrated to our shores from Europe (it’s also called the European garden spider and the Diadem spider).  Like the bridge spider, it likes to hang out on buildings, especially on walls with exterior lights https://uwm.edu/field-station/cross-orbweaver-spider/.

The BugLady is calling this shy creature an ARABESQUE ORBWEAVER (Neoscona arabesca) because of the pairs of slanted, dark lines on the abdomen.  Spiders in the genus Neoscona are called “Spotted Orb Weavers.”  According to bugguide.net, the Arabesque orbweaver “stays in a retreat (usually a curled up leaf) to the side of the web during the day. At night it rests in the center of the web with the tip of the abdomen pushed through the open space in the center of the web.”

Aren’t these spiders fine!!

Here’s an article about spiders in an age of declining insect populations: https://www.theguardian.com/commentisfree/2021/aug/16/the-guardian-view-on-spiders-season-of-the-web.

Kate Redmond, The BugLady

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

Bug o’the Week – Black Witch Moth

Howdy, BugFans,

BugFan Marjie sent some “what-is-it?” pictures recently, of a lunker moth perched on one of her outbuildings.  The BugLady didn’t need to hit the books to ID this one, it’s been on her “Most Wanted” list ever since she saw its picture in Holland’s The Moth Book when she was a kid, the better part of seven decades ago.

Black Witch moths (Ascalapha odorata) are members of the moth family Erebidae (Erebus is Greek for “from the darkness.”).  They were formerly with the family Noctuidae, and they are the only members of their genus.  In all the references that the BugLady looked at – and there are many, because along with the photo site hits, local newspapers often pick up the story when a Black Witch moth comes to town – she didn’t find any explanation of the species name odorata, which is Latin for “scented, having an odor.”

Marjie’s moth was pretty worn out, which is not surprising considering how far it was from home.  Its normal range is northern South America, Central America, Mexico, and the Caribbean, but it migrates/strays both north and south from there.  Black Witch moths have been found throughout North America as far north as Alaska, Churchill, and Newfoundland, and in South America as far south as Argentina, and they have traveled to Bermuda and Africa.

There are breeding populations in Los Angeles, Hawaii, and in far-southern Texas and Florida.  Scioto County, in southern Ohio, is their northernmost “breeding record” – a newly emerged moth was found there, but whether it was the result of “boy meets girl” or of an already-gravid female winging her way to Ohio is unknown.

With a wingspan of five to seven inches and a more aerodynamic design than similarly sized Giant silk moths like the Cecropia and the Luna, Black Witch moths are strong flyers that are often described as bat-like.  They fly at night, high and fast, and minor obstacles like the Gulf of Mexico don’t deter them – they are regulars on ships and off-shore oil rigs.  According to one source, a Black Witch moth can fly from the Rio Grande to Maine in three weeks.

They tend to migrate during Mexico’s rainy season, from mid-summer until early fall, and according to PJ Liesch at the UW Madison Department of Entomology’s Insect Diagnostic Lab, Wisconsin’s annual records often follow a hurricane or a fluctuation of the jet stream, and 2021 has already seen more records than usual.  Writing on the website Texas Entomology, Mike Quinn says that an observer “reported seeing hundreds of Black Witches within the eye of Hurricane Claudette when it made landfall along the middle Texas coast at Port O’Connor on July 15, 2003. While [he] observed none before the hurricane, hundreds, perhaps thousands were reported in and around Port O’Connor by many observers immediately after the storm passed.”

Adult females have a lacy-looking line running diagonally across the upper side of their wings, and both males and females have eyespots https://bugguide.net/node/view/664388/bgimage https://bugguide.net/node/view/1307361/bgimage, and males https://bugguide.net/node/view/663495/bgimage.

https://bugguide.net/node/view/1405961/bgimage

Black Witch caterpillars https://bugguide.net/node/view/1705558/bgimage are not super-picky food specialists; they feed nocturnally on the leaves of a number of genera of trees and shrubs in the pea/legume family, especially Acacias, and including Kentucky coffee tree and locust, and they hide in bark crevices by day.  Adults nectar at flowers and sip tree sap, and they will come to the standard moth bait – a mixture of fermented fruit and beer, spread on a tree trunk.  Bats, spiders, small rodents and a few species of birds eat them; one observer watched an ambitious Purple Martin feeding one to its nestling.

So, what’s in it for animals that undertake such extreme migrations – migrations that take them far from their caterpillar host plants and from potential mates?  This kind of journey offers an opportunity for a species with the strength and the wanderlust to expand its range if it does happen upon favorable habitat.  With Climate Change, suitable habitat for these moths may shift northward, but it’s unlikely that, all other things being equal, the Black Witch caterpillar or pupa could ever survive a northern winter.  For most of the migrants, it’s a dead end.

BLACK WITCH MOTH – THE LEGEND

Mike Quinn calls it “the largest moth, if not the largest insect, north of Mexico,” so it’s not surprising that it has collected many names and that it has a place in the folklore of its homelands.  It is variously associated with death (“mariposa de la muerte,”), restless souls, bad luck, good luck (especially with money), baldness, and blindness.  In Hawaii, it is said to be the soul of someone recently dead, coming say good-bye.

Like Marjie’s moth, a good many Black Witch sightings are of moths sheltering during the day on (or even in) buildings, carports, or under eaves.  The Mayan name for the Black Witch is X-mahan-nah, which means “House-borrower,” or “Habit of borrowing houses,” or “May I borrow your house?”

For more information, see http://jimmccormac.blogspot.com/2012/10/black-witch-spawned-in-ohio.html and http://texasento.net/witch.htm.

Thanks, Marjie.  Wow!!

And when the BugLady says “Go outside, look at bugs,” remember that you could be lucky enough to find one of these giant moths.

The BugLady

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

Bug o’the Week – Argus Tortoise Beetle

Greetings, BugFans,

The BugLady’s first thought when she glanced at this beetle was that it was a Swamp milkweed leaf beetle (which, for perching purposes, doesn’t restrict itself to swamp milkweed).  Note to self – always look twice.  Although their markings are similar, this beetle is not as “leggy” as the SMLB, and so it seems to sit closer to the substrate.

Every few years, she finds a new (to her) species of tortoise beetle – we have visited them in the form of Mottled, Horsemint, and Thistle tortoise beetles – and while the adults are interesting, it’s the larvae that blow her away.  Fecal shields? Faeciforks?

Argus tortoise beetles (Chelymorpha cassidea) are in the huge leaf beetle family Chrysomelidae.  “Chelymorpha” means “turtle/tortoise-form,” and “cassid” means “helmet.”  According to Wikipedia, “The name Argus comes from the mythical Greek giant Argus Panoptes, who was sometimes depicted with 100 eyes, because the beetle is able to stretch out its red head beyond its pronotum [the front end of its thorax], as if it were a single red eye.”  Maybe a little poetic license going on, there https://bugguide.net/node/view/1286837/bgimage.

At about one- third of an inch long, it is one of the larger Chrysomelids, and it comes in various shades of orange, with heavier or lighter spotting https://bugguide.net/node/view/1608007/bgimagehttps://bugguide.net/node/view/1456941/bgimage, and https://bugguide.net/node/view/274124/bgimage, and newly emerged beetles are pale for a few days until their color develops https://bugguide.net/node/view/1080775/bgimage.  The edges of the thorax and abdomen sweep out a little, like a tiny skirt, giving the adult a suction-cup-like appearance and protecting its underpinnings from ants.  The books say that its head slants backward, which we usually can’t see because it’s hidden under the prothorax.

Females lay eggs in clusters on the leaves of host plants, members of the bindweed family Convolvulaceae https://bugguide.net/node/view/285461.  The larvae https://bugguide.net/node/view/676256/bgimage feed on the leaves gregariously for a while https://bugguide.net/node/view/274128 before going their separate ways.  A few sources say that they drop down and overwinter on the ground as pupae, but others show pupal cases on green leaves https://bugguide.net/node/view/299697 and say that they emerge in about 10 days and overwinter as adults.

An alternate common name is the Milkweed tortoise beetle, though they don’t feed on milkweed (in 1887, an entomologist named Lintner referred to them as a “milkweed beetle with bad habits”).  The bindweed family includes some domesticated species like morning glories and sweet potatoes, so this is a beetle that is on our radar.  Some sources say that it can do damage to the plant, and others say that the plants recover readily unless they are seedlings.  There are historical records of the Argus tortoise beetle on raspberry, blackberry, rose, and peas, too, but the beetles may simply have been enjoying the view.

Morning glory, hedge bindweed, and field bindweed leaves discourage grazing by manufacturing poisonous alkaloids that the Argus tortoise beetle sequesters in its body to protect itself, in turn, against predators (that’s why the beetle can get away with its eye-catching orange and black coloration).  Not 100% successfully, though – the beetle has several egg and larval parasites, and in an article published in 1889, Frank Hurlbut Chittenden wrote that “The Biological Survey has found the Argus tortoise beetle in the stomachs of 14 species of birds , most often in those of the starling ( Sturnus vulgaris ).

Brief botanical aside: Field and Hedge bindweeds are lovely, white/pale pink-flowered wild morning glories of edges and grasslands whose slender vines sprawl on sturdier plants.  They’re not native.  The problem is their root system, which is massive, with deep taproots and with rhizomes that may extend eight or more feet from the plant.  So, while the delicate vine and leaves climb over sturdier plants, robbing them of sunshine, the roots are hogging the water, and a small piece of root thrown up by a plow can grow into a new plant.  Although its dietary attentions do stray, the Argus tortoise beetle is being viewed as a biological control for bindweeds.

The cool thing about the Argus tortoise beetle is the way its larvae protect themselves.  Some insects distance themselves from their droppings (frass) because predators and parasites can track them by its odor.  Not so the tortoise beetle.  Like other tortoise beetles, the Argus tortoise beetle larva embraces its poop, saving it and fashioning it into a fecal shield, a tiny “umbrella” of frass impaled on the forked tip of its abdomen (faecifork).  This it waves around or shelters under when it feels threatened, providing its predators a “what the heck!!!” moment.  https://bugguide.net/node/view/567526 https://bugguide.net/node/view/676255/bgimage.

Brief excretory aside: The frass of skipper butterfly caterpillars, studied by a scientist who calls herself an “Evolutionary faecologist,” is expelled under pressure, like a tiny cannonball.  One blogger calls it “ballistic pooping.”  The frass pellet of the Silver-spotted Skipper may land 38 body lengths away https://www.sciencemag.org/news/2003/03/frass-flies.

Adults defend themselves in classic Leaf beetle fashion – they drop down and, says Chittenden “play possum,” and for that reason do not very often find their way into the collecting net.

When she’s researching insects, the BugLady takes note of the hits, both sacred and profane.  Lots of photography sites for this beetle, and FYI, Walmart sells a handsome Argus tortoise beetle poster.

Kate Redmond, The BugLady

Bug o’the Week – Abbott’s Sphinx Moth

Greetings BugFans,

BugFan Kine sent the BugLady some “what-is-it?” pictures of a few very hungry caterpillars on Virginia creeper, taken by her sister, Honorary BugFan Abett.  The BugLady had seen an adult Abbott’s sphinx moth, but she’s never seen this wonderful caterpillar (despite the fact that she had an out-building at her old house that was being engulfed by a mass of kudzu-like wild grape).  What a cool moth!

First of all, the family tree.  They are in the Sphinx moth family Sphingidae, a diverse bunch of 124 species in North America (1450 worldwide) that range from the clear-winged moths now gracing wild bergamot in the prairie https://bugguide.net/node/view/1451847/bgimage, to the elegant White-lined sphinx https://bugguide.net/node/view/1477718/bgimage, to the stunning, non-native Elephant sphinx https://bugguide.net/node/view/936759/bgimage, to lunkers like the Five-spotted Hawk moth https://bugguide.net/node/view/1891122/bgimage, whose caterpillar, the Tomato hornworm, is far better known than the adult. They are stocky moths, produced by stocky caterpillars (or vice versa).

Adult Sphinx/Hawk moths feed by hovering in front of a flower (like the hummingbirds that people mistake them for) and unfurling their long proboscis to reach down into it https://bugguide.net/node/view/1045011/bgimage.  Many add a behavior called “side slipping” or “swing-hovering,” in which they move from side to side while hovering; scientists think this helps them avoid predators that are lurking in the flowers.  They are important pollinators.

Sphinx moth caterpillars are called hornworms because of the horn they sport at their rear https://bugguide.net/node/view/1458120/bgimage, at least in their early days.  The horn is shed as the caterpillar matures (hard to tuck into a pupal case while wearing that), leaving it with a “button” on its rump in its last instar (an instar is the eating stage between molting stages).  Caterpillars of many species of sphinx moths feed on toxic leaves, and they either sequester the toxins in special organs within their bodies, or they are able to excrete them quickly.

The ABBOTT’S SPHINX (Sphecodina abbottii) is found in fields, woodlands, and woodland edges from the Great Plains to the Atlantic.  It has a wingspan of two to almost three inches, and its caterpillar may grow even longer.  The adult’s brindle patterning allows it to blend into tree bark https://bugguide.net/node/view/1462455/bgimage, and the scales on the upturned tip of its abdomen resemble a broken twig https://bugguide.net/node/view/55214/bgimage.  The BugLady usually routes people to bugguide.net for pictures, but – Wow – look at this spectacular shot http://ottawa.moths.ca/sphingidae/pages/07870-sphecodina-abbottii-A.html!

Abbott’s sphinxes are bumble bee mimics, even buzzing as they feed.  Jim Sogaard, in Moths and Caterpillars of the North Woods, tells us that they get nutrients from “flowers, mud, dung, carrion, and tree sap flows.”

The caterpillar starts out green, with a small horn https://bugguide.net/node/view/422561/bgimage and then becomes icy green with an orange knob https://bugguide.net/node/view/1325390/bgimage.  Later it turns either a mottled brown https://bugguide.net/node/view/954255/bgimage, which matches the woody vines of its food plants (wild grape, Virginia Creeper, and porcelainberry), or rust with green “saddles” across its back https://bugguide.net/node/view/1486385/bgimage that are said to look like a bunch of grapes.  According to Sogaard, the “brown form feeds at night, resting on the woody vines during the day.  The green form feeds by day and night, resting closer to the foliage.”

The horn eventually disappears, replaced by a dark knob that looks startlingly like a vertebrate’s eye https://bugguide.net/node/view/954257/bgimage, the Abbott Sphinx’s nod to the snake-head defense.

If a caterpillar is disturbed, it writhes around and tries to bite its tormentor.  In his blog The Backyard Anthropology Project, Tim Eisele describes holding a caterpillar, “Handling it was a bit disturbing. Imagine picking up a raw sausage, and then having it suddenly thrash violently from side to side……”  In a different blog post he says that “In addition to pretending to be a snake, it also lashed back and forth fairly violently when handled, while making kind of a “bbbrrrttt” sound by shooting air out of its breathing spiracles.

They overwinter as pupae https://bugguide.net/node/view/958421/bgimage in underground cells.  There are two generations per year in the south and only one here in God’s Country, where the adults fly in June and July.

Who was Abbott?  John Abbott (1751 – 1840) (you can find it spelled with one or two “t’s”) was a London-born naturalist who came to America in 1773.  He was a gifted artist who specialized in insects, illustrating them in all life stages.  Along with 3,000 detailed paintings of insects https://en.wikipedia.org/wiki/John_Abbot_(entomologist)#/media/File:Abbotv1tab01AA.jpghttps://en.wikipedia.org/wiki/John_Abbot_(entomologist)#/media/File:AbbotV1Tab02A.jpg, he also drew plants and birds.  According to an article in the New Georgia Encyclopedia, “Abbot’s meticulous illustrations and careful writing chronicle the habitats, life cycles, behaviors, and migratory patterns of numerous species. He also advances theories concerning the relationship between predator and prey. His work enabled others to classify closely related species, several of which were named according to Linnaean classification from Abbot’s specimens and drawings. Naturalist and evolutionary theorist Charles Darwin studied Abbot’s work prior to his own exploration of the New World.”

Kate Redmond, The BugLady

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

Bug o’the Week – Prince Baskettail Dragonfly

Greetings, BugFans,

The BugLady finds this wonderful dragonfly cruising tirelessly over cattails at the edges of lakes or patrolling long stretches of the Milwaukee River about six feet above the surface.  She takes a lot of Hail Mary shots, and this is the best she’s done (so far).

Like their smaller cousins (Beaverpond, Spiny, and Common Baskettails), Prince Baskettails are in the Emerald family Corduliidae and the genus Epitheca (from the Greek “epi “above, upon” and theca “pouch, basket, receptacle.”  Unlike other odonates, which oviposit by inserting an egg into a slit they cut in vegetation or by tapping the water with their abdomen to release the eggs within, baskettails large and small fly around with a clump of eggs at the tip of their abdomen.  These they drop into the water, either all at once, or by flying inches above the surface, dragging and snagging the egg mass on aquatic vegetation.  The glob of eggs reacts like those kids’ toys that instruct “Just add water;” the strand swells and uncoils, and it may reach 20” long and enclose as many as 1,000 eggs.

While the other baskettails measure about 2” or less, the Prince Baskettail (Epitheca princeps) is 2 ¼” to 3 ¼” long (darner-sized) – the largest baskettail and the largest member of its family.  It’s slim-bodied, with three dark spots on each wing (some, especially in the South, are larger and spottier https://bugguide.net/node/view/1351143/bgimage https://bugguide.net/node/view/1078959/bgimage).  Mature males have the bright green eyes that are characteristic of their family https://bugguide.net/node/view/398259/bgimage.  The only dragonfly you might confuse it with is the female Twelve-spotted Skimmer, which is shorter and has a heavier body and a pale line running along each side of its abdomen https://bugguide.net/node/view/1959162/bgimage.

Adults prey on small, flying insects, often hunting for mayflies high above the trees, and they may form feeding swarms at the end of the day.  Though they are large and feisty, they are not quite at the top of the food chain – here’s a Dragonhunter with a Prince Baskettail https://www.uwgb.edu/biodiversity/econotes/2007/dragonhunter.htm.  The large https://bugguide.net/node/view/935963/bgimage and spiny naiads (immatures) nab underwater critters with their extendable mouthparts.

Male Prince Baskettails patrol a large territory, as do some females when they’re looking for a place to oviposit.  Naiads hatch in a few weeks, using a hard bump on their heads to break out of the egg.  They may live in the water for a year or two before emerging, spending their final winter as naiads in deep water where temperatures are more constant.  The half-hour that it takes for them to emerge from the water, pull out of their exoskeleton, and lengthen and harden their wings for flight is a dangerous one, and one source said that only 1% of the naiads achieve adulthood.

Here’s a series of pictures of a Prince Baskettail emerging – https://bugguide.net/node/view/457838/bgimage and a picture of the exuvia (shed skin) https://bugguide.net/node/view/1442425/bgimage.

They rarely perch, and when they do, they hang vertically from a twig, and they often curve their abdomen https://bugguide.net/node/view/1675349/bgimage). The BugLady has never seen a perched Prince Baskettail (unless, of course, she glanced at one and dismissed it as a Twelve-spotted Skimmer), but she read that they are more likely to be perched on cloudy days.

On another topic completely, the BugLady is offering this without comment.  There is a similar movement in the bird world https://www.smithsonianmag.com/smart-news/these-moths-will-be-renamed-stop-use-ethnic-slur-180978151/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=20210712-daily-responsive&spMailingID=45289685&spUserID=ODg4Mzc3MzY0MTUyS0&spJobID=2043035771&spReportId=MjA0MzAzNTc3MQS2.  Who says we don’t do cutting-edge entomology here!

Kate Redmond, The BugLady

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

Bug o’the Week – Red-blue Checkered beetle

Greetings, BugFans,

The BugLady is always amazed at how masses of Coreopsis flowers paint the Riveredge prairies gold in June, and she’s equally amazed at how few of them are entertaining insects.  The books say that that Coreopsis is visited by a number of small, native bees, plus some butterflies and beetles, but she rarely sees much action on the flowers (sometimes a camouflaged crab spider waiting for incoming pollinators).  Which is why this Red-blue checkered beetle was a pleasant (and colorful) surprise.

Fun facts about Coreopsis:

  • Members of some Great Plains tribes boiled Coreopsis flowers for a few minutes to make a beverage that was red.  Pregnant women in one tribe drank a tea made from Coreopsis plants to increase their chances of bearing a girl child.

Checkered beetles are in the family Cleridae.  We visited the Clerids seven years ago in the form of a cute little beetle that the BugLady found on a wild sunflower – see that episode for general info about the family https://uwm.edu/field-station/checkered-beetle/.  There are about 300 species of Checkered beetles in North America; many are colorful, and they lead diverse lifestyles, and some are biological controls of bark beetles.

 

Red-blue Checkered beetles (Trichodes nuttalli) (aka Nuttall’s shaggy beetle) are found east-of-the-Rockies https://bugguide.net/node/view/3405/data in grasslands and edges.  They’re about 1/3” long, and in Beetles of Eastern North America, Evans describes them as elongate, robust, sparsely clothed in light-colored setae, metallic blue or green, antennae and mouthparts brown, and bicolored elytra” https://bugguide.net/node/view/213154/bgimage and https://bugguide.net/node/view/1105035/bgimage.

One of the really basic questions we can ask about an insect (or any animal) is “What does it eat?”  On this subject, the reports on the RBCB are contradictory.  Reputable sources say that the adults eat pollen from a variety of grassland, edge, and wetland flowers and are not predaceous – or that they feed on pollen and on small insects they find on the flower tops.  Yes, the larvae are carnivores.  But – do they feed only on the eggs and nymphs of the Sprinkled grasshopper https://bugguide.net/node/view/619072/bgimage, as some scholarly publications attest?  Or, as other, equally scholarly sources say, do RBCB eggs stick to foraging bees and wasps and get taken back to their nests, where they hatch and feed on the bee larvae in the nest (and maybe on cached pollen, too)?  Or do the eggs hatch on the flower and the larvae grab hold and ride back to wasp and bee nests?  As several authors noted – this species needs more study.

RBCBs are beetles of early summer.  Eggs are laid on flowers where the adults feed (or, if you’re in the Grasshopper Camp, in crevices on the ground).  The larvae may overwinter as larvae, pupae, or pre-pupae.

Fun Facts about RBCBs:

  • If you need a (dead) RBCB for your collection, several online stores will sell you one for about $3.00.

  • According to the journal Biophilately, the RBCB was one of four insects illustrated in a block of “Garden Insects” stamps issued in the Seychelles in 2014.

Author Jeff Mitton poses some interesting questions about RBCBs in his article in the Colorado Arts and Sciences Magazine https://www.colorado.edu/asmagazine-archive/node/1017.  First of all, considering its coloration [and its daytime feeding habits], it’s logical that the beetle enjoys some chemical defenses, but there’s no information Yea or Nay.

Second, this beetle a pretty much of a generalist, both in the variety of flowers the adults feed on and in the variety of hymenopterans the eggs/larvae hitchhike on.  But [and Mitton is in the Bees and Wasps Camp] it’s one of a number of insects whose continued existence depends on the behavior of another insect – in this case, the bee that unwittingly carries it home.  It’s a big gamble.  He suggests that if its hosts became more fastid13 – red-blue checkered beetle13ious and groomed the beetle eggs/larvae off their bodies, or if they were able to recognize the larvae in the hive and dispose of them, or if the hosts became extinct, the beetle would soon be on the road to extinction itself.

Speaking of beetles and “extinct,” here’s an interesting blog post on ladybugs (thanks to BugFan Molly) – https://prairieecologist.com/2021/06/19/losing-ladybugs/.  Be sure to click on the “Ladybugs of South Dakota” poster.

Kate Redmond, The BugLady

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