Tag: bug

Bug o’the Week – Caddisfly revisited

Bug o’the Week
by Kate Redmond

Caddisfly revisited

Greetings, BugFans,

The BugLady is suffering from the February Doldrums in January – this is a massaged version of a BOTW that was originally posted in 2009, with some new words and new pictures.

“What’s in a name?  A rose by any other name would smell as sweet.”  What indeed?  The BugLady will get back to that.

Caddisflies, in the Order Trichoptera (“hairy wings”), are famous for the cases built for protection by their soft-bodied larvae (the only natural “armor” they possess is located on their head, thorax and legs) and for the larvae’s ability to produce silk thread via a silk gland in their lower lip.  They use silk to “glue” materials together to construct the case, to net some food, and to modify the case before they pupate.

Caddisfly larvae live in both running and still water; in fact, according to Elsie Klots in The New Fieldbook of Freshwater Life, they are one of four orders of insects that “have become almost wholly aquatic during their immature life.”  The larvae of one European species live in wet moss, and the larvae of another, called the Land Caddisfly (Enoicyla pusilla), are terrestrial, but they still make cases out of materials they find in the leaf litter where they live.  Female Land Caddisflies are wingless.

Many of the pond dwellers cut and assemble small bits of vegetation into portable homes.  Some “homes” are thin tubes, some get glued together “the long way,” and some resemble Lincoln-log-like chimneys made of mini-twigs, sedges or cattails custom-trimmed by the larva.  In streams or rivers, where staying in one place is a challenge, the larvae use heavier building materials like tiny pieces of gravel, or they spin a net that they glue onto a rock or into a crevice.  Unlike turtles, whose shell and body are joined, caddisflies can leave their case of sticks or stones.  Naked – deprived of their homes – they look like little wet caterpillars (to whom they are not-so-distantly related). 

Cases are open at both ends, to facilitate oxygen circulation, and in very still water, the larvae must be more active in order to make up for the lack of a current.  Caddisfly larvae are so specific about their choices of building materials that they can be classified down to family and sometimes genus, by the structure of their shelter.

The caddisflies, also called sedge-flies and rail-flies (and “fish food”), are a big order, with more than 15,000 species worldwide.  North America boasts around 1,500 species of Tri-cops (as they are known familiarly), and not surprisingly for such a large group, their larvae indulge in a wide variety of feeding methods.  There are predators and scavengers.  There are “shredders” that perform the valuable service of turning big pieces of vegetation into little ones, thereby setting the table for even smaller organisms.  Some net-spinners are “collectors” that let the current deliver their meals (bits of organic material) “carry-out” (some net-spinners can produce a sound by rubbing a front leg against the underside of their head).  Finally, there are “scrapers,” grazing on algae and other tiny organic particles stuck to underwater surfaces.  As adults, with mouthparts that are described as “sponge like,” they ingest only liquids, and many species don’t feed as adults.

Adult caddisflies resemble slim, very long-antennaed moths; they tent their wings above their abdomens (making them look triangular from the rear), and their wings are covered with tiny hairs.  Females of some species actually climb under water to lay their eggs, protected from getting soaked by a thin layer of air trapped in that dense covering of hairs.  According to Eaton and Kaufman in the Field Guide to Insects of North America, fly-tiers (or tie-flyers) work hard to replicate caddisflies with their lures.  Exceptionally sensitive to pollution, the presence of caddisflies signals good water quality.  And, with a little luck, trout. 

Once, when the BugLady gave a presentation about Pond Life to third graders, a child asked where the caddisfly got its name.  The BugLady did not know, but she loves to research the etymology of entomology, so she promised to find out, and here is what she discovered.  Back in the days of the first Queen Elizabeth (when Romeo and Juliet were obsessing about names) (and in the midst of the Little Ice Age – fascinating – look it up), itinerant peddlers roamed the world.  Those who sold ribbons, threads and yarns were called “Cadice-men” after “cadaz/caddis/caddice” – words that had come to refer to worsted yarn.  Cadice-men displayed their wares by attaching samples of threads and yarns to their coats.  In his wonderful A Guide to Common Freshwater Invertebrates of North America, J. Reese Voshell, Jr. says that the larva’s ability to glue pieces of material together to make its case was reminiscent of how a Cadice-man covered his jacket with pieces of textile.  Alternatively, it may refer to the fringe on the adults’ wings.  Was the person who named caddisflies, like the BugLady, a bug-loving history-geek?

If you search online, you can find jewelry made out of caddisfly cases – entrepreneurs supply caddisfly larvae with a variety of bling, and the larvae incorporate it into their cases. 

Kate Redmond, The BugLady

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

Bug o’the Week – Cereal bug

Bug o’the Week
by Kate Redmond

Cereal bug

Greetings, BugFans,

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

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

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

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

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

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

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

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

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

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

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

Kate Redmond, The BugLady

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

Bug o’the Week – Moths – Four Very Short Stories

Bug o’the Week
by Kate Redmond

Moths – Four Very Short Stories

Greetings, BugFans,

Everybody likes butterflies (the BugLady would not like to meet the person who dislikes butterflies).  But, in the order Lepidoptera, butterflies are just the tip of the iceberg – the heavy lifting is done by moths.  There are in the neighborhood of 180,000 species of Lepidoptera worldwide (“10% of the total described species of living organisms,” says Wikipedia), and about nine-tenths of them are moths.  Only around 700 of North America’s 12,000 species of Lepidoptera are butterflies.

Moths often languish in the BugLady’s picture files because: A) They can be tough to identify; and B) Most are not notorious enough to have drawn much attention to themselves, so their biographies are hard to find and are more like short stories.

Three of today’s four moths are in the family Geometridae – the “earth-measurers” or “loopers” – so-named for the gait of their caterpillars, the inchworms.  They are slim, well-camouflaged caterpillars with long abdominal segments, but with fewer and reduced abdominal prolegs (the fleshy, unjointed “helper” legs – the six real legs are on the thorax).  Having one set of prolegs toward the front of the abdomen and one set at the rear leaves them with no visible means of support in the middle, so they “inch” – move their front end forward and then hike the rear end up to follow it, measuring the earth as they go.  

About the Geometrids, Wagner, in Caterpillars of Eastern North America, says “Whether measured in terms of abundance or biomass, loopers are among the most important forest lepidopterans in Eastern North America.  They are an especially important component of the spring caterpillar fauna of deciduous forests, where they are a staple in the diets of many forest-nesting birds.” 

The NORTHERN PETROPHORA MOTH(Petrophora subaequaria)

The BugLady found this pretty moth in May at a small, acid bog that she frequents.  The Northern Petrophora moth is a Northeastern moth that is close to the west edge of its range in Wisconsin.  Caterpillars https://bugguide.net/node/view/1503546/bgimage are abroad throughout summer and are oligophagous (they feed on a variety of related plants) – look for them on ferns, including bracken fern.  The caterpillars have been described as “strong jumpers.”  

The COMMON METARRANTHIS (Metarranthis hypochraria)

The caterpillars feed in early summer on a number of trees and shrubs, especially in the genus Prunus (cherries, apples, and plums) and are stick mimics, but mature caterpillars are hard to find.  Wagner speculates that they may move down from the leaves onto the trunk or into the litter by day.  He also says that (of course) “the taxonomy of the group is in need of review.”  Many adults in this genus fly during the day and they often perch on the ground, cryptic against the fallen leaves.     

The THREE-SPOTTED FILLIP (Heterophleps triguttaria)

The BugLady found this small (3/4” wingspan), distinctly-marked moth at the same bog as the Petrophora moth.  It’s found throughout the spring and summer in wet woodlands and marshes from Colorado to Ontario to Quebec to North Carolina, and according to the “Moths of North Carolina” page on the NC Parks website, the majority of its other genus members live in India and China. 

It’s monophagous – it had long been thought that the caterpillar host plant was maple, but caterpillars that were fed maple leaves in the lab wouldn’t eat them, and it turned out that the caterpillars host is Clearweed, a kind of nettle. 

So – what is a “fillip?”  There are several, very diverse meanings, but an archaic one seems to fit in this context, “a movement made by bending the last joint of the finger against the thumb and suddenly releasing it; a flick of the finger.”  “To propel a small object with a flick of the finger.”  “Fillip is considered a phonetic imitation of the sharp release of a curled-up finger aimed to strike something.”  And it turns out that, according to the NC Parks website, “When disturbed the larvae form a tight coil and are known to hurl their frass pellets.”  

And the MORBID OWLET (Chytolita morbidalis) 

The Morbid Owlet is in the family Erebidae and the subfamily Herminiinae, the litter moths, some of whose caterpillars feed on live leaves, while others feed on algae, lichens, fungi, dung, decomposing vegetation or insects, organic stuff they find around animal nests.  Wagner describes them as lethargic caterpillars that avoid the light and that play dead when bothered.  Bugguide.net says that “morbidalis” comes from “morbus,” meaning “disease” and probably refers to the “sickly pale color” of the moth.  The “snout” protruding from the head is formed by the “labial palps,” which have a sensory function in feeding.

Morbid Owlet caterpillars eat dead leaves (they’re detritivores) and low vegetation like dandelions.  Wagner says that “they flatten the rear of the body in a manner that suggests a false head.”

Using her Peterson Field Guide to the Moths of Northeastern North America, the BugLady originally ID’d this moth as a Stone-winged Owlet Moth (Chytolita petrealis), but when she Googled it, it kept coming up as the Morbid Owlet (Chytolita morbidalis).  It appears that a recent taxonomic review of the genus (done after her moth book was published) lists Chytolita petrealis as a synonym of Chytolita morbidalis – basically, same species – and now the only member of its genus north of the Rio Grande.  The Stone-winged Owlet Moth form is said to be smaller and darker than the Morbid Owlet form.  Bugguide.net, whose account must also have been written before the review, lists the habitat of the Morbid Owlet as “deciduous woods and edges; generally drier or less boggy habitat than Chytolita petrealis.”   

Not so fast, says the North Carolina Parks Chytolita petrealis page.  “Chytolita petrealis is currently treated by some authorities to be a synonym of morbidalis, following determination that the type of petrealis was a morbidalis. Prior to that realization, however, the name petrealis had been applied to a distinct and much rarer species in the Southeast. The authors who sunk petrealis did not realize this so our petrealis has no name at the moment. To make things more complicated, there is another undescribed thing like it from the mountains (2-3 specimens known) whereas the petrealis that has been most widely recognized is present primarily in the Coastal Plain.”  And, it goes on to say “The majority of our records come from swamp and floodplain forests, forested shorelines, as well as peatlands and other wet forests.” 

The BugLady found it in that same acid bog as the Petrophora and the Fillip moths.  

Fun Fact about the Northern Petrophora Moth:

The species was described by 19th century British entomologist Francis Walker.  He published like crazy, shared his knowledge generously, and was respected by many of his peers.  Between 1848 and 1873, he worked at the monumental task of cataloging the insects in the collection of the British Museum, a task for which he was paid one shilling for each new species he determined and one pound for each new genus (and where he ended up describing 16,000 species).  Alas, he turned out to be a little careless/enthusiastic, sometimes assigning multiple different scientific names to specimens of the same species.  One source said that he was no worse than many other entomologists of his day – imagine doing a job like that without the kinds of communication, magnifying, and imaging tools we have today – but the huge scale he was working on multiplied his errors. 

After his death, an unsigned obituary began “More than twenty years too late for his scientific reputation, and after having done an amount of injury almost inconceivable in its immensity, Francis Walker has passed from among us.” 

Brutal!

Kate Redmond, The BugLady

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

Bug o’the Week – Saddleback Caterpillar – A Snowbird Special

Bug o’the Week
by Kate Redmond

Bug o’the Week Saddleback Caterpillar A Snowbird Special

Greetings, BugFans,

Today’s bug, the extraordinary-looking and aptly-named Saddle-backed caterpillar, is the 5th in our on-going Snowbird Special series about bugs you might see if you decide to tear yourself away from God’s Country in the winter.  The BugLady doesn’t know why one might consider that – except she’s posting this before dark because there’s a massive storm that’s raining all over her, accompanied by 20-plus mph north winds, and is delivering many inches of snow inland.  She suspects that the power will fail eventually.

Thanks to BugFan Tom in the Deep South for his pictures of this amazing caterpillar.

The Slug caterpillar family Limnacodidae has appeared in these pages before https://uwm.edu/field-station/bug-of-the-week/slug-moths-tale-two-parts/.  Limnacodidae means “snail/slug-form” and refers to its caterpillars, some of which look like space aliens, while others are limpet-shaped.  They have suckers instead of abdominal prolegs https://bugguide.net/node/view/225763/bgimage (prolegs are fleshy, unjointed “legs” that act as anchors, gripping the surface while the true legs (on the thorax) and the muscles in the body work to move it along).  Slug caterpillars exude a lubricant (not slime, like snails and slugs, but a type of liquid silk) that allows them to contact the substrate more completely and to glide/undulate through life.  Some have a smooth exterior, some are bristly, and some, like the Saddleback caterpillar, have fleshy horns decorated with hollow, stinging spines and hairs that will get your attention if you encounter one (more about that in a sec). 

Slug moths tend to be dark, sturdy, and hairy, with wide wings.  They can’t hear and they don’t feed, and they generally live for little longer than a week.  They often perch with the tip of their abdomen raised, though other kinds of moths do that, too.   

The BugLady always thinks of members of this family as belonging to the Deep South (because they have more “sting-y” things down there), but the range of the Saddle-backed caterpillar extends from Massachusetts to Florida to Texas (and points south) to Kansas, and through parts of Illinois (the BugLady saw a few maps that showed the species in far southern Wisconsin).  A number of species of Limnacodids are native to Wisconsin, including:

the Spiny oak slug https://bugguide.net/node/view/2212985/bgimage,

the Crowned slug moth https://bugguide.net/node/view/1938355/bgimage,

and the less-fancy but still lovely Shagreened slug moth https://bugguide.net/node/view/1859138/bgimage, and Skiff moth https://bugguide.net/node/view/446465/bgimage.     

Without further ado, the SADDLEBACK CATERPILLAR (Acharia stimulea).  

Adults fly in June and July in the northern parts of their range and pretty much all year Down South.  The eggs – so transparent that the tiny larvae may be seen inside https://bugguide.net/node/view/2003668/bgimage – are deposited at night in clumps of 30 to 50 on the undersides of the leaves of host plants. 

It’s not hard to find a host plant, because Saddleback Caterpillars eat the leaves of a pretty wide variety of trees, shrubs, wildflowers, grasses, garden plants and horticultural plantings.  Their only stipulation is that the leaves be smooth, not pubescent (hairy) – the rough texture of hairier leaves interferes with their ability to adhere and to move.   

Like other species of slug moths, Saddle-back caterpillars are, initially, gregarious leaf skeletonizers, nibbling at the tender surface of the underside side of a leaf and eschewing the tough leaf veins https://bugguide.net/node/view/954559/bgimage.  As they grow, they take on the whole leaf and eventually become more solitary.  Caterpillars take four or five months to mature (here’s a pretty cool shot of one that just molted https://bugguide.net/node/view/1570339/bgimage). 

About the sharp bits: 

The long, hollow spines contain a “hemolytic and vesicating venom” (a red-blood-cell-destroying and blister-raising venom) and will break away from the caterpillar and embed in whatever bumped/grabbed them (removing the spines gently and immediately with tape is highly recommended, followed by an ice pack) (and maybe an adult beverage).  Are the spines effective? 

Wagner, in Caterpillars of Eastern North America, says that, due to its size and quantity of its stinging spines, “The sting of the Saddleback Caterpillar may be the most potent of any North American caterpillar.” 

One contributor to bugguide.net wrote that “I grabbed a dead looking leaf off my small incubating Rose of Sharon in the evening. After that I don’t remember much. It was horrifying being stung by this well equipped little creature from another planet.”

A Virginia Extension Agent likened it to “getting hit by a jellyfish.”

The spines, which are part of the caterpillars’ redundant defense system, give pause to most vertebrate and invertebrate predators.  The venom can trigger intense pain, hives, migraines, GI issues, asthma, and even anaphylactic shock.  Yet they are vulnerable to tiny parasitic wasps that slip in between the spines and inject eggs into the caterpillar’s body.  The wasp larvae consume the inside of the caterpillar and then crawl outside to pupate in cocoons that look like tiny swabs https://bugguide.net/node/view/79421/bgimage.  And Tom photographed one in the clutches of the awesome nymph of a Giant Strong-nosed stink bug

They spend the winter as pre-pupae, and as they’re preparing to pupate, they intentionally expel fluids and frass from their bodies and shrink by about half.  The result is that the spines are more “concentrated” on their body surface than before.  They also release calcium oxalate (that’s the stuff that makes skunk cabbage poisonous), which forms crystals in the fabric of the cocoon and hardens it.  Spines may also be woven into the silk of the cocoon, too, and scattered around it.  Despite this, there’s still predation on the pupae.   

The Bottom Line: The moth is stunning https://bugguide.net/node/view/752824/bgimage, (and almost no one is sensitive to its hairs).  The caterpillars are cute as a button when they’re kittens https://bugguide.net/node/view/2225127/bgimage and are beautiful when they’re mature (about ¾” long).  The striking pattern of older caterpillars is thought to be aposematic (warning) coloration.  Plus, older caterpillars have a startle reaction that puts their spines at the ready.  Plus, their adhesive abilities mean that if you do bump one, it won’t just drop to the ground, encounter over – it will stick to its spot.  Plus, from the rear, their markings make a scary face https://bugguide.net/node/view/693213/bgimage.  Take the hint (and maybe don’t go barefoot, and maybe don’t grab ahold of a leaf without checking its underside). 

Special Treat – a Spun glass slug https://bugguide.net/node/view/2211409/bgimage (very young), and older https://bugguide.net/node/view/1480728/bgimage, https://bugguide.net/node/view/990165/bgimage, https://bugguide.net/node/view/9412/bgimage.

Special Thanks to the awesome folks at the University of Wisconsin Milwaukee who format the episodes and archive them on the Field Station website (and make them look good!).

Kate Redmond, The BugLady

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

Bug o’the Week – Parnassia Miner Bee – a Bee and its Flower

Bug o’the Week
by Kate Redmond

Bug o’the Week Parnassia Miner Bee a Bee and its Flower

Howdy, BugFans,

A while back, BugFan Matt asked the BugLady if she had ever photographed a small bee on a Grass-of-Parnassus flower.  Grass-of-Parnassus (not really a grass) is one of her favorite flowers (despite the fact that it shouts “Fall is coming!” every time she sees it).  She photographs it a lot in the closing days of August, and it turned out that she had seen the bee, but she hadn’t realized how special it was.

As BugFans will recall from those six weeks of mythology in high school English, Mount Parnassus was sacred to Apollo and was home to the Muses in Greek mythology.  Allegedly, cattle on Mount Parnassus grazed on the plant, and so it was promoted to honorary grass status.

Mining bees have been featured on these pages before (https://uwm.edu/field-station/bug-of-the-week/red-tailed-mining-bee/).  They are small and fuzzy and are among our earliest pollinators (the fuzz keeps them warm on chilly spring mornings).   Some are catholic in their tastes (polylectic), but many species are linked to a single, small group of related plants (oligolectic), and some zero in on only a single species (monolectic).  Many have no common name at all, but like the Parnassus miner bee, their scientific name may include a nod to their affiliated plant. 

They emerge when their host plants emerge, make tunnels a few inches deep in the ground, scoop out, waterproof, and provision chambers within them with pollen and nectar, and then install the next generation, which will overwinter underground and repeat the cycle when their flower reappears.  The various species of mining bees and their flowers span the growing season, and late summer mining bee species are most often seen on goldenrod and on members of the carrot family. 

Except the PARNASSIA MINER BEES (Andrena parnassiae), which are found only where Grass-of-Parnassus lives – calcareous fens (another name for the plant is the Fen Grass-of-Parnassus) and other wet, alkaline meadows and wetlands.  They’ve been recorded in Wisconsin, Michigan, Vermont, and North Carolina.  A journal article from the early 20th century said that the bee’s flight period went from August 25 to September 26, and that its only known Wisconsin occurrence was on the Lake Michigan bluffs in the Milwaukee suburb of Whitefish Bay, on a plant that was misidentified, due to an error in an early botany reference, as Carolina Grass of Parnassus (which is found in Florida and the Carolinas). 

The hairs on their body act as pollen collectors, too, and they have pollen baskets on their back legs.  Parnassia Miner Bees only glean pollen from Grass-of-Parnassus flowers (and they are important pollinators of it – more about that in a sec), but the flowers are also visited by other bee species, syrphid and other small flies, ichneumon wasps, butterflies, (and the BugLady found a lightning beetle checking it), and by spiders with a taste for pollinators.    

When you (or a bee) look at the flower, what do you see?  The green lines on the five petals are nectar guides, beckoning the bee to follow them to the nectar source.  But the bee also notices a ring of 15 filaments at the base of the petals (actually five sterile stamens or staminoides, each divided into three prongs), each topped with what looks like a drop of nectar, resembling the (male) stamens of the flower.  These are false nectaries that provide no nectar reward but serve to get the bee into the right vicinity – the real nectar lies at the base of the filaments. 

There are also five true stamens, each topped with a pollen-producing anther, and in the green center of the flower, the female flower parts – stigma, style and ovary (collectively called the pistil).

[Nota Bene: the BugLady learned just enough Botany in college to make it through the Botany final, and she’s been forgetting it ever since, so she has to pull up a chart on Wikipedia every time she tries to write about flowers.] 

The BugLady was wondering about the pedigree of Grass-of-Parnassus and she encountered some confusion about that.  Several reputable sites reported that it was in the Saxifrage family, but another said that there was only a very distant familial connection.  Others put it in the Staff tree family Celestraceae, and still others placed it in its own family Parnassiaceae (though it may be destined to rejoin the Celestraceae).   

OLYMPUS DIGITAL CAMERA

Putting it all together: It’s a sweet little flower that has worked out some complex strategies to spread pollen and to avoid self-fertilization.  Consider the five true stamens.  Rather than maturing all at once, only one lengthens, matures and produces pollen per day, arcing over the top of the pistil.  After the first day, its anther turns brown and the filament relaxes against the ring of petals, and another stamen grows and produces pollen.  

The pistil does not grow or become receptive to incoming pollen until after all five stamens have matured, making it impossible for the flower to self-pollinate.  Eastman, in The Book of Swamp and Bog, says that the flowers exhibit protandry – that is, the flower, which has both male and female parts, is unisexually sequenced, the male parts completing their development before the female parts start.  To put it another way, the flowers have a male phase and then a female phase.

When a bee is tempted by the beads of false nectar and orients itself to harvest some, it straddles an anther, and pollen is picked up by the hairs on its abdomen.  When it visits the next flower, pollen is brushed off, hopefully onto a flower whose female parts are ready to receive it (“xenogamy” “stranger marriage” — a flower breeding not with itself but with another).  

Bryan Pfeiffer, naturalist and blogger (“Chasing Nature”) and Grass-of-Parnassus watcher, has written some very nice entries about his experiences with both the flower and the bee – here are two – https://bryanpfeiffer.com/2021/09/06/being-with-flowers/ and https://chasingnature.substack.com/p/a-duplicitous-flower-and-its-rare#:~:text=Parnassia%20Miner%20gets%20that%20pollen,butterfly%20caterpillars%20eating%20only%20milkweeds (this one has a nice shot of a bee on the stamens).  

Xenogamy, polylectic, oligolectic, monolectic, staminoides, protandry, stamens and pistils and anthers, oh my – it’s January, time to dust off our brains.  There will be a quiz. 

Kate Redmond, The BugLady

As a bit of lagniappe, here’s a lovely video about butterflies (audio on): https://www.smithsonianmag.com/videos/ten-fun-facts-about-butterflies/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=editorial&spMailingID=49251228&spUserID=ODg4Mzc3MzY0MTUyS0&spJobID=2620068856&spReportId=MjYyMDA2ODg1NgS2

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

Bug o’the Week – Masked Hunter redo

Bug o’the Week
by Kate Redmond

Bug o’the Week Masked Hunter redo

Salutations, BugFans,

It’s the trough between Christmas and New Year’s – nothing but reruns.  This one, from 2009, has a few new words and pictures.  Party on!

Occasionally, one of the BugLady’s wee dust bunnies becomes a little more animated than the rest of them – a situation that is startling, momentarily, until she remembers the Masked Hunter (Reduvius personatus), an alien bug from Europe and Africa that is now found throughout the US.  The adult is a striking, shiny, black bug about ¾” long. The pale immature (nymph) has a sticky exterior that attracts lint and dust, earning it the nickname “dustbug,” and camouflaging or “masking” it from its predators.  One correspondent on www.whatsthatbug.com submitted a photo of a blue nymph that was living in a blue shag carpet; another referred to them as having a “tempura-like” coating.  Here’s an orange one https://bugguide.net/node/view/33323/bgimage.

Masked Hunters, in the Order Hemiptera (True Bugs), are in the Assassin bug family Reduvidae (and subfamily Reduviinae), a group of active and ambitious hunters that stalk primarily insect prey and will go after critters that are larger than they are.  They dispatch their prey by stabbing it with their short beak (rostrum) and injecting it with potent chemicals that both paralyze their catch and soften its innards so they may be slurped out. 

A different subfamily of Assassin bugs (not the Masked Hunter’s) includes bugs called “Kissing Bugs” https://bugguide.net/node/view/1968832/bgimage – the ultimate in image ambiguity. They feed on the blood of mammals, including humans, and a few are notorious disease vectors; their nickname derives from their targeting the thin skin on their victim’s face, especially the lips, often while said victim is asleep.  The debilitating and potentially fatal Chagas disease of Central and South America is spread by these Kissing bugs, which bear a family resemblance to the Masked Hunter.  There are a number of species of kissing bugs – mostly tropical, but one that gets into southern Illinois – and there are several kissing bug look-alikes on our landscape, but kissing bugs have not been recorded in Wisconsin. 

The good news is that Masked Hunters are insect-feeders, untiring consumers of bedbugs, pests that are staging a comeback in big cities everywhere thanks to the ease of world travel.  The bad news is that they are untiring and, according to some references, nearly exclusive consumers of bedbugs, and these authors suggest that if you have the predator, perhaps you should check for the prey!  Masked Hunters also live in nest colonies of Swallows, dining on small bedbug-relatives called “Swallow bugs.”  The BugLady sees Masked Hunters on early summer nights on her front porch, to which they and hundreds of other insects are attracted by the porch light, and she has read that sowbugs, lacewings, flies, carpet and grain beetles, and earwigs show up on their dinner plates, too. 

HANDLE WITH CARE (or preferably not at all)!!!  Masked Hunters and their relatives are not aggressive toward humans (and most do not spread disease), but they can defend themselves effectively if manhandled. The same beak that is so lethal to their prey can deliver a poke that is described by Eaton and Kaufman in their Field Guide to Insects of North America as “excruciating” and by other references as “like a snakebite,” and “painful enough to cause immediate faintness and vomiting” and as resulting in longer-term swelling, blood blisters and irritation.  The “Kissing Bug Scare of 1899” (True story! Google it!) was apparently caused when these guys (or their relatives, the Black Corsairs https://bugguide.net/node/view/1809856/bgimage, sources disagree) experienced a population boom in the northeast, entered houses in large numbers, and inflicted bites as people brushed them away from their faces. 

When they’re not feeding, assassin bugs bend their heads slightly downward, resting the beak/rostrum in a short, ridged grove between their forelegs.  They can produce sound by rubbing the beak-tip across these ridges.  Stridulation.

Kate Redmond, The BugLady

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

Bug o’the Week – The 12 (or 13) Bugs of Christmas

Bug o’the Week
by Kate Redmond

Bug o’the Week The 12 (or 13) Bugs of Christmas

Greetings of the Season, BugFans,

(13 bugs, because once she’s got her selection down to 13, the BugLady just can’t cut one more!)

A Cheery Thought for the Holidays, the average home contains between 32 and 211 species of arthropods (with the lower numbers at higher Latitudes and higher numbers as you head south past the Mason-Dixon Line).  So, while the BugLady is celebrating The 12 (or 13) Bugs of Christmas, most BugFans could rustle up at least that many under their own roofs.  Whether you see them or not, all kinds of invertebrates coexist with us daily, mostly staying under our radar until we surprise each other with a quick glimpse.

Here are a baker’s dozen of the bugs that the BugLady saw in 2023.

BALTIMORE CHECKERSPOT CATERPILLAR – According to one researcher, caterpillars are “essentially bags of macerated leaves.”  What kind of leaves does a Baltimore Checkerspot caterpillar macerate?  The eggs are laid in the second half of summer on, historically, White turtlehead, a native wildflower, and more recently, Lance-leaved plantain has been added as a host plant.  Both plants contain chemicals that make the caterpillars distasteful to birds, though the turtlehead has higher concentrations of them.  The butterflies have adapted to use an introduced plant, but the caterpillars don’t do as well on it (the BugLady has also seen them on goldenrod).  Half-grown caterpillars overwinter, and when they emerge to finish eating/maturing in spring, the turtlehead isn’t up yet, so they eat the leaves of White ash and a few spring wildflowers.   

LEAFCUTTER BEE ON PITCHER PLANT – Bumble bees and Honey bees are listed as the main pollinators of Purple pitcher plants, along with a flesh fly called the Pitcher plant fly (Fletcherimyia fletcheri), a pitcher plant specialist that contacts the pollen when it shelters in the flowers.  But it looks like this Leafcutter bee is having a go at it. 

SEVEN-SPOTTED LADYBUGS had a moment this year; for a while in early summer, they were the only ladybug/lady beetle that the BugLady saw.  Like the Asian multicolored lady beetle, they were introduced from Eurasia on purpose in the ‘70’s to eat aphids.  But (and the BugLady is getting tired of singing this chorus) they made themselves at home beyond the agricultural fields and set about out-competing our native species. 

An Aside: Lots of people buy sacks of ladybugs to use as pest control in their gardens.  The BugLady did a little poking around to see which species were being sold.  Some sites readily named a native species, but most did not specify.  Several sites warned that unless you are buying lab-grown beetles, your purchase is probably native beetles scooped up during hibernation, thus posing another threat to their numbers

SOLDIER FLY LARVA – The BugLady is familiar with Soldier fly larvae in the form of the flattened, spindle-shaped larvae https://bugguide.net/node/view/1800040/bgimage that float at the surface of still waters, breathing through a “tailpipe” and locomoting with languid undulations.  So she was pretty surprised when she saw this one trucking handily across a rock in a quiet bay along the edge of the Milwaukee River.  It appears to have been crawling through/living in the mud. 

COMMON WOOD NYMPH – And an out-of-focus Common Wood Nymph at that.  The BugLady has a long lens, and her arms weren’t quite long enough to get the butterfly far enough away to focus this shot.  And it’s really hard to change lenses with a butterfly sitting on your finger.

FALSE MILKWEED BUG – Milkweed bugs are seed bugs that live on milkweeds, but if you’ve ever seen a milkweed bug that was not on a milkweed (usually on an ox-eye sunflower), it was probably a False milkweed bug.  They’re so easily mistaken for a Small milkweed bug that one bugguide.net commentator said that all of their pictures of Small milkweed bugs should be reviewed.  Here’s a Small milkweed bug with a single black heart on its back bracketed by an almost-complete orange “X” https://bugguide.net/node/view/2279630/bgimage; and here’s the False milkweed bug, whose markings look (to the BugLady) like an almost complete “X” surrounding two, nesting black hearts https://bugguide.net/node/view/35141.  One thoughtful blogger pointed out that although it looks like a distasteful milkweed feeder, it’s not thought to be toxic.  He wondered if this is a case of mimicry, or if the bug once fed on milkweed, developed protective (aposematic) coloration, and then changed its diet?

LARGE EMPTY OAK APPLE GALL – That’s really its name, but “empty” refers to the less-than-solid interior of the gall https://bugguide.net/node/view/54459 (which was made by this tiny gall wasp https://bugguide.net/node/view/260612).  Galls are formed (generically) when a chemical introduced by the female bug that lays the egg, by the egg itself, and later by the larva, causes the plant to grow extra, sometimes bizarre, tissue at that spot.  The gall maker lives in/eats the inside of the gall until it emerges as an adult.  Some galls are made by mites – same principle.

SYRPHID FLIES are pretty hardy.  Some species appear on the pussy willows and dandelions of early spring, and others nectar on the last dandelions of late fall.  This one was photographed on November 17, on a sunny and breezy day with temperatures in the low 40’s, 12 feet off the ground, resting on the BugLady’s “go-bag” (the bag of extra clothes she carries up onto the hawk tower to deal with the wind chill).

WASP WITH SPIDER – The BugLady saw a little flurry of activity near an orbweaver web on her porch one day, but she got it backward.  At first she thought that the spider had snagged the wasp (a Common blue mud dauber), but it was the wasp that hopped up onto the railing with its prey, part of the spider collection she will put together for an eventual larva.

SIX-SPOTTED TIGER BEETLES grace these collections perhaps more than any other insect, because – why ever not!

JUST-EMERGED DAMSELFLY – This damselfly was so recently emerged (possibly from the shed skin nearby) that its wings are still longer than its abdomen (basic survival theory says that you put a rush on developing the parts you might need most).  Will a few of the aphids on the pondweed leaves be its first meal?

This is either a GREEN IMMIGRANT LEAF WEEVIL (Polydrosus formorus https://bugguide.net/node/view/1678834/bgimage) or the slightly smaller (and equally alien) PALE GREEN WEEVIL (Polydrosus impressifrons https://bugguide.net/node/view/1813505/bgimage).  Whichever it is, it’s been in North America for a little more than a century.  Bugguide.net calls them “adventive” – introduced but not well established.  Eggs are laid in bark crevices or in the soil, and the larvae feed on roots.  Adults eat young leaves, buds, and flowers of some hardwood, fruit, and landscape trees but are not considered big pests.  Their lime-green color comes from iridescent, green scales.

And a DOT-TAILED WHITEFACE in a pear tree.

Have a Wonder-full New Year,

Kate Redmond, The BugLady

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

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/bgimage, https://bugguide.net/node/view/647825/bgimage, https://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/

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