Author: rbuchholz

Greetings, BugFans,

A funny thing happened on the way to this BOTW.  The BugLady spent the morning on-line, trying to discover the identities of a few moths.  Suddenly, a screen popped up (and a voice came from her speakers) saying that this was a Microsoft Alert!!!  That her Internet was Blocked (it sure was – frozen solid, had to turn the computer off, and the screen came back when she restarted), that her Credit Card Info was At Risk, and Also her Photos (Yikes!!!), etc., and please call an 877 number immediately.  Yeah, right.  She always tries to practice safe surfing, but her tech guru, BugFan Becca, told her that internet evildoers sometimes plant their little bombs on obscure sites because the security there may be lax compared to bigger sites.  No surprise, if you call them back, they’ll be happy to take your credit card number in exchange for fixing the problem.  The BugLady was also assured that no bad stuff will travel with this post.

So – microlepidoptera are, as you’d expect, a big group of small moths.  It’s not exactly a scientific classification; there’s no single structure or life style that definitively says micro or macro.  To some extent, it’s a grouping that’s determined by the size of the moth; there are some families that include both macro and micro species, and the families of the micros tend to be more primitive than those of the macros.  As Wikipedia says, “Plans to stabilize the term have usually proven inadequate.” The group is very diverse and includes a bunch of day-flying species, and the biographies of many have not been written.  Remember – of the 18,000 or so species of Lepidopterans in North America, more than 11,000 are moths. Here are three (and a half) of them.

SYNCOPACMA NIGRELLA (no common name) is on the BugLady’s “porch bug” list; it showed up on a fine evening in late August.  It belongs to the Twirler moth family Gelechiidae, a large family with about 4,500 species globally (650 in North America). The family contains species that are agricultural pests and species that are biological controls of agricultural pests.

Syncopacma nigrella one of about five species in its genus in North America; this species is mostly found in the eastern US, but it also occurs in California, Wyoming, and Washington.  It’s about a half-inch long, and the slim, fringed wings are typical of the family.

Gelechiid larvae often feed under cover, on the insides of their host plants – Syncopacma nigrella prefers lupines (of which the BugLady has none).

We have met Crambid moths/Grass moths/Crambid snout moths (family Crambidae) before, in the form of the orange mint moth, the white-spotted sable moth, and the eastern grass veneer moth.  Crambids have wingspreads of ½” to 1 ¼” and have tympanal organs (ears) on their abdomens and hairy mouthparts that extend forward (and that put the “snout” in “snout moth”) (the hairs are sensory and give the moth information about its surroundings).  According to bugguide.net, the larvae are stem borers, root feeders, leaf tiers, and leaf miners, and the larvae of one group is only found in the nests of arboreal ants!  Adults of some species seek nectar on flowers and probably do a little pollinating.

The BugLady gets a kick out of the subtle patterns and silvery accents that are sported by some grass veneers, and by the way they sit, wings rolled up instead of folded over their backs.  The grass veneers are said to be twig mimics.

The VAGABOND CRAMBUS (Agriphila vulgivagellus) is also called the Vagabond sod webworm, which gives us a clue to what the larvae do for a living.  The species can be seen in late summer and early fall around grasslands and gardens, from the Atlantic coast to the Great Plains and north into Canada.

Adults are found perched in the grass by day, and are crepuscular (dawn/dusk) and nocturnal flyers. They fly over the grass-tops in September, sometimes in large numbers, drinking dew from the blades, and females lay eggs (60 per day for two weeks) by dropping them into the grass as they fly.  The larvae feed on a variety of grasses and grains.  They overwinter as immature larvae that awaken in spring and feed on grasses from a webbed tube they construct on the ground.  The vagabond sod webworm has a single generation per year and is not considered as serious a pest as other species of sod webworms because the grass blades they eat in fall and in spring are growing fast.

JULIA’S DICYMOLOMIA (Dicymolomia julianalis) led the BugLady on a merry chase through moth books and websites.  She found this lovely creature (and another species to be named later) on composites in early summer.  It is also in the Crambid family and is also found over the eastern side of North America.  The moth could perch on the BugLady’s thumbnail with plenty of room to spare.

The larval menu is diverse and includes cattails, the primary host, but also Opuntia cacti, a few composites, and the egg clusters of evergreen bagworms.  Eggs are inserted into cattail heads in mid-summer, and the larvae feed on fresh and then dried flower parts and on the seeds, digging deeper into the cattail head as they get older (a little lump on an otherwise-smooth cattail shows where they are feeding). The larvae spin silk through their chambers to hold the cattail head together and keep the seeds from scattering.  Half-grown larvae overwinter in the cattail head, and they also pupate there in early summer.

And the half-moth?

The BugLady chased these beautiful rust and silver moths around the Riveredge prairie, and when she put her pictures up on the screen, she (eventually) noticed some variation in pattern that hadn’t registered out in the field (and this is why her field identification skills are going south – she can sit and stare, with a book in her hand, at insects on a screen, and they don’t fly away (except, see paragraph one)).  She realized that one species (which turned out to be Julia’s Dicymolomia) had silver “suspenders” across the top of its wings, and the other had a horizontal silver band across the wings, about a quarter of the way south of the head.  Same patch of prairie, same time of day, same time of year, same composites.

Still looking – being careful of obscure moth sites – if it’s not a Dicymolomia, it might be a Chalcoela.  If anyone else would like to play, try http://bugguide.net/node/view/39603/bgpage and http://bugguide.net/node/view/29597/bgpage.  And maybe an adult beverage.

Kate Redmond, The BugLady

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

Howdy BugFans,

Spring is coming, and home gardeners have had a gleam in their eyes ever since the first seed catalog landed in the mailbox.  Sheaves of asparagus shiver on beds of ice in grocery stores, and foragers are anxious for those first stalks of “volunteer” asparagus to peek up along the roadsides.  They’re not the only ones who are waiting.

Asparagus beetles, in the leaf beetle family (Chrysomelidae), are asparagus specialists.  They’re lovely little beetles, and two species grace our area, the asparagus/common asparagus beetle (Criocerus asparagi) and the spotted/12-spotted asparagus beetle (Crioceris duodecimpunctata) (yes – Latin for “12-dotted”).  The common is, well, more common.  We tend to talk about them generically, but there are some important distinctions.

Both beetles are aliens – Eurasian natives that arrived here in the second half of the 19^th century and now occupy anyplace in North America where asparagus is grown.  The common asparagus beetle has even made its way to Hawaii.  The two species don’t look much alike – the 12-spotted asparagus beetle can be mistaken for a ladybug at a quick glance (one source points out that they even have spots on their “kneecaps”), and the spotting on the common asparagus beetle is variable.

The “what” and the “when” of their feeding makes the common asparagus beetle the less welcome of the two.  Both chew on asparagus spears, which can cause stunting and other cosmetic damage that make the asparagus unmarketable (and consumers don’t enjoy picking up a spear with a bunch of eggs glued to it or a smear of frass (bug poop) on it, either) http://bugguide.net/node/view/16283/bgimage.

Both species overwinter as adults in hollow asparagus stems, or under leaf litter, garden debris, or loose bark – that way, when the sun warms the soil and the asparagus spears poke their heads up in spring, the beetles are already in the neighborhood.  The common asparagus beetle is the first to wake up, and it also feeds on the lacy leaves, which can defoliate and weaken the plant, a perennial (no leaves = no photosynthesis = no food storage) and can make it susceptible to fungal infections.  Its larvae also eat the spears and leaves.

After some fun in the sun, http://bugguide.net/node/view/17260/bgimage the common asparagus beetle lays its eggs in rows of 3 to 8 on the new spears, leaves or flower buds http://bugguide.net/node/view/1109490.  There’s not much of a courtship, but she may parry his moves by turning her abdomen aside or by kicking.  To protect their genetic investment, males guard females after mating, remaining piggyback during ovipositing.  Female Chrysomelids have the ability to favor the sperm of a suitor by keeping eggs fertilized by a male if they like the cut of his jib and ejecting the sperm of previous males.  The young hatch within a week and start feeding http://bugguide.net/node/view/170240.  There may be two generations of common asparagus beetles each summer here in God’s Country, and up to five generations a year where the growing season is longer.

The 12-spotted gets out of the gate a little later in spring, and it also eats the spears and leaves, but its larvae concentrate on the fruits and don’t damage the plant (not a problem unless you raise asparagus for seed, and most growers don’t – they’re in it for the vegetable and they cultivate higher-yield, (seedless) male plants).  It lays one egg at a time on the leaves; the larvae hatch, head for the fruits, and burrow inside.  There are two generations per year, and they generally finish their life cycle by mid-summer.  The larvae of both species pupate in cocoons in the soil.

What eats asparagus beetles?  Ladybugs, ground beetles, wasps, flies, predaceous stinkbugs, dragon and damselflies, damsel bugs, lacewings, and a variety of birds including farmyard fowl.  Its most efficient predator seems to be a small, blue-black wasp, Tetrastichus asparagi, that is a parasitoid of the beetle larvae and that must develop a taste for them, because as an adult, it eats the egg masses.  One study in Massachusetts showed the wasp demolishing a hefty 50% of beetle eggs in an area and then parasitizing half of the remaining eggs.  It uses its antennae and/or ovipositor to detect hosts that are already parasitized and doesn’t waste its time on them, and it targets only the common asparagus beetle (alas for the 12-spotted; a different species in the wasp’s genus goes after them).

What does an asparagus beetle do when it’s alarmed?  Common asparagus beetles have several arrows in their quivers.  They may scoot over and hide on the other side of the stalk, may do the classic Chrysomelid drop to the ground, or may resort to secretions from defensive glands.  The 12-spotted beetles escape by flight.  Both species use stridulation – making noise by rubbing two body parts together (in the case of asparagus beetles, a part of the abdominal exoskeleton rubs against teeth on the hard wing covers), both to scare predators and to communicate with other beetles.

Kate Redmond, The BugLady

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

Salutations, BugFans,

What follows is a major overhaul of a BOTW from May, 2008.  New pictures, new facts.  Remember what the naturalists at Riveredge tell the kids – “Scientists don’t say ‘EEiiiooouuuwwww!’  Scientists say “Oooohhhhh, how interesting!’”

Let us pause for a moment to salute that classic movie, “The African Queen.”  People may not recall the characters’ names or whether he stopped drinking or she started drinking or whether the boat went over Victoria Falls or even who won WWI, but they always remember the leech scene.

Continue reading “Bug o’the Week – Leeches, revisited”

Howdy, BugFans,

The star of today’s show is one of several stink bugs that the BugLady photographed during the Stink Bug Summer of 2016.  A pair of stink bugs was featured a few months ago, one a carnivore, and the other an herbivore.  The herbivore, the Twice-stabbed stink bug, includes a few agricultural crops on its menu but is not generally considered a big pest.  The star of today’s show is an herbivore that on the Most Wanted lists of Extension agencies everywhere.

Stink bugs are a long-time favorite of the BugLady.  They belong to the family Pentatomidae, which is in the Order Hemiptera, and they have the mouthparts to prove it – a sharp-tipped tubular “beak” that allows them to pierce their prey, inject a tissue-tenderizing chemical saliva, and then suck out the resulting goop.  They are solid, no-nonsense bugs whose name is well-deserved, being endowed (at the other end) with glands that manufacture chemicals which, when sprayed, make their predators think again (alas, not all are deterred).  They come in a rainbow of colors and even the nymphs are pretty.

Continue reading “Bug o’the Week – Brown Stink Bug”

Salutations, BugFans,

The BugLady never met a water lily she didn’t admire, and as she takes (inevitably-over-exposed) pictures of the flowers, she always looks to see who’s visiting the plant.  In 2013, while she was photographing the magnificent water lily planthopper (Megamelus davisi), she also found an adult, larva and pupa of some sort of Chrysomelid (leaf beetle) on the water lily leaves, and later a pupa with a cluster fly perched on it (with no evil intent – cluster flies are nectar-feeders).  That same year, the BugLady wrote an article about a beetle in the genus Donacia, also in the family Chrysomelidae, also called the Water lily leaf beetle.

Chrysomelidae is a very large, diverse family of beetles that are vegetarians both as larvae (roots, stems, leaves) and as adults (leaves, flower parts).  They often target specific plants and are named after them.  Some are agricultural pests and some are biological controls of pest species.  There are some 1,900 species of Chrysomelids in North America and 35,000 species worldwide, and there may be an equal number awaiting discovery.

So, one day, the BugLady Googled “Chrysomelid, water lily.”  Ain’t the internet grand!  The Water lily leaf beetle du jour turns out to be Galerucella nymphaeae, formerly known as Pyrrhalta nymphaeae.  It’s found throughout North America, wherever its host plants grow, and in northern Europe.  Evans, in Beetles of Eastern North America, describes its range as “Europe; widely established in North America.”

It feeds primarily on water lilies (Nuphar and Nymphaea) and smartweeds (Polygonium); each of the two distinct plant families presents unique feeding challenges, and it has been suggested that there are two, specialized races of WLLBs, with slightly different sizes, colors and jaw widths.  A study in which larvae were mixed and matched with either food plant showed that not all host plants are created equal – beetles preferred, grew faster on, and had higher survival rates on their natal plants.  Selection is reinforced by the fact that they mate and lay eggs there.

The BugLady’s first (stray) thought, when she saw the pupa on the water lily leaf, was, “Hmm – wonder how that got there.”  Her second thought was, “Well, Duh (head smack), it hatched there!”  And, her third thought was, “pretty safe spot to grow up.”  Alas, not so.  The beetles’ feeding – they chew little holes and trenches into the top surface of the leaf – hastens the decay of the leaf and makes it, like a boat with holes, less buoyant.  A leaf that’s just one- quarter eaten can become unusable, and they may literally eat their island out from under themselves.  This happens sooner rather than later if there are several larvae present, and the only escape is trekking to an adjacent leaf.

Female WLLBs lay their eggs above the water, a few per leaf, and they prefer to oviposit on younger leaves because these leaves allow optimal weight gain for their offspring.  The eggs hatch about a week later, and the clock is ticking.  Since the average leaf lasts less than a month and a larva needs more time than that to mature, emigration is a given; no matter what the population density, and the larvae start spreading to different leaves at a young age.  Grazing/defoliation causes some kinds of plants to produce more leaves, but this isn’t true of water lilies.

There are probably two generations per year, with the second overwintering as adults.

Adults are listed as “semiaquatic,” they’re found on leaves around the edges of shallow wetlands.  How do they get around?  Researcher Haripirya Mukundarajan, who studied the physics of the beetles’ movement over the water, calls it “waterskiing.”  The WLLB lifts its middle pair of legs, raises its elytra (wing covers), angles its body upwards, and uses its flying wings to scoot along the surface film at a half-meter per second (500 km/hour in human terms).  It’s reminiscent of a diving duck running across the water in order to gain lift, but the beetle has no intention of taking to the air.  The beetles, says Ms. Mukundarajan “move so fast that they interact with the ripples generated by their own motion, which increases drag and causes a bumpy ride.  It’s as if surface tension acts as a pogo stick that the beetle is jumping on.”  According to the study, the beetles’ strong wings “allow them to produce a lot of lift while counteracting drag from the surface. And their legs are covered with tiny hairs that repel water while a claw at the tip is hydrophilic [water-loving], allowing them to pin themselves to the surface of the water.  This structure is critical for the beetle to maintain its level exactly on the water surface.”  See the video at https://www.newscientist.com/article/2079427-the-secret-of-beetles-that-waterski-so-fast-they-vanish/.  Practical applications?  According to the article, “understanding the motion of the beetles could help us develop robots that move across water quickly. Many current designs are based on water striders, which move more slowly.”

The WLLB comes from a distinguished lineage.  According to bugguide.net, the “beetles have been raised in the lab on Purple Loosestrife (Lythrum salicaria),” and two European Galerucella (“Cella”) beetles, Galerucella pusilla and Galerucella calmariensis, are presently being raised for release on purple loose strife on these shores.

And then there’s water chestnut, an invasive aquatic plant in Northeastern North America whose seed pod you do not want to encounter while barefoot https://nas.er.usgs.gov/queries/greatlakes/FactSheet.aspx?SpeciesID=263&Potential=N&Type=0.  The WLLB has been suggested as a control for Water chestnut.  In a study to determine whether Galerucella birmanica, a related beetle from Asia, should be introduced to control water chestnut, the native beetle acted as a testing surrogate.  Turned out that Galerucella nymphaeae larvae were eaten with gusto by backswimmers and by a ladybug called the spotted or the pink spotted (but not the pink–spotted) lady beetle, preventing larval populations from rising to the levels needed for biocontrol.  It didn’t help that while larval Galerucella nymphaeae will feed naturally on water chestnut, their survival rate there is very low.  Water chestnut leaves are small and get eaten faster, which results in more frequent leaf-switching, which results in more larval drownings.  Also, adults reared as larvae on the exotic water chestnut reverted to native plants when given a chance.  Back to the drawing board (but, the BugLady is heartened that these experiments were carried out, rather than simply importing the Asian species and throwing it out into the field to see what would happen, like we did in the bad old days).

A European study painted a picture of coots, swimming among the water lily leaves, picking the beetles/pupae/larvae off of the leaves.

Kate Redmond, The BugLady
Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Salutations, BugFans,

Caddisflies are famous for having soft-bodied, aquatic larvae that, depending on their species and habitat, use plant materials or teeny stones to construct portable cases that may be “log-cabin,” tube, or snail shell-shaped http://bugguide.net/node/view/258710/bgpage (caddisflies that live in strong currents may spin nets instead).  For “glue,” they use silk that they produce in a gland in their “lower lip.”  Some people “farm” caddisfly larvae, giving them bits of semiprecious stones and metals to build with and then making jewelry from the shed cases (you can Google it).

In the early days of modern taxonomy, caddisflies (now order Trichoptera) were listed with dragonflies, stoneflies, mayflies, dobsonflies (hellgrammites), lacewings, and more, in the order Neuroptera, but caddisflies were split off 200 years ago.  Their larvae look caterpillar-ish and the adults are often mistaken for moths, so it’s not surprising that caddisflies are closely related to the Lepidopterans.

Continue reading “Bug o’the Week – Giant Casemaker Caddisfly”

Greetings, BugFans,

No – not March yet, but it will be some day.  Actually, the BugLady had to wait until the end of October to find this March fly (Bibio slossonae) (probably).  She was walking in her favorite wetland on a cool, fall day and assumed that the flies around her were midges (famous for their cold-weather flights) until, as she photographed a grouse locust, along came a March fly, and sat down beside her.

Continue reading “Bug o’the Week – March Fly”

Howdy, BugFans,

About six years ago, the BugLady posted three episodes about galls.  What are galls?  Technically speaking, a gall is an abnormal growth or swelling of external tissues.  In animals, “gall” may refer to a sore or callus caused by chafing, and the same definition applies to the thickened “scar tissue” that occurs where two tree limbs rub against each other.  “Gall” (alternately, “canker”) also refers to a plant tissue growth triggered by bacteria or fungi.  The “bug-centric” among us, however, think of galls in narrower terms – they are the variously-shaped growths instigated by arthropods on plant tissue (the name “gall” refers to the bitter taste of some tannin-rich galls).

Continue reading “Bug o’the Week – Galls IV – Two Oaks and a Hickory”

Greetings, BugFans,

From the start, the main criterion for any BOTW episode has been a reasonably good picture of its protagonist (second is whether the BugLady can discover its story).  Alas – it’s January, and it’s 439 episodes later, and the bar is getting lower.  Meet the Golden/Yellow dung fly.

Its geographic range includes cooler, temperate regions throughout much of the world, and it probably arrived in North America from Europe early-on, with shipments of cattle.  It is associated with agricultural areas but is found wherever there is dung from large-ish mammals for its eggs and larvae.  Although references list golden dung flies as fairly common (especially if you hang around farmyards), the BugLady has only photographed them a few times over the past eight years, and never well.

Continue reading “Bug o’the Week – Golden Dung Fly”

Howdy, BugFans,

The BugLady’s #3 child nailed it years ago when she proclaimed her mother an “Essoterrorist” – someone with a fondness for squirreling away obscure facts.  Here are some of the Bug Facts that she’s come across while looking for something else.

Zika among us 

As overzealous communities in the path of the Zika virus consider “nuking the wetlands,” remember that Zika-carrying mosquitoes don’t rough it out in the wild, they are suburban-urban-dwellers.  “There are over 3,000 mosquito species worldwide, but only a couple of hundred are important medically,” says Janet McAllister, Ph.D. of the CDC. “That’s because most species of mosquito don’t even bite humans — some prefer other animals like amphibians and reptiles.”  See five common mosquito myths at http://www.huffingtonpost.com/2013/05/26/mosquito-myths-misconceptions-insects-diseases_n_3328497.html.  The average mosquito consumes 1/1,000,000 gallon per bite (it would take 1,129,000 bites to drain the blood from the average human) http://www.caprince.com/turtle/Documents/mos3.pdf.

Insects in the Art Gallery

Albrecht Durer, a 15^th/16^th century German artist whom the BugLady admires, produced an engraving at the end of the 15^th century that is variously called The Holy Family with the Dragonfly, The Holy Family with the Mayfly, The Holy Family with the Locust, and The Holy Family with the Butterfly.  Wikipedia tells us that “In the lower right corner is an insect frequently identified as a dragonfly. However, Dürer may have intended it as a butterfly, a creature whose dramatically transformative life-cycle makes it a perfect symbol of resurrection and redemption.” Click to magnify the picture and make a guess: https://upload.wikimedia.org/wikipedia/commons/8/89/The_Holy_Family_with_the_Dragonfly_by_Albrecht_Durer.jpg.

One-liner

Another gem from Wikipedia: “Arthropods are so versatile that they have been compared to Swiss Army knives.”

How many???

From the Smithsonian:

• Insects probably have the largest biomass of the terrestrial animals. At any time, it is estimated that there are some 10 quintillion (10,000,000,000,000,000,000) individual insects alive.
• In the world, some 900,000 different kinds of living insects are known. 91,000 species have been described in the US, but there may be 73,000 more species waiting to be discovered/described here.
• Someone did the math on soil samples taken to a depth of 5” in plots in North Carolina and projected that the soil contained 124 million animals per acre.  Mites and springtails ruled, with 90 million and 28 million each.  4 ½ million were “other insects.”  A similar study in Pennsylvania suggested 425 million animals per acre.
• Assuming no mortality of their offspring or their offspring’s’ offspring’s offspring, a single pair of house flies might be patriarch and matriarch to 190 quintillion young in five months.
• There are 200,000,000 individual insects for every man, woman and child on the planet. See http://www.si.edu/Encyclopedia_SI/nmnh/buginfo/bugnos.htm for more.

But – who’s counting?

In an article in Science 2 magazine in 2010, author Robert M. May considers how to answer an extraterrestrial’s obvious question “How many distinct life forms—species—does your planet have?” But, he notes, look who’s doing the counting.  He tells us that “we began systematically naming species just a little over two centuries ago, and that our labor force is inefficiently distributed: about one-third of taxonomists work on vertebrates (at most 1% of the total number of species), one-third on plants (around 10%), and the remaining one-third on invertebrates (comprising at least 90%). Furthermore, a lack of broad, synoptic databases and problems with synonyms—the same species cataloged differently in different collections—means that we are uncertain, by around 10%, of how many distinct species we actually have named and recorded.”  So, what’s the grand total?  Read all about it at https://www.researchgate.net/publication/44902098_Tropical_Arthropod_Species_More_or_Less.

A spoiler alert from May: “Overall, these conclusions imply that around two-thirds of all arthropod species still await discovery and description. In part, this sorry state of affairs reflects inefficient distribution of taxonomic attention, which is disproportionately directed to the more appealing furry and feathery vertebrates. It also often reflects a tendency for funding agencies, in the United Kingdom and elsewhere, to view research on basic systematics and taxonomy as insufficiently sexy …..  My guess is that the hypothetical aliens would take a dim view of all this.”

Plutarch may have gotten this wrong 

About dung beetles, sacred to the Egyptians, Plutarch wrote: “The race of beetles has no female, but all the males eject their sperm into a round pellet of material which they roll up by pushing it from the opposite side, just as the sun seems to turn the heavens in the direction opposite to its own course, which is from west to east.”

Not just another pretty face

The BugLady crowds her front porch with geraniums each summer and brings them all inside (usually at midnight, with a heavy freeze descending) and then abuses them all winter by forgetting to water them (her picture is probably posted near the cash register at area garden stores – Do Not Sell to.…).  Now she appreciates them even more.  Turns out that chemicals in the petals (maybe the leaves, too) paralyze herbivores like Japanese beetles for a few hours, during which time they are more vulnerable to predators http://blog.extension.uconn.edu/2015/03/02/plant-defenses-against-insects/.

Survey Says 

Researchers drove two road routes (one forested, one urban) through the Northeastern part of the continent to test an old insect censusing method made new – they substituted sticky tape on the front bumper for the time-honored radiator grill.  In analyzing the 400,000 bits of DNA found adhering to the tape, they identified up to 2,000 insect species and many (many) species of bacteria, as well as other microbes, plant bits, and non-insect animals (including human).  It’s called metagenomics – the study of DNA recovered from environmental samples, and needless to say, the database/technology for this kind of sampling is being built on the go.  For a very scientific explanation: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775585/; for a slightly less scientific explanation: https://mentalindigestion.net/2009/11/20/windshield-splatter-analysis/.

Who Knew??

Scientists Worthen and Hart, who were studying the ability of some dragon/damselflies to reject parasitic mites more effectively than others, made these observations (Hydraphantidae Limnocaridae, and Arrenuridae are mite families): Hydraphantids and limnocarids have terrestrial larvae that either leap from the surface of the water to infect mature odonates in flight or colonize odonates perching along the shoreline [emphasis, the BugLady, who has no visual of a mite leaping]. Arrenurids have aquatic larvae; most species colonize odonate naiads and begin to feed on the emerging adult at ecdysis, but some species colonize mature odonates returning to water to mate or oviposithttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC4864583/.  Mites like crane flies like the one pictured here, too, many of whose larvae are aquatic.

New Age hornets

Oriental hornets (Vespa orientalis) generally build their communal nests underground, excavating bits of soil and building cells for eggs and larvae, (they may opt for an above-ground, paper nest).  Either way, it’s dark inside – how’s a gal supposed to tell which way’s up?

It turns out that they orient using gravity, but they also embed (using saliva) a tiny “keystone” crystal in the “ceiling” of each cell. “The resulting network of crystals, researchers say, may serve the same purpose as a surveyor’s level, helping the insects maintain symmetry and balance when building their precisely oriented and uniform nests” https://www.scientificamerican.com/article/keystone-like-crystals-ma/.

Vibrations in the nest cause the crystals to vibrate and allow the hornets to gather information.  Says John Pickrell in “Mystery in a Hornet’s Nest,” “When the hornets tap the hive surface with their feet, the crystal does not dance in the same way as the rest of the comb, enabling the insects to glean information about the orientation of their nest.”

The tiny, magnetic crystals contain titanium, oxygen, iron, and carbon – all elements that are readily available in the hornet’s environment – and in their bodies; there is speculation that rather than hunting for them, the hornets manufacture the crystals themselves!  Oriental hornets are multitalented; http://news.nationalgeographic.com/news/2010/12/101221-solar-power-hornet-science-animals/.

And that’s how it is – always.

“Each observation, however, has raised more questions than it answers, so the sum of my watching has caused me to grow in ignorance, not in knowledge.”  Sue Hubbell, chapter on Camel crickets in Broadsides from the Other Orders. 

The BugLady