Bug o’ the Week – Phantom Crane Fly

Salutations, BugFans,

 

What an excellent fly!

 

Most BugFans are familiar with crane flies (those giant, non-biting “mosquitoes” in the family Tipulidae) (keep an eye out – some of the fall-flying Tipulids are pretty spectacular).  Phantom crane flies belong in the small family Ptychopteridae (only three genera).  Crane flies of both families were named for their long legs, and most authors attribute the “phantom” part of the name to the way PCFs drift through the air, appearing and disappearing in patches of light and shadow.  Our PCF (Bittacomorpha clavipes) can be seen east of the Rockies, from late spring to early autumn, in the fairly dense vegetation along the shady edges of wetlands.

 

They aren’t huge.  If you join the tips of your thumb and forefinger, you’d be approximating the leg-span.  They’re like a flying daddy long-legs, but without the bulk – a PCF body is a slender half-inch.  Sources describe them as floating through the air, legs spread, flapping their wings minimally, assisted aerodynamically by the flared areas on their legs.  Can they fly up-wind?  Yes, if the breeze isn’t too strong, but most of the time, they appear to move randomly through the vegetation, two or three feet off the ground, ricocheting off of leaves.

 

The odd flanges on the legs are a characteristic of this species.  Twentieth century entomologist C. P. Alexander (who described more than 11,000 species and genera of flies during his long career) said of the PCF that “This species is one of the most conspicuous and interesting of all Nearctic Diptera. The first tarsomere of the legs is dilated and filled with tracheae, a characteristic which enables the flies to drift in the wind with their long legs extended to catch the breeze.

 

Let’s “unpack” the trachea-tarsomere thing.  The tarsus is the lower part of an insect’s leg – its “foot” – located below the tibia.  It’s made up of a series of small segments (usually five) called tarsomeres; the top segment is called the metatarsus, and the bottom segment usually bears a claw or two.  The insect walks or hops on its tarsus.

 

Insects breathe largely by diffusion; their respiration is mostly passive (although muscle contractions can push air through the respiratory system more quickly).  Air floats through openings called spiracles into tubes called trachea.  It moves through a network of increasingly minute respiratory tubing that divides and subdivides and ends in moist pockets called tracheoles where the cells can exchange waste gases for fresh.  Trachea may be strengthened by spiral fibers called taenidia that are embedded in their walls; taenidia have been likened to the coils in a dryer vent tube.  In the absence of taenidia, a tracheal wall may bulge out like an aneurism and form an air sac.

 

Still unpacking.  In his article called “Peculiar Tracheal Dilations in Bittacomorpha clavipes,” published in the Biological Bulletin in 1900, Charles Thomas Brues explains further.  “In both sexes, the metatarsi are very much enlarged and quite conspicuous on account of their great color contrast. The whole tibia is completely filled up by the tracheaIn the enlarged metatarsus, the trachea is enormously distended and almost completely fills the cavity of this joint as well as that of the second and third joints of the tarsus.”  In Tipulidae, the tracheal tube is delicate-to-obsolete in the tarsus.  “it is impossible that they [av_immense vesicles in the metatarsi] should be used as reservoirs for air for respiration, on account of their distance from the body of the insect.  It is more probable that they may bear some relation to the insect’s method of locomotion.  When flying, Bittacomorpha uses the wings scarcely at all, relying in great measure upon wind currents for transportation.  The legs are exceedingly light, as the exoskeleton is light and delicate, and encloses practically no tissue that can serve to increase their weight.  As they expose a large surface, they offer great resistance to the air without adding appreciably to the insect’s weight.

 

So, the hollow legs lighten the insect, and the inflated sacs increase buoyancy and provide surface area for the wind to push on.

 

How do PCFs get away with their striking, black and white patterns?  Aposematic/warning coloration has been suggested, but the folks who keep track of these things tell us that the rest of the crane flies taste OK, and there’s no reason to suspect that PCFs taste otherwise (the aquatic larvae scavenge on organic detritus in the water that surrounds them, and the adults eat little or nothing – they’re not blood suckers!.  Nothing suspicious there).  As previously noted, black and white coloration is a good plan for an animal that inhabits the light-speckled thickets, and the BugLady assumes that they’re as tough for predators to see as they are for photographers.  A blogger in Michigan suggests that Crane fly legs are oh-so-easily detachable, and that the PCF may sacrifice a conspicuously-striped leg to save its life.

 

Clearly, PCFs have caught our fancy, and it’s fun to note the words that are used to describe them and their flight:

  • They resemble a spider web or a thistle seed drifting about.”
  • It looks a bit like a flying snowflake.”
  • It hangs or floats in the air rather than flies, spreading its long legs to catch the breeze, a little like ballooning in spiders.”
  • They appear like parachutes floating above streamside grasses and sedges.”
  •  “When the legs are vibrate, this insect indeed lives up to its name, giving the beholders a sensation of “spots before the eyes.”
  • The same Michigan blogger notes, interestingly, that “When it flies, it looks like a tight swarm of up to seven small flies, rather than a single large one.”

If the BugLady were to pick an adjective, it would be “flickering,” and she thinks they look like tiny sparklers.

 

The BugLady was lucky enough to witness a few happy PCF couples flying around in tandem.  Both in flight and when hanging from a leaf, the female provides the muscle.  Twice, as the BugLady was (voyeuristically) photographing a mating pair, a third PCF flew in and hassled the female.

 

Subsequently, the female dips the tip of her abdomen into the water, depositing eggs (as many as 300 of them) singly or in small bunches.  The larvae live in the top inch or so of muck and feed on decaying material they find there.  It’s not exactly an oxygen-rich environment, and although they can pick up gases through their soft exoskeleton, they get the bulk of their air through a long, retractable breathing tube (caudal respiratory siphon) that they extend up through the surface film from the rear of their body.  According to Voshell in A Guide to Common Freshwater Invertebrates of North America, the larvae “burrow deep into sediment during periods of the winter when the water freezes over.  Pupation occurs in the same habitat where the larvae develop, without any special preparation.  Pupae have long, breathing tube on the thorax.”  There are reportedly two broods in the northern part of its range.

 

PCFs have been putting on small but exquisite performances since Eocene times, and they’re now showing at a wetland near you!

 

On another note – the BugLady has been enjoying the sweet serenades of the tree crickets recently.  Here are links to two audio sites from last year’s BOTW on tree crickets:  Go to http://www.oecanthinae.com/4099.html, turn up the volume on your speakers, and scroll down slowly.  And, try the U of Florida’s recordings of crickets and katydids north of Mexico at http://entomology.ifas.ufl.edu/walker/buzz/cricklist.htm.  Fair warning – you have to listen pretty hard to hear some tree crickets.

 

The BugLady

Bug o’ the Week – Wooly Alder Aphid

Salutations, BugFans,

 

We have already met the Wooly Alder Aphid (Prociphilus tessellatus) (tessellateto form or arrange in a checkered or mosaic pattern), through the eyes of one of its predators, the carnivorous caterpillar of the Harvester butterfly, but it has its own story to tell.  Wooly Alder Aphids (wooly or woolly – both spellings are correct) are not the only wooly

aphids, but they are a common species that can be particularly noticeable in autumn, as leaves fall (the BugLady has also included a picture of some wooly “beech blight aphids” that she found last fall.  They were doing the most astonishing alarm behavior, a behavior that has earned them the name “Boogie Woogie aphid.”  Watch the video at http://en.wikipedia.org/wiki/Beech_blight_aphid).

 

Wooly aphids (family Aphididae, subfamily Eriosomatinae) are spectacular when sitting on twigs in large assemblages, and startling as individuals, flying through the air like bits of fluff or feathers.  Their aerial appearance has earned them common names like fairy flies, fluff bugs, and angel bugs.  They’ve also been given the slightly less flattering name “maple blight aphids.”

 

The “wool” on a wooly aphid is wax, produced by abdominal glands in order to make the aphid look less like a Happy Meal to its predators.  The wax streamers shed water, make the aphid look like mold, and are distasteful and distracting (the Harvester caterpillar covers itself in aphid wax, too, and so does the marauding green lacewing larva).  Several sources suggested that the strands also assist a wooly aphid when it’s aloft, helping it float in the breezes and disguising it as an airborne plant seed.  Some, but not all adults are wooly.

 

Like many other WAs, a WAA’s lifestyle is complicated, involving two host plants at two different stages of its life.  For much of her life, a female aphid reproduces parthenogenetically, popping out live young (clones) all over her host plant without benefit of male companionship and without eggs (no-frills reproduction).  Her young can reproduce at an early age, and it’s jokingly said that a female aphid who starts at the bottom of a plant stem is a great-great-grandmother by the time she reaches the top.  Someone once calculated that in optimal conditions – good food, balmy days, and no predators – an aphid could have six billion offspring by the end of the season!  In times of stress – when they’ve sucked a plant dry, or frosty weather is approaching – a winged generation of both males and females is produced and bodily fluids are exchanged (and genetic diversity is boosted).

 

WAAs lay their eggs on Silver maple trees (Acer saccharinum) (the eggs have woolly coats, too).  The eggs, all female, hatch in spring as leaves are bursting, and the aphids feed along the midrib of the maple leaves.  In early summer, as maple leaves are toughening up, a winged generation flies from maple trees to alder shrubs (Alnus sp.).  There, they tuck in again, imbibing alder juices.

 

Decreasing day length signals the alder crowd to produce winged generation (alternatively, they may start producing both males and females when they arrive on the alders, but these reproductive aphids don’t mature until signaled by the end of the growing season), and they make for the maples again.  Eggs are laid (just one per female!) in crevices in the bark.  Most sources state that the WWA overwinters in the egg stage, but they also mention adults overwintering on maples in fuzzy clumps.  WAAs are found in North America east of the Mississippi, and maybe adults of southern populations can overwinter successfully.

 

Aphids are plant-juice-suckers.  They stick their mouthparts in the plant of their choice and drink far more sap than a critter that size would seem to need (it comes out under pressure, too).  Why?  They’re after the sugars (the carbs) in the sap, but they also need nitrogen, which is present in very small quantities.  Young insects, especially, need nitrogen to build proteins – protein is made up of amino acids, and nitrogen is an ingredient of amino acids.  The strategy – drink LOTS AND LOTS of plant juices in order to pick up sufficient nitrogen, and jettison the unwanted carbs in the form of a sweet substance called honeydew.

 

Honeydew is a desirable commodity in the world of invertebrates.  If left alone, aphids simply drop their honeydew on surrounding leaves, where it acts like a shiny magnet for flies, wasps, bees, and other vegetarians.  But aphids, and other Homopterans like treehoppers and scales, are often seen in the company of ants.  These ant guardians care for their flocks, defend them from predators, and even transport them to greener pastures.  The payoff is that the ants may “milk” the aphids, harvesting the honeydew directly from the source and transporting it to their nests (some ant species have specialized “tanker ants”).  Research has shown that a “farmed” aphid produces more honeydew during its life than an “unfarmed” one, and according to entomologist Debbie Hadley “Some aphid species have lost the ability to poop on their own, and now depend on their caretaker ants to milk them.”  The Minnesota DNR cautions us that “while the honeydew excreted by the aphids is very sweet, it is mixed with aphid waste materials, so licking the honeydew off your car windshield is not recommended.

 

For all the plant juices that are consumed by WAAs, individually and communally, most sources agree that damage is minimal and WAA control is unnecessary (a big crowd of WAAs might cause some maple leaves to shrivel, but some other species of WAs have a much greater impact on their hosts).  As Iowa State University notes in one of its “Iowa Insect Information Notes,” “Woolly aphids are an important resource for natural biological controls such as lacewings, lady beetles, hover flies, and parasitic wasps.  Tolerance of aphid presence is one way to encourage beneficial insects.”  They go on to say “Flying adults are a wonderment.  They are intriguing, not harmful.  When adults are migrating, the feeding and honeydew production on the maples has been accomplished and no control is needed.  Relax and enjoy the fascination of Nature.”

 

That being said, there are several “down-sides” to having WAAs, and honeydew is at the top of the list.  It’s sticky, and objects that it falls on (like sidewalks, lawn furniture and cars) get sticky, too.  The wasps and bees that are attracted to honeydew have stingers.  Thick deposits of honeydew turn out to be the perfect culture medium to grow a “sooty mold,” a creepy looking crusty fungus that can cut off sunlight to a leaf surface.

 

To read about the Harvester caterpillar, check http://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/harvesterbutterfly.cfm.

 

World Wide Web note:  The BugLady can never resist, when she’s doing a search for something like Prociphilus tessellatus, clicking on the inevitable “Lyrics containing the term Prociphilus tessellatus” site.  Surprisingly, there weren’t any.

 

The BugLady

Bug o’ the Week – Checkered Beetle

Salutations, BugFans,

 

The BugLady chased this speedy little Checkered beetle (probably Enoclerus rosmarus) around a wild sunflower stalk for a while, and these are the best pictures she could get.  When she first saw it out of the corner of her eye, she thought that it was a particularly colorful ant, and that’s the point.  There’s a group of wasps called “Velvet Ants” whose females are wingless (and furry) http://bugguide.net/node/view/956650/bgimage.  They occur in dry, sandy areas from the Southwest and southern Great Plains, through the Gulf States and up the Atlantic coast as far as Connecticut (the BugLady has seen them in Texas and southern New Jersey).  The fact that they are also called “Cow-killer ants” hints at how their sting feels.  This genus of checkered beetles has picked a good group to mimic, because nobody messes with Velvet Ants.

 

About 300 species of checkered beetles (family Cleridae) live in a variety of habitats in North America (there are about 3,500 species worldwide).  As a group they are small-ish, hairy, long and narrow, and brightly-patterned.  Their head is wide, their thorax tapers, and the elytra (hard wing covers) are broader than the thorax.

 

CBs can be seen on flowers and in trees.  Most species are meat eaters as both larvae and adults.  Adult Clerids practice their carnivorous lifestyles in a variety of ways – the majority hunt on and under the bark of trees; some sit on flowers or sap flows and prey on visiting insects (they occasionally stop and sip the nectar and pollen themselves; adults of some species eat it exclusively and are considered noteworthy pollinators).  Still others consume insect eggs.  There are a few scavengers in the bunch, too, and some that “prey on” processed foods or on pests of processed foods.

 

Some of the under-the-bark species are considered important biological controls of the bark and wood-boring beetles whose galleries (tunnels) devalue cut timber.  If, like bark beetles, you live under bark, in the dark, you can’t use visual signals to find a mate.  You can use chemical signals called aggregation pheromones to gather a like-minded crowd, and the clever CB can tune into these pheromones to locate its meals.  Clever foresters can buy synthetic bark beetle pheromones and deploy them to attract more Clerids.

 

In general, adult CBs eat adult beetles, and their larvae feed on beetle larvae.  Ralph Swain, in The Insect Guide, calls CB larvae “the ferrets of the insect world, preying upon the larvae of bark beetles and other wood-boring beetles, moths, wasps and bees” (they can be a problem in honeybee hives), and even on gall insects.  They are able to excavate their own tunnels but are more likely to follow their prey down its tunnel.  The larvae of vegetarian CBs tend to be scavengers.

 

Females lay their eggs, a few dozen at a time, usually under the bark of a dead/dying tree that contains their larva’s prey, or in the soil.  The larvae are described as vigorous feeders – indeed, egg-laying requires so much energy that females often eat vigorously even as they’re mating.  CBs tend to overwinter in the larval stage, pupating in spring in cells they prepare in the soil or in their prey’s tunnel and emerging in summer.

 

Enoclerus rosmarus (no common name) is just under a half-inch long, covered with bristly hairs that are more dense aft than fore.  It lives in the eastern half of the US and its range extends south into Central America.  Unlike its tree-loving relatives, Er loves flowers and is found on a variety of prairie plants (one study linked them with horseweeds in the genus Conyza) and sumac, and its favorite food is nectar.  Er larvae overwinter burrowed into the stems of prairie plants, especially those in the Aster family.

 

As alert BugFans have probably noticed from the BugLady’s verbal tap-dancing, there was a dearth of specific life history information about this lovely species, but its name did come up in tantalizing references from a variety of research projects:

  • In a study by Senchina and Summerville to enumerate the insects that are associated with poison ivy.  Apparently, poison ivy is an under-studied plant (go figure!) but the Er was one species of the 37 “floral associates” noted during the study.  Poison ivy’s multitude of pollinators help it to spread.
  • Ers apparently overwinter as “inquilines” (Latin for “boarders”) in a rose stem gall (scientists bring a gall inside in the winter, put it in a screened container, and record who eventually emerges – besides the gall-maker itself.  In one study involving Willow pine cone galls, 23 galls were collected, and 564 insects were reared from them – but only 15 of the galls contained the original host gnat) (some inquilines live not-so-peaceably with their hosts).  Ers were also reared from several oak galls; a few CBs feed on gall-makers, but it wasn’t clear if the Er’s were dining, or just using the guest room.
  • In a publication called “Fauna Overwintering in or on the Stems of Wisconsin Prairie Forbs” (wildflowers), Williams reports that Ers and a surprising number of other arthropods – adults and immatures, from several rungs on the food chain – overwinter on or within the stems of Joe-Pye weed, Blazing star, etc.  This becomes important as prairie management techniques are selected – fire, mowing and grazing are hard on these highly specialized prairie invertebrates.  As Riveredge’s Andy Larsen used to say, you can try to establish a prairie, but until the sustainable partnerships of native plants and-insects are in place, all you have is prairie plantings.

 

The BugLady

What’s Blooming This Week?

New England Aster (Symphyotrichum novae-angliae)

New England Aster (photo by M.Zopp)

New England Aster (photo by M.Zopp)

New England aster is native to almost every area in North America east of the Rocky Mountains, but excluding the some of the southern United States. The plant grows up to 120 cm (47 inches) with a stout, hairy stem and lance-shaped leaves with entire margins. The flower heads are showy with yellow centers and flower petals that range from a deep purple or rose to rarely white. This species inhabits a wide variety of habitats and soil types, preferring full or partial sun over shade, and moist to average conditions. This plant can become stressed out by hot dry weather, often dropping its lower leaves in response, while the remaining leaves may turn yellow or brown

 

Indian Pipe(Monotropa uniflora)

Indian Pipe (photo by M.Zopp)

Indian Pipe (photo by M.Zopp)

 Indian pipe, also known as Corpse Plant or Ghost Plant, is one of the easiest plants to recognize. Unlike most plants, Indian Pipe doesn’t

have chlorophyll, the stuff that makes plants green. Indian pipe is waxy, whitish color turning black as it ages and only grows 4-10 inches tall.  This plant can typically be found from June to September growing in shady woods in areas near dead tree stumps and decaying plant matter. Due to the lack of chlorophyll, this plant parasitizes fungus growing on decaying material (or trees) to acquire its energy.

 

Beechdrops (Epifagus americana)

Beech Drops (photo by M.Zopp)

Beechdrops (photo by M.Zopp)

Beechdrops are parasitic plants on beech trees. Due to the lack of chlorophyll in this plant, it finds it’s nutrients not from photosynthesis but from the roots of beech trees. The plant grows 6-20 inches and produces very small reddish brown flowers.  Bloom time for beech drops is from August to October. Beechdrops look like the dying stems of some small forest herb and are easily overlooked – especially since they only appear aboveground to flower for a few weeks in the fall.

 

Indian Grass (Sorghastrum nutans)

Indian Grass (photo by M.Zopp)

Indian Grass            (photo by M.Zopp)

Indian grass is one of the beautiful, and often dominant, autumn grasses often seen prairie ecosystems.   This native perennial grass grows 3-7 ft. tall and displays a reddish-golden brown color.  The blooming period occurs during late summer to early fall.  Several species of grasshoppers feed on the foliage of Indian grass; these grasshoppers are an important source of food to many songbirds and upland game birds.

Bug o’ the Week – Snipe Fly

Howdy, BugFans,

 

Flies (which we tend to view as mangled objects at the business end of a flyswatter) belong to the large order, Diptera (“two wings”) – 100,000-plus species have been described and probably another 100,000-plus species are waiting in line for scientific attention (one out of every ten animals is a fly) (and one in every five living things is a beetle).  Members of the order are remarkably diverse (and isn’t the Class Insecta a grand study in variations on the theme of three body parts, six legs, and maybe some wings!).  Flies come in all colors, with a variety of body shapes and leg lengths, and some have astonishing eyes, but the word “beautiful” is seldom applied to them.  Except in early summer when the Gold/golden-backed snipe flies are in flight.

 

It is thought that snipe flies (family Rhagionidae) got their name from some imaginative entomologist who believed that the rather prominent proboscis that adorns some species looked like the bill of an avian snipe (and for BugFans who once endured some hazing in the classic form of a “snipe hunt,” there are, indeed, avian snipes).  SFs tend to be found on vegetation in damp, shady places, where they often perch head down; they’re slow flyers that happily dart off on foot when alarmed.

 

Adult SFs are long-legged with a round head and a tapering abdomen, and many are patterned.  They have piercing mouthparts that they may use to prey on other insects (mainly smaller flies) or to grab a blood meal from a variety of vertebrates.  Members of one SF genus (Symphoromyia) are merciless pests of bison in summer, when the bison are vulnerable because they’ve shed their thick coats.  In the West and in parts of the eastern US, females of some species bite humans.  The BugLady inhabits snipe fly habitats regularly and has never seen one on her skin.

 

The larvae (maggots) of some species of SFs are aquatic, but most others can be found in moist soil or moss or decaying logs.  They are carnivores, and in aid of that, the larvae of some western SFs do an “ant-lion” thing (and so are called “worm-lions”) – digging cone-shaped pits in slippery sand/dust and then lurking at the bottom, waiting for insects to drop in for supper.  In the “Man bites Dog” category, snipe fly egg masses were, according to one source, collected, cooked and eaten by some Native Americans.  

 

GOLD(EN)-BACKED SNIPE FLIES (Chrysopilus thoracicus) (Chrysopilus means “golden hair” and thoracicus refers to the thorax) ply the tall grasses, sedges and thickets around wetlands east of the Great Plains.  Look down – the BugLady rarely sees them higher than two feet off the ground.  With their striking gold thorax, white chevrons on the abdomen, and smoky, patterned wings, these half-inch flies are an eyeful.  Speaking of eyes, a male SF’s are much larger than the female’s.  There are 30-some members of the genus in North America, and the GBSF is the most dramatically colored.  Some sources consider them to be wasp-mimics, but the BugLady doesn’t see it.

 

GBSFs are predators on aphids and other small insects.  Their eggs are laid in bunches in leaf litter and at the soil surface, and their larvae feed on small invertebrates that they find in moss or decaying wood.

 

Since the GBSF has always been the BugLady’s mental image of “Snipe fly,” it took her a while to realize that the brownish fly with spotted wings was also a snipe fly, the COMMON SNIPE FLY (Rhagio mystaceus) (probably).  Because of their habit of surveying the world while perched head-down. a number of Rhagio snipe flies are called “down-looker flies.”

 

For a fly whose “first name” is “Common,” there’s not a lot of information out there about the CSF.  There are 25 species in the genus in North America.  CSFs seem to follow the general SF game plan; their predatory larvae feed on small invertebrates in moist soil.  Internet hits do include species lists from the United Kingdom.

 

The BugLady

Bug o’ the Week – Glowworm Beetle

Howdy, BugFans,

 

Mike and Jessica were chasing a glow-in-the-dark Frisbee around the lawn one recent night (they live well beyond the streetlights), when they realized that they weren’t alone.  There were small, luminous spots in the grass that, when they looked closer, turned out to be grub-like insects (good spotting, folks!).  They carefully picked some up, made a terrarium for them, and sent some pictures to the UWM Field Station, accompanied by a gracious invitation to see the “worms” in person.  The BugLady visited; she, Mike, Jessica, bug enthusiast Marie, and another friend admired the beetles; and the BugLady’s camera celebrated the occasion by going into a brief funk.

 

Mike said that he has seen these GLOWWORM BEETLES (most likely Phengodes plumosa, unless they’re Phengodes fusciceps) off and on over the past 20 years or so, but there’s an unusually large crop of them this year.  Many of the grubs have been found under two huge maple trees.  The BugLady hasn’t found anything in her reading to suggest that there’s a specific connection to maples or to the microclimate produced by the dense shade under the trees.  The GwBs’ typical habitat is listed as marshes, lawns and fields, damp soil with some leaf litter, and dirt beneath decaying logs.  They are nocturnal – why produce light if the sun is out?

 

Glowworm Beetles are in the glowworm beetle family Phengodidae, a New World family of about 250 species with representatives living from the southern edge of Canada all the way to Chile.  Most species live south of the Rio Grande.  Other common names include “glow-worms” (a name shared with larval Lightning beetles) and “railroad worms.”  Many species have not been thoroughly studied, Marie, and they are tricky to raise in captivity.  And, their biology and natural history embody lots of good, rich science words.

 

In the “Never-throw-anything-away” category, when the BugLady was looking at some pictures of Phengodid larvae on-line, she realized that she had photographed one in Dallas, in 1976, and that she still has the color slide (as a wise man once said, “You are what you can’t throw away.”).  It looked like this,  http://bugguide.net/node/view/583681/bgimage, but this series of pictures is much better than the BugLady’s.

 

Adult males are smallish, “bug-eyed,” glow-in-the-dark beetles with very short wing covers (elytra) and phenomenal, bipectinate antennae (their fringes have fringes).  http://bugguide.net/node/view/167293/bgimage.  Males sometimes come to lights at night, so the BugLady is checking her porch lights extra carefully.  The larvae look like fairly typical beetle grubs, and the females look like the larvae (a condition known as “larviform,” “neotonous,” or “paedomorphic” – all of which mean that “they retain juvenile features into adulthood”).  Female and larval GwBs sport “lanterns” or luminescent organs.  The individual that the BugLady held was just over an inch long, but the females of some species may be twice that.  Adult females are more likely than larvae to be found at the soil’s surface, and they tend to appear after a rain.

 

Adult females come topside to attract males.  Counter-intuitively, they communicate with males via pheromones (chemical “perfumes”) not light, which explains the male’s lovely, sensory antennae.  Eggs are laid in clusters on the ground, and the female encircles and guards them, glowing the whole time, until her death about a week later.  Eggs may not glow immediately but may become luminescent before hatching (the BugLady is wondering if the egg is glowing or the soon-to-emerge larva).  Larvae are active and eventually pupate in the soil.  Males live only briefly and do not eat, but larvae and adult females are unapologetic carnivores, mainly attacking millipedes (and maybe a few other small invertebrates) (it’s hard to come by a continuous supply of millipedes if you’re trying to raise GwBs).

 

OK – Bioluminescence.

 

Who has it?  Because of their similar approach to luminosity, GwBs were originally thought to be relatives of lightning beetles (Lampyridae), but our ability to do molecular studies has disproved that.  Research suggests that luminescence has been “invented” at least four times during the history of insects.

 

In the GwBs, the male is intentionally luminescent, a la lightning beetles; the larvae and females have paired photic organs on the sides of the segments and bands across the tops of the segments.  Some species have “headlights,” and those headlights may be a different color than the sidelights, but the BugLady can’t tell from her reading if that’s universal, and more work seems to have been done on tropical species than on domestic GwBs.  The side spots resemble the lighted windows of a passenger train, hence the term “railroad worm.”

 

How do GwBs pull it off?  Their light show is produced by a chemical reaction in which an enzyme called luciferase reacts with luciferin and chemical energy is converted to light energy (History Geeks will recall that some of the original friction matches were called “Lucifers”).  Different luciferase sequences produce different color lights (red vs green), and some species of GwBs make both.  Pretty slick.

 

Why do they do make light?  From a book called Volume 2: Morphology and Systematics (Elateroidea, Bostrichiformia, Cucujiformia partim) by Leschen, Beutel and Lawrence (2010) we learn that “The function of bioluminescence in the phengolids is not well understood.  The continuous glow of the head lanterns when the larva is walking suggests an illumination function, whereas the lateral lanterns may serve a defensive function.  A sudden flash might be used to dispel potential predators…… The dorsolateral locations of the lanterns in a walking insect suggests that the light is to be perceived by predators above them.  Aposematism (warning coloration) associated with distasteful properties is also a possible function for the lateral lantern light.”  The BugLady was going to delete the two “not-in-focus” pictures of an escaping GwB included here until she realized that you can see the green side lanterns as the critter heads underground.

 

Can they turn the light off and on?  The probable adult female we handled glowed constantly, and Marie has noticed that larvae at the bottom of the chunk of sod in the clear plastic “cage” glow, too.  Leschen, et al say that “At night, the shining head lantern can frequently pinpoint them, the lateral lanterns remaining dark.  Larvae were also observed with all lanterns switched on, making it easy to detect them at great distances” (easy for them to say – the BugLady turned out not to be a good GwB spotter).  A report on Phengodes fusciceps in the “Notes and News” section of the Entomological News, Volumes 17 – 18 (1906) states that “During the day they remained coiled and inactive; became active at night and intensely luminous; every segment, spiracle and line, apparently, showing a bead of greenish-yellow phosphorescent light.  This luminosity was present in the three specimens in the same degree, but the larger specimen, for five days, showed not a ray of light.  At the end of this period, it again became luminous.  This would indicate the insects controlled the luminosity.”

 

Older BugFans have permission to hum “Glow little glowworm, glimmer, glimmer…

 

To paraphrase the Bard, “O brave new world, That has such insects in’t!”

 

The BugLady

A camping trip without the work!

Family Camping Overnights @ Riveredge!

At Riveredge, we do our best to take the work and barriers out of going outside with your family. Our family overnights are no different – bring a tent and leave the rest to us!

We’ve polled staff members who have led family camping overnights about some of their favorite moments and memories.  Here’s a couple to give you a taste of the fun and good times our families have had…

Meet new friends!

“Last summer two separate families came to the overnight and they didn’t know each other. But as the families started to talk, it turned out they have so much in common. All their children are adopted. The families live very close to each other and their kids will go to the same school soon. The parents both had similar interests in biking and hiking and have been sight-seeing in similar places almost around the same times. I remember sitting at the table while the parents talked just in awe of how these two families connected and yet they had never met until RNC campout. I’d like to know if they still get together outside of RNC.”

Explore the night!

“Calling owls. I taught the families to make the barred owl call. We called together as a group and about 30 minutes later we had an owl calling back to us. We were all in our tents later and as we drifted to sleep we could hear two owls calling back and forth nearby. The families talked about it over breakfast in the morning.”

It’s easy and great for beginning campers or experienced folks who just want to take the easy road!

“A lot of parents said the family campout was their first time camping besides their backyard. The family overnight was a nice transition before camping at a campground. Riveredgehas the convenience of staff for questions, toilets, and indoor spaces incase of bad weather, and a breakfast in the morning.”

Join us on one of our upcoming Family Camping Overnights @ Riveredge!

Family Adventures: Family Overnight @ Riveredge

All Ages

Saturday, August 2, 5 pm – Sunday, August 3, 9 am  Theme: Creatures of the Night; led by Jessica Jens, Executive Director

Saturday, August 30, 5 pm – Sunday, August 31, 9 am  Theme: Exploring the Night Sky; led by Moriah Butler, Environmental Educator

Fee (per family): Member $45   Non-member $60

Join a Riveredge Naturalist for a unique opportunity to experience Riveredge after hours. Spend the evening exploring the trails, looking for night creatures, catching fireflies or relaxing at the campfire. Pitch your tent on the Riveredge lawn and slumber to the sound of the night choir. Bring a picnic supper, and in the morning you’ll enjoy pancakes with Riveredge maple syrup. Space is limited so register early. Each family is limited to one tent. Please note: At Creatures of the Night we’ll camp at Woodland Harvest; Exploring the Night Sky we’ll camp near the main building.

To register, visit our Summer Camp page and click on the “Register Now” button.  Hope to see you soon!

Bug o’ the Week – The Ants of CESA

Salutations, BugFans,

 

A few years ago, BugFan Marjie had a fantastic idea.  She wanted to get people out on the trails of the natural areas here in Ozaukee County (Wisconsin).  The plan – to staff different sites each year with interpreters, send people on their way with passports to be stamped at each destination, and finish the day with a big party at the Mother Ship – Forest Beach Migratory Preserve.  The event – Treasures of Oz.  Over the past five years, many thousands of people have made the acquaintance of county nature preserves that were not on their radar before.

 

This year, Marjie asked the BugLady to be part of the team at the Cedarburg Environmental Study Area (CESA), a property owned by the excellent Ozaukee Washington Land Trust, which sponsors Treasures of Oz (find descriptions and trail maps of all their preserves at owlt.org.  The CESA site hosts some phenomenal, six-feet-wide ant mounds, and the ant story needed to be told.  The BugLady was dubious – the general population, she has noticed, isn’t that inspired by bugs, and besides, due to a misspent youth, the BugLady is a tiny bit ant-averse.

ant mound cesa14 1rz

First off, what kind of ants are they?  BugFan Tom rounded up an ant guy in Mississippi who, of course, requested some ants.  The BugLady figured that she would place an old film canister (younger BugFans might have to Google “film canister”) on the top of a pretty active mound, and maybe some ants would climb in.  What could go wrong?  As soon as the canister landed on the mound, ants came pouring out, covering the top of the mound and covering the film canister, inside and out.  Now what?  The BugLady fished it off with a stick, managed to cap it, and rolled it around a bit to loosen the exterior ants.

ants cesa14 7rz

The ants were dispatched to Mississippi; the postal worker who asked if the parcel contained “anything liquid, fragile, perishable, etc.” didn’t ask specifically about ants.  Joe, the ant guy, made short work of the ID – the ants are Formica montana, in the wood/thatch/field/mound ant family Formicidae.  The genus Formica includes a bunch of mound-building ants that use different construction strategies in varying habitats.  Besides mounds, they are famous for defending themselves by spraying formic acid and by biting (often using the “bite-first-then-spray-the-irritating-chemical-into-the-wound” strategy).

 

Formica montana, a.k.a. the Prairie Mound Ant, is a pretty neat ant.  While they are important in prairie ecosystems, they are also wetland specialists, and the ground in much of the CESA site is damp.  PMAs build mounds in peaty, wetland soils, and their lives are governed by the water table.  While their prairie relatives may tunnel five feet into the earth, nests in wetlands are shallower, and ants must be prepared to move up above ground level, into the mound, if the water rises.  Considering all the rain we’ve been having, they’ve probably been spending lots of time “upstairs.”

Formica_Wisconsin_headrz       Formica_Wisconsin_siderz

Mounds are formed when ants tunnel into the soil and bring particles to the surface to dispose of them; ants move more dirt than earthworms and are valuable soil mixers and turners.  Young mounds are steep-sided and about 12 to 15 inches tall, and they often have vegetation on top.  As the population increases, the ants build out because, in wetlands, they can’t build down.  One source said that a large mound might have 6,000 ants in it, but the BugLady thinks that number is way low for some of the mega-mounds at CESA.  The tops of PMA mounds may have fifty or more entrances, and the mounds themselves consist of a honeycomb of tunnels and chambers for food and young and for workers to rest in, and the tunnels also effect oxygen exchange.  The average mound takes about six years to build and lasts for about 12 years, but some have been clocked as old as 30 years.  A colony may get larger by “budding’ – forming a smaller colony nearby and then growing toward it, and PMAs may construct small, seasonal feeding mounds.  Mounds are often found growing near red-osier dogwood shrubs; this sun-loving shrub of early succession tolerates the same kinds of soil as the ants – soggy, but not permanently soggy.  The dogwood is also a portent of future shade trees – bad news for the ants.

 

The mounds are solar collectors.  Some Formica ants cover the tops of their mounds with bits of vegetation, and other ants actually plant grass there.  PMA mounds are built in the open or on woody edges, and the tops are kept clear of anything that generates shade.  The ants actively clip any plant that tries to grow.  The domed shape makes mounds more efficient at catching the sun’s rays at the start and end of the day.  PMAs like it warm and humid (100% humidity is just fine with them), and they move their larvae and pupae around to nurseries with the optimal climate.

 

What do all those ants eat?  Protein, in the form of insect larvae and pillbugs.  Lots of carbs.  Their main carbohydrate is honeydew, sugar water that they harvest from aphids and treehoppers that they “farm.”  In close proximity to one mound at CESA were dense herds of ant-tended aphids on dogwood flower/fruit heads, and smaller bunches of ant-tended treehoppers (and their astounding nymphs) on goldenrod stems.  In return for the ants’ protection, the bugs allow ants to “milk” them; stroking the bugs’ abdomen induces them to exude drops of honeydew.  Workers find their way to distant food sources by following “trail pheromones” left by other workers.  The BugLady saw the protein-rich, spore-bearing head of a horsetail/equisetum plant by one nest entrance and guesses that the ants might feed on that, too.

ants, treehppr adults cesa14 6rz

Ant with treehopper

PMAs are very territorial, both with PMAs from different mounds and with other species.  They generally out-compete non-PMAs, and they carve up the habitat neatly so that multiple PMA colonies can live side-by-side without using up the food supply.

 

Ant mounds have generated a new art form.  For a picture of a plaster cast of what’s under the surface, see http://en.wikipedia.org/wiki/Ant_colony#mediaviewer/File:Ant_Nest.jpg.  If you Google “Ant Mound Art” or “Cast aluminum ant tunnels,” or some such, you can see lots of examples.  The ants don’t survive the artistic process (animal lovers have protested).  Many of the mounds so treated have been fire ant mounds.

 

In the end, 120 people visited CESA during the recent Treasures of Oz event, and many left thinking more highly about ants than when they arrived (except for the jerk who walked along poking a hole in each mound he saw with his walking stick).  Nest repair is what ants train for, but it takes time and energy, and recent pounding rains have given them plenty of work.  If BugFans decide to visit the ants of CESA (right now, there is a Bluet Bonus – gazillions of marsh bluet damselflies dripping from the vegetation and making more bluets), they should remember that along with the mound-top itself, there’s a zone of activity at least a foot wide around the base of the mounds, and tunnels that extend outward from the base, under the soil), and active trails to outlying “herds.”  BugFans who stand in awe at the edge of a mound will soon find themselves doing the “ant dance.”

 

Here’s a good article about PMAs: http://images.library.wisc.edu/WI/EFacs/transactions/WT1981/reference/wi.wt1981.jwbruskewitz.pdf

 

Bravo, Joe, at the Mississippi Entomological Museum, for the ID and the super-macro pictures, and thanks, Southern BugFan Tom.  It does, indeed, take a village.  If you’re ever in town……

 

Bravo, Yankee BugFan Tom, for putting in a day of ant-education.

 

Bravo, Marjie and OWLT.

 

Bravo, ants!

 

The BugLady

Bug o’ the Week – Virgin Tiger Moth

Howdy, BugFans,

 

What a classy-looking moth!

 

It’s a Virgin tiger moth (Grammia virgo) (probably), a member of a large group of sometimes dramatically patterned moths who whose fuzzy offspring are called “wooly bears” or “wooly worms” (the familiar, rust-and-black, “weather-predicting” wooly bear caterpillar is the offspring of the Isabella Tiger Moth).  Depending on whose book you read, VTMs might be placed in the family Arctidae or be listed as a subfamily in the family Erebidae.  Arctidae is the older designation; Erebidae is a newer and not-universally-embraced family that combines the owlet, tiger and tussock moth families.

 

The BugLady is content to let the lepidopterists duke it out; wherever it lands, the VTM is a tiger moth.  Tiger moths are unusual among moths because they have on their thorax tymbal organs, which can be used to produce ultrasonic sound (more about that in a sec), and tympanal (hearing) organs (if you’re going to make sound, it’s nice to be able to hear sound).  “Ears” are somewhat more common in moths, but some (maybe all) tiger moth caterpillars can hear, too, picking up sound through some of their hairs.

 

As far as their predators are concerned, the tiger moth bunch packs a gustatory wallop, both as caterpillars and adults.  TM caterpillars, which are not generally considered plant pests, are fairly catholic feeders on low herbaceous and woody vegetation like plantain, clovers, bedstraw (VTM caterpillars especially like bedstraw), goosefoot, lettuce, and willow, and the toxic chemicals they consume from their food plants are off-putting to predators.  The toxins may remain with them through metamorphosis and into adulthood, and the “toxic edge” continues when females transmit protective chemicals to their eggs.

 

There are about a dozen confusing Grammia tiger moths, and their caterpillars are also difficult to tell apart.  Beneath the VTM’s snappy exterior lies a surprise – brightly-colored hind wings.  Most VTMs have rosy hind wings with black splotches, but a small number of moths wear yellow.  Here’s a moth with its wings open http://bugguide.net/node/view/246414/bgimage, and here’s the caterpillar http://www.pwconserve.org/wildlife/insects/caterpillars/virgintigermoth.html.

 

Tiger moth species get the word out about their inedibility both with their striking colors/patterns (aposematic/warningcoloration) and/or by using their characteristic ultrasonic emanations to startle bats, to warn bats to stay away, or to “jam” the bat radar.  Researchers John Ratcliffe and Marie Nydam studied these “multimodal signals” – visual signals that protect moths during the day and auditory signals for those active in the night.  Multimodal signals might simply deliver a more comprehensive message to a single predator, or they may address multiple predators in the languages they understand.  The researchers correlated the signaling style with the flight periods and the nocturnal/diurnal habits of 26 species of tiger moth.  They found that tiger moths that were active in spring and in the daytime were brightly colored and used visual cues to deter birds; species that emerged later in summer and flew at night used clicking to discourage bats.

 

VTMs can do it all, and more!  They are late season moths (therefore more worried about bats than birds), but they are abroad at any time of the day or night, so they have a striking pattern on the fore wings (the markings of the genus Grammia are said to have given the group its “Tiger Moth” nickname), flashy hind wings (when mistreated, they play possum, flipping over, curling up their abdomen, and showing off their hind wings), and they can click at the bats at night.  In case there are any predators left undecided, VTMs also produce a defensive chemical foam.  Wagner, in “Caterpillars of North America,” says, “Adults, when gently squeezed, may bubble generous amounts of their yellow “blood” out of the front corners of the thorax, yielding a frothy mass that contains alkaloids that the caterpillar has consumed.”

 

Their taste (and their distinctive odor) have elicited comment for some time.  In 1859, the very not-PC Thaddeus William Harris wrote in “A Treatise on Some of the Insects of New England: Which are Injurious to Vegetation” that “The largest and most rare of these moths is the Arctia virgo, or virgin tiger moth.  On account of the peculiarly strong and disagreeable odor it gives out, it might, with greater propriety, have been named the stinking tiger moth.”  In “The Life of North American Insects,” also published in 1859, Jaeger and Preston state that “The Virgin Tiger Moth (Arctia virgo) is one of the handsomest and largest of this genus, but on account of its fetid odor it is very disagreeable to handle. 

 

Sounds and scents figure into tiger moth courtship, too.  Females “call” males by emitting a pheromone (“perfume”) plume that males can sense with their antennae.  Males send out ultrasonic signals to females before releasing their own chemical signals, and when he’s getting close to her, he may click and she may answer.  When males of some species emit certain odors, it demonstrates to the female that he can give her the chemical that will protect her eggs.  There is one generation per year, and VTMs overwinter as caterpillars; waking up to continue eating in spring and eventually incorporating some of their own body hairs into their silken cocoons.

 

The VTM is found in woodland and wetland edges, clearings and fields east of the Rockies, though it’s uncommon in the far South.  Its internet presence consists mainly of its inclusion on lists, surveys and museum collections, but because of its general spiffiness, there are lots of photos and even some artistic renderings.

 

No, the BugLady didn’t see an explanation for the “Virgin” part of the name.

 

The BugLady

How the Boundary Waters Can Change Your Life

Riveredge hosts adventure trips every summer.  This year, we still have some spots open for our Boundary Waters Canoe trip.   Join us (but make sure to register by June 23rd)!  Not only will you have a great time, meet new friends, learn more about yourself and all you are capable of, it may also just inspire your future choices.  Here’s how it did just that for one young person, Elizabeth Garret.

 

“The Riveredge Nature Journeys Questers program is a fantastic way to discover the unknown world of nature and wildlife. The trip to the Boundary Waters Canoe Area (BWCA) had an unexpected impact on my life. The first year I attended a Questers trip, I had minimal experience with the outdoors. It was my first long camping trip, and I had no idea what I was getting myself into. While there, I discovered a whole new side of myself that I had no idea existed – a passion for the environment. I found a new love and appreciation for the serenity and peacefulness of nature. On one of the last days I remember thinking to myself how amazing it would be to work at on outfitter in the BWCA for a summer or two. Little did I realize that exact opportunity opened itself up to me. I recently accepted a job working at an outfitter for this summer.

I also didn’t realize that this single trip would inspire me to look at colleges with an environmental emphasis. I now attend Northland College, which is an environmental liberal arts college, studying Environmental Geosciences. I am also leading a camping trip for new students next fall and becoming certified as a Wilderness First Responder. Riveredge and all of its programs can open many doors. For me, it changed the whole direction of my life. It has taught me life lessons that cannot be found in a classroom or in a textbook. I would recommend to anyone to take advantage of the wonderful leaders and opportunities the Questers offer. The experience will change your life.”