Author: rbuchholz

Howdy, BugFans,

The BugLady was chasing a very jumpy Eastern Comma butterfly around her driveway (with a camera) the other day.  Commas are in the Brushfoot family, Nymphalidae, in the genus Polygonia (Greek for “many angles” – remember high school geometry?), a group that’s called, for obvious reasons, “anglewings.”  She found an article that dubs them “Butterflies That Punctuate,” because of the distinct, white/silver mark on the underside of the hind wing.  Anglewings are among the last butterflies abroad in fall and the first in spring (and sometimes in-between).  What follows is a major overhaul of a BOTW from 2009.

In general, insects spend just a few months (or less) in their adult skins, and most adult insects die with the first frosts, leaving the next generation behind in the form of eggs or pupae (or, less commonly, as nymphs or larvae).  Wisconsin’s anglewings overwinter as adults (as do members of the genus Nymphalis, which includes the Mourning Cloak).

Adults spend the winter tucked into spaces called hibernacula (singular – hibernaculum) – cracks and crevices in rock piles and tree bark or under eaves.  They may emerge on an especially warm winter day and then shelter again.  Because their blood contains glycerol – antifreeze – their tissues avoid cell damage while withstanding the winter’s cycles of freezing and thawing.

Some species of anglewings produce two generations a year in Wisconsin and others have a single brood.  Second-brood anglewings that emerge in late summer to fly in fall are seven or eight months old by the time they breed during the following spring – supercentenarians by butterfly standards.  Summer and winter adults have somewhat different coloration; the top surface of the hind wing is more uniformly dark in the summer butterflies, the “umbrosia” form.  Just as their winter counterparts doze through the cold weather, the summer forms may become dormant in response to the heat.

The lack of flowers at the start and end of their flight period bothers these butterflies not at all; they have alternate menu options.

Two common anglewings in Southeastern Wisconsin are the Eastern Comma and the Question Mark; (check out Mike Reese’s Wisconsin Butterflies website for information about the state’s commas: https://wisconsinbutterflies.org/butterfly/subfamily/17-true-brushfoots.

Birders who are diving into Gull identification are advised to study the Herring Gull in all of its ages/stages/plumages in order to compare them to other gulls (FYI, there are many different kinds of gulls, but there is no species called a Sea Gull.  If you’re not sure what kind it is or are referring to them collectively, just saying “gull(s)” will do.  Different pulpit).  Anyway, in taking on the anglewings, learning the Eastern Comma seems like a good place to start (the BugLady has no doubt that she has some mislabeled comma pictures in her files).

The EASTERN COMMA (Polygonia comma) is also called the Hop Merchant.  Hops are one of its larval food plants, and hop growers historically considered the metallic flecks on the chrysalis http://bugguide.net/node/view/924296/bgimage to be a portent of what their crops might bring at the market.  Silver markings meant low prices; gold meant high.

It’s a wary butterfly, one that flies swiftly and erratically, and when it ducks into the vegetation and perches (often head-down on a tree trunk), its dead-leaf/wood-grained underwings make it tough to see.  Eastern Commas will sit on people, crawling around until they find the right exposure and then basking.  Douglas and Douglas, in Butterflies of the Great Lakes Region, report that Eastern Commas will seek sweat on people’s skin, often searching disconcertingly close to the eyes of their human perches.  Males defend their “pied a terre” aggressively.

Eggs are laid, sometimes in stacks, on the underside of host plant leaves.  Eastern Comma caterpillars feed at night, on nettles, elm and hops.  It’s one of the species that seems to have broadened its palette as European settlers brought hops and non-native nettles (an important fiber plant) to the Northeast.  The caterpillars, according to David L. Wagner in the awesome Caterpillars of Eastern North America, will select a leaf and fold the edges under with silk to make a daytime shelter.

Adults sometimes visit flowers, but they generally sip from sap drips on tree trunks, imbibe the juices exuded by rotting fruits and berries, and absorb salts and minerals from animal droppings and from the ground (each time it landed, her driveway comma extended its proboscis and probed the gravel for minerals).

The Eastern Comma is sometimes described as an inconspicuous butterfly, but the BugLady humbly disagrees.  While it can be extraordinarily well-camouflaged, an individual sunning itself on the dead leaves of the forest floor glows like a small flame.

QUESTION MARKS (Polygonia interrogationis) are handsome, medium-to-large sized (wingspread about 2 ½”) anglewings that have a white/silver question mark on the underwing – though Samuel Scudder preferred the name “Violet-tip” (because of the edges of the winter form’s hind wings) and nineteenth century American entomologist Thaddeus Harris called them the “Semicolon butterfly” (it’s all about perspective).  Their underwings may be leafy-looking or be a fairly uniform in color.

Male Question Marks are described as “pugnacious,” flying out from sunny perches to greet visiting females and to deter rival males (and sometimes other intruding insects and even birds).  Like other anglewings, they will land on people who are standing really still (especially in the sunlight) and probe for sweat.

They feed on tree sap, rotting fruit, and nutrients in soil, carrion and dung; females are more likely to nectar from flowers than males are.  According to Robert Michael Pyle in The Audubon Society Field Guide to North American Butterflies, anglewings are prone to intoxication if the fruit they sip from has been fermenting in the sun too long.  They are “quiet drunks” – an inebriated Question Mark may pose for pictures and finally tuck in its legs and play dead.

Question Marks have two broods each year in our neck of the woods.  Females lay their eggs in stacks under the leaves of hackberry, hops, nettle and elm, and while they’re not super-gregarious, the resulting caterpillars may tolerate nearby siblings.  They don’t make leaf nests.  Like other anglewing caterpillars, Question Mark larvae are decorated with non-toxic, branched spines called scoli (singular – scolus), including a pair of spines on their head http://bugguide.net/node/view/1129753/bgimage.

Along the Atlantic coast, Question Marks are both residents and migrants, so early spring sightings could either be recently-awakened or recently-arrived.  Their migratory status in Wisconsin is unknown, but migration is a handy arrow to have in your quiver where the winters get a little brisk.

The BugLady’s searches took her, once again, to the Butterflies of Massachusetts website, where nearly two centuries of data are thoughtfully analyzed and where changes in butterfly populations with shifting land use patterns/habitat changes are documented.  For lots of information, see http://www.butterfliesofmassachusetts.net/eastern-comma.htm and http://www.butterfliesofmassachusetts.net/question-mark.htm.

View the Eastern Comma and the Question Mark side-by-side at http://trekohio.com/2013/04/24/butterflies-that-punctuate-the-eastern-comma-and-the-question-mark/ and

http://www.naba.org/chapters/nabambc/frames-2species.asp?sp1=Polygonia-interrogationis&sp2=Polygonia-comma.

In the “Wow – Who Knew??” category see https://en.wikipedia.org/wiki/Glossary_of_entomology_terms

And here’s a jumping spider follow-up: http://www.npr.org/sections/thetwo-way/2016/10/14/497931790/a-spider-across-the-room-can-hear-you-study-finds.  Thanks, BugFan Laurel.  “The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ (I found it) but ‘That’s funny…‘”–Isaac Asimov

Kate Redmond, The BugLady

Bug of the Week archives:
http://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/

Salutations, BugFans,

The (outdoor) bug season is winding down (the BugLady has been Mushroom/LichenLady, of late), but there are still some insects to be found. She was excited to see a pair of walkingsticks recently, so here’s an updated BOTW from the fall of 2008 (new words, new pictures) Yes, walkingstick insect is a single word; a walking stick helps you balance when you hike.

Like mantises, walkingsticks were formerly classified in the grasshopper Order (Orthoptera); and, like mantises, walkingsticks are now in their own Order, the Stick Insects or Phasmatodea (from the Greek “phasma” meaning “apparition” or “phantom”). Because of their unique shapes and habits, they’ve collected common names like Devil’s darning needle, Devil’s/Witch’s riding horse, and prairie alligator. There are about 3,000 species worldwide, and they’re most diverse in the tropics. The Lord Howe Island stick insect, of previous BOTW fame, is a walkingstick.

Walkingsticks are generally green or brown (a few species can change color slowly, and there’s one in Madagascar that’s bright blue). The largest North American species can grow to a whopping 7”, and one tropical species may reach 14” (22” with antennae and front legs out-stretched). Northern walking sticks (Diapheromera femorata), the only species in northern North America, is 3 ½” to 4” in length (males tend to be smaller). Most species in the US are wingless; insect legs (and wings) are attached to its middle section (thorax), and a walkingstick’s thorax comprises an impressive one-half of its body length. A walkingstick that loses one of those spectacular legs – they may sacrifice a leg if a predator grabs it – may be able to regenerate it, completely or partially, depending on species and age. The abdomen is tipped with a pair of cerci (claspers) that are sensory.

Walkingsticks are terrestrial – if you see a similar critter in the water, it’s an (unrelated) water scorpion.

Shy and nocturnal, they are most active between 9 PM and 3 AM, and, says one study, they have “screening pigments” in their eyes that act to block excessive light of daytime. They graze on the leaves of a variety of deciduous forest trees, starting on low shrubbery as tiny nymphs and moving to mature trees as adults. During a population boom, they can do some serious damage. The BugLady can’t picture walkingsticks occurring in numbers sufficient to defoliate a tree, since she rarely sees more than two or three a year. Damage is localized, geographically, simply because the wingless walkingsticks don’t cover a lot of ground.

There are two reasons for camouflage, to hide and to hunt, and walkingsticks are world-class hiders that practice “crypsis” – camouflage plus mimicry. In addition to their physical appearance, walkingsticks use “behavioral camouflage;” during the day they extend their front and rear legs to the fore and aft of their body and remain motionless or sway slightly in the breeze for hours.

Turns out that despite one of Mother Nature’s better camouflage jobs, some predators aren’t fooled; walkingsticks are spotted and eaten by a variety of songbirds, rodents and mantises, especially in boom years. They are attacked by several parasitic wasps and flies, including a fly that oviposits on leaves and parasitizes a mantis that accidentally eats its egg. Two species of Florida walkingsticks have added chemical warfare to the usual arsenal of passive defenses, squirting a highly irritating liquid into the face of a potential predator and earning the nickname “Musk-mare.”

Northern walkingsticks reproduce when they mature in late summer/early fall. As females negotiate the treetops in early autumn, they drop eggs (about 150) that free-fall to the ground and overwinter in the leaf litter http://bugguide.net/node/view/604456/bgimage. Their eggs mimic seeds, which may offer some protection from parasites. These will hatch in spring – or in the one after that – although if the winter and spring have been especially dry, the egg will not soften enough to allow the nymph to emerge. According to the Forest Service’s “Forest Insect and Disease Leaflet #82,” “As the cycle in the north is 2 years long, even-year and odd-year broods have developed. In some localities both broods are nearly equal in numbers, but in others they are unequal. For instance, in Minnesota even years are “off years,” while in Wisconsin and Michigan odd years are “off years.”

Metamorphosis is Simple/Incomplete – the newly-hatched nymphs resemble the finished product (http://somethingscrawlinginmyhair.com/2016/08/31/northern-walkingstick/), simply growing and adding adult parts as they go along. Nymphs start out green, and get twiggier-looking in color and texture as they molt, hanging on to the underside of a leaf. Adult males tend to be brown, and females green and brown. Northern walkingsticks sometimes practice parthenogenesis (virgin birth), in which case their offspring are all females.

Like mantises, walkingsticks are interesting, but high-maintenance, pets, requiring careful handling and a variety of fresh tree leaves daily. They’ve been known to live a year in captivity.

The BugLady was casting about for one final interesting factoid with which to finish this account, and she discovered two, in “The Handy Bug Answer Book” by Dr. Gilbert Waldbauer:

First, parental care is necessarily absent in a species where Mom drops her eggs to the ground from great heights, and the forest floor is fraught with dangers for the hapless eggs, including from cuckoo wasps that search for walkingstick eggs to parasitize. Because a portion of the outside of each egg is edible, ants carry the eggs below-ground to their nests. Their nibbling does not damage the interior of the egg, and when the tiny (a few millimeters long) walkingsticks hatch, they are allowed to exit the ant hill.

[OK – extra credit time: the tasty area on a walkingstick egg is called a capitulum. The capitulum on an insect egg is, wait for it, mimicking a similar tasty and nutritious area called an elaiosome on a plant seed that depends on ants for distribution. Ants haul the seeds back to their nest, eat the edible part, and toss the rest into their waste heap, which happens to be a great growing medium. Seed dispersal by ants is called myrmecochory, and plants and animals that enjoy a partnership with ants are called myrmecophiles.]

The second factoid includes some “adult content,” and the BugLady requests that you cover the eyes of impressionable children, if you know any. Fidelity is rare in the insect world, and there are a number of strategies that males of some groups may use to ensure that the object of their affections does not court another. Some male walkingsticks are known to, ah, remain “in the embrace” of a female long after sharing bodily fluids with her, becoming what Waldbauer calls “living chastity belts” [and from which convenient position, males will also fight off rival males] In fact, the, um, endurance record for copulation for the insect world seems to be held by walkingsticks.

One member of the genus Diapheromera hangs on for 136 hours; another walkingstick species stays coupled for 3 weeks.

OK – Seventy-nine days.

The BugLady

Salutations, BugFans,

Recently, the BugLady sent a series of not-so-good pictures to her go-to spider guy, BugFan Mike, and his explanation inspired this episode.  Thanks, Mike, as always.

The BugLady’s mailbox spider is a Bold/Daring jumping spider (Phidippus audax), but she has photographed other species, including the Brilliant jumping spider (Phidippus clarus) (“clarus” means “clear or bright”) on vegetation in her field.

Jumping spiders (family Salticidae) make silk, but they don’t make trap webs, preferring to spot their prey from afar and leap on it (they can cover 50 times their body length in a single bound).  Jumping spiders have outstanding eyesight – better than dragonflies, insist some sources.  The large, center pair of eyes faces straight forward, giving the spider excellent resolution, and they have good color vision.  Since they are not tied to a single location by a web, they spend a lot of time on foot (they can remember visual landmarks and relocate their nests) or head-down, near the top of a plant, like a sailor in a crow’s nest.  Whether they spot their prey from a perch or find it during a walk, they can spin a dragline when they jump – no “working without a net” for them!

Brilliant jumping spiders, a.k.a. Red and black jumping spiders, can be found from coast to coast but are more common in the eastern half of North America.  Creatures of tallgrass prairies and open spaces, these spiders not only sit near the tops of plants, they put their nests (both males and females create nests called hibernacula) and egg sacs there, too.  They can get away with being conspicuous because of their large populations.

We all know that spiders are devoted carnivores, but…..  Turns out that there is a species of jumping spider in Central America that is mostly vegetarian (though it eats the occasional ant and it dabbles in cannibalism), and it’s not uncommon for juvenile jumping spiders of a variety of species to consume nutrient-rich nectar (from extrafloral nectaries, of previous BOTW fame) and pollen.  After a successful hunt, a Brilliant jumping spider will settle down to feed (it can subdue earwig-sized prey), and it will eat more slowly if it is very hungry.  Because of its size (large, for a Jumping spider) and numbers, P. clarus has been suggested as a biological control for some species of plant bugs (though its tendency towards cannibalism makes mass-production in the lab difficult).

In many spider species, an ardent male approaches the larger female cautiously and departs hastily once the deed is done (she, after all, needs protein).  But, the pictures that the BugLady sent to BugFan Mike, taken in early July, showed a male P. clarus hanging around a milkweed leaf that was curled up and webbed together to make a nest, with a female inside.  What, asked the BugLady, was going on?

Said Mike, “P. clarus males actually do pre-copulatory mate guarding. They mature earlier than females, and locate and guard a pre-adult female. Then they mate with her as soon as she molts to adulthood.”

When boy meets girl, he initiates courtship by waving his legs and flashing his iridescent mouthparts (chelicerae) at her and by vibrating his abdomen against the substrate.  He reaches out to touch her, and she either parries or accepts his advances.  If she’s ready, romance ensues.  Females evaluate the vibrations; a male with longer legs vibrates more rapidly, indicating that he’s large.  He assesses her age and size based on the pheromones she leaves on the silk she spins.  Both males and females show a bias toward picking the biggest possible mate (a large male looks more “fit” to her and a large female looks “eggier” to him).

He also vibrates to intimidate possible rivals.  Face-offs between males involve ritualized signals and responses, and physical encounters are sumo-esque – lots of pushing, some grappling.  Research shows that males that have previously won male-male encounters tend to win again, and losers lose again, but size, and what BugFan Mike calls “home field advantage” factor in, too.  When females interact, it’s less “scripted” and can be fatal.

What about those child brides?  Early in the season, a wandering male may come across a hibernaculum occupied by a sub-adult female and either co-habit or build a nest on top of it, protecting the female from other males until she matures, mating within the nest.

Later in the season, males may find non-virgin females and initiate “extra-hibernacular” (the BugLady just made that word up) liaisons.  Females that mate a second time often require a more earnest courtship (because females that have been protected within their nests generally mate with whoever’s protecting her, one study suggests that she may be “trading up” the second time, looking for a bigger male).

Females lay a clutch of 125+ eggs.  The spiderlings stay in the nest for about a month after they hatch; the female guards the nest http://bugguide.net/node/view/224274/bgimage and dies shortly after the young leave it.

For a video of P. clarus shots see http://www.rkwalton.com/salticids/Phidippus_clarus.php.  Bonus points if you can ID all the bird calls: It’s an interesting site to explore http://www.rkwalton.com/sitemap.php.

For a thorough, well-illustrated biography of P. clarus, see http://peckhamia.com/peckhamia/PECKHAMIA_113.1.pdf

For a story about some moths that fool jumping spiders by mimicking them, see: http://news.nationalgeographic.com/news/2007/02/070214-moths-mimic.html.

Kate Redmond, The BugLady

Bug of the Week archives:
http://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/

Greetings, BugFans,

The BugLady confesses that she and her camera walk past lots of small flies without stopping because there are already too many flies in her “X-files” (she labels unidentified insects as “x beetle 7” or “x fly 16”).  But – here are some “x-flies” that she was able to track down – or stumble upon by accident.  Once again, we celebrate the bugs that are neither big enough nor bad enough nor good enough nor flashy enough to inspire study – or even, in many cases, to have been assigned a common name.

CHRYSOPILUS SNIPE FLIES: The BugLady is constantly surprised by the shapes and colors that Snipe flies (family Rhagionidae) come in (this summer, she observed a Rhaggio snipe fly darting about on a leaf top, bowing its head down to the leaf and pushing its face over the surface, stopping to peer down through a small hole in the leaf – a story for a future BOTW, if she ever figures it out).  These small, black, big-eyed flies, the clear-winged Chrysopilus proximus and the smoky-winged C. quadratus (probably) are, surprisingly, in the same genus as the splendid Golden-backed snipe fly, of previous BOTW fame (“chrysopilus” means “golden hair”).  Chrysopilus snipe flies are distributed (more-or-less) world-wide.  Their larvae live in rotten wood, in the water, or in very moist soils, where they eat tiny invertebrates or insect eggs.  Chrysopilus quadratus larvae live in rotting wood.

Those amazing eyes!  Chrysopilus quadratus males are darker than females, and their eyes touch each other; females are honeybee-colored, with widely separated eyes.  They have a square-ish spot on each wing.

EUARESTA FLY: “Fruit fly” evokes images of tiny Drosophila melanogaster flies (family Drosophilidae, a.k.a. Vinegar flies) hovering over fruit bowls, of biology experiments, and of populations of red-eyed, minimally-chromosomed escapees haunting the hallways and snack rooms of scientific institutions.  The name “fruit fly” is more properly claimed by members of this fly’s family, Tephritidae.  This little fly with the macramé wings is Euaresta bella (probably).  The genus Euaresta is endemic to the New World, and nine of its fifteen species are found in North America.  Euarista bella is one of two species that have been exported on purpose.  Why?  Because the host plants of the various species ofEuarista are common ragweed, giant ragweed, and cocklebur, which are unwanted in many of the places they grow.

Euarista bella specializes in common ragweed, overwintering in the seeds and pupating in spring.  The adults feed on ragweed juices and on honeydew (aphid by-products that drop onto leaves and are subsequently harvested by various wasps, flies, etc.).  You would expect that wings like that would be used in ritualized behavior, and you’d be right – courtship includes wing-waving along with head-butting and proboscis-touching.

FLUTTER FLIES (really!) are somewhat related to the Tephritidae but are in the family Pallopteridae.  It’s a very small family with only 70 species, nine in North America.  Their other common name, Picture-winged flies, is borrowed from another fly family, the Otitidae/Ulidiidae.  Not a lot is known about the biology of the Flutter flies; some of their larvae are vegetarians and some are parasitoids of the larvae of a variety of wood-boring beetles.  Larvae are found under tree bark or in flower buds and plant stems, and adults can be seen on flowers and low branches.  Yes – “Flutter flies” because they vibrate their strikingly-patterned wings.

The BugLady read about a British study that suggested that some Flutter fly larvae (they call them Trembling wing flies) may feed on fungal mycelium under maple bark in the absence of beetle larvae.

Anyway, meet Toxonerva superba, sometimes listed as Toxoneura superba and sometimes as Palloptera superba.  Toxonerva means “bow-shaped vein/cord” a reference to the wing veins; superba because, as bugguide.net says, “It’s a superb looking little fly.”

PARHELOPHILUS SYRPHID FLY: Syrphid/Hover/Flower flies, of previous BOTW fame, are masters of deception that wear the colors of bees and wasps in order to discourage predators.  Adults are harmless nectar and pollen feeders, but their offspring, depending on the species, eat insects (some are prized for the attention they pay to aphids) or eat decaying organic matter on land or in the water.  The larvae of PARHELOPHILUS are aquatic and are among the species nick-named the “rat-tailed maggots” because of a breathing tube at the tip of their posterior that they to the surface from the mud or debris at the pond floor.

Parhelophilus syrphids (the BugLady isn’t going to guess at the species) are found throughout most of the continent.  Their larvae like to live among the cattail rhizomes and can tolerate water with some pollution and a low oxygen content.  The BugLady found this beautiful fly a few feet from the edge of what probably was its natal pond.  They are often seen sunning themselves.

The BugLady recommends this TED talk: http://www.npr.org/2016/09/30/495216034/how-do-we-embrace-all-kinds-of-nature.

Kate Redmond, The BugLady

Bug of the Week archives:
http://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/

Hey, BugFans,

Isn’t this an awesome insect?  It’s got an inch-and-a-half long body, a three inch wingspread, and a four inch “leg-spread!”  The BugLady looks forward to finding them in late summer, often on walls that they have fetched up against as the night ended, and where they will wait out the daylight.

In an early BOTW about crane flies, the BugLady treated them generically.  (https://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/crane-fly-redux.cfm).  They are, after all, a large bunch of exceedingly long-legged, “horse-faced,” somewhat similar-looking flies, many of which look like mosquitoes on steroids (but they’re harmless).  Naturally, it’s more complicated than that.  In this case, there’s an extra designation under Order Diptera called the “infraorder Tipulomorpha” (“crane fly shape”), and this infraorder includes five families – the “classic “Large crane flies” (Tipulidae); Winter crane flies (Trichoceridae), of previous BOTW fame; Limoniid Crane Flies (Limonidae) the largest family numerically; Cylindrotomid Crane Flies (Cylindrotomidae), the smallest family; and the star of today’s show, a Pediciid Crane Fly in the family Pediciidae (the “hairy eyed” crane flies).

They’re all in the order Diptera – “two wings.”  A fly’s membranous, flying wings are attached to the enlarged, middle segment of its thorax; the final thoracic segment bears two knobs called halteres that are actually its former second set of flying wings, highly modified and used to maintain balance in flight.  For a (very) thorough discussion about this fascinating adaptation, see https://en.wikipedia.org/wiki/Halteres.

There are an estimated 15,300 species in Tipulomorpha worldwide and possibly that many more to discover.  The Giant eastern crane fly (Pedicia albivitta) (“albivitta,”meaning “white band/stripe,” for the markings on the abdomen) is one of about 150 species in its family in North America (500 globally), and is one of the largest crane fly-ish species on the continent.  It’s found from Minnesota east through southern Canada and south to North Carolina.

According to bugguide.net, Tipula is Latin for “water spider”/”water fly.”  Crane flies, of course, because of their long (fragile), crane-like legs (they were the only type of insects, in a school insect collection the BugLady once did, that were allowed to have fewer than six legs).  “Hairy eyed crane flies” because, although not visible to the casual observer, there are short hairs between the eye facets.  “Horse-faced” because their longish snout (rostrum) bears a bump (called a “nasus”) (nose), and the nasus bears the maxillary palps, which are sensory and manipulative appendages http://bugguide.net/node/view/1011946/bgimage.

What do the adults eat?  As The Dragonfly Woman puts it in her blog, “Crane flies, on the other hand, eat nectar or don’t eat at all.  As a result, they have thicker, blunt mouthparts with all kinds of crazy looking doodads sticking off them or no mouthparts at all.” (https://thedragonflywoman.com/2010/04/21/giantskeeter/).  Adult GCFs are non-eaters.

Their larvae eat, though.  Crane fly larvae look a bit like bloated earthworms; some are aquatic carnivores or detritivores, and others live a bit higher, but not much drier – in forest floors, in damp areas at the edges of wetlands, or in the roots of grasses and crops (where some herbivorous species are unappreciated).  The GCF larva is carnivorous, feeding on small invertebrates in the muck of stream bottoms, in wet soil, cold springs, and in mosses at stream edges.  Both adult and larval GCFs provide food for invertebrates and vertebrates alike.

As seasoned BugFans know, the BugLady is always on the lookout for interesting sources to quote.  In the course of her research, she found the GCF mentioned in a diverse collection of sources like J. G. Needham’s account in The Crane-flies of New York: Biology and Phylogeny (1920) (“The larvae of P. albivitta live in cold springs and beneath saturated moss at the edge of streams.  The writer has never succeeded in rearing this species to the adult condition.”).  The Carbon Dioxide of Soil Air (1920), and Bryophyte Ecology (2015) ([the Pediciidae] “resemble craneflies. Pedicia … ((now placed in Pediciidae)) is one of the craneflies found among mosses as larvae … in some streams in the Appalachian Mountains, USA (Glime 1968).  Hilsenhoff (1975) reported the genus in Wisconsin, USA, where it includes mosses among its substrata.”), along with the usual suspects.

Bonus fact: – you can tell the gender of a crane fly easily, even in flight.  The abdomen of males have a clasper-type tip, and the females’ abdomens are pointed (ovipositor).  Males are said to have a bouncy flight, and females a no nonsense, direct flight.

Kate Redmond, The BugLady 

Howdy, BugFans,

This Dogwood twig borer (Oberea tripunctata) missed the recent “Dining on Dogwood” episode simply because it wasn’t foraging among the dogwood’s white flowers; the BugLady found it in early July on a prairie plant (there was probably a red-osier dogwood nearby).

The Dogwood tree borer’s name is a study in confusion.  Despite its common name, its larvae have catholic tastes and are at home on a variety of woody plants including plum, viburnum, willow, mulberry, elm, laurel, dogwood, fruit trees, and blueberry and it’s also called the Elm twig girdler.  Although it received its scientific name (Oberea tripunctata) in 1787, that name was inadvertently given to a second beetle (the Raspberry cane girdler) in 1847, and the two beetles shared it until someone caught the mistake 30 years later (there’s also a Dogwood borer that’s a moth).  It is a Cerambycid (long-horned beetle) in the subfamily Lamiinae, the Flat-faced longhorns.

It’s a trim little beetle, a little less than a half inch long, and it can be found from the Atlantic through Kansas and the Dakotas.  In the East, it lives where Flowering dogwood grows, and although it’s not considered a serious pest, much of the on-line literature about it comes from Extension/Exterminators in the Southeastern states, where they take their Flowering dogwood seriously.

The Report of the State Entomologist on the Noxious and Beneficial Insects of the State of Illinois (1908) chronicles the “twig borer” part: “Among the insects whose nice and elaborate instincts connected with the placing of their eggs are the wonder of entomologists, we must class the twig girdlers, for their careful preliminary operations are such as to suggest a knowledge of vegetable physiology and the prevision of possible difficulties in the way of the development of their young certainly quite beyond the powers of insect intelligence, and an unsolved puzzle if regarded as a product of natural selection.  The twig-girdler of the dogwood is an example.  ……. prepares a chosen twig for the reception of the egg by first cutting a groove around it a few inches from its tip in such a way that the twig presently breaks off at this point, and afterwards making a second girdle, not so deep as the first, and from two or four inches farther back.  It then makes two parallel cuts, about a half an inch long, lengthwise through the bark between the two girdling incisions, and at the proximal end of these makes a short transverse slit in a way to form an angular flap, beneath which it pushes its egg.  The effect of all this surgery must be to stop the growth of that part of the branch operated on, and to check the flow of sap to the section where the egg is laid.  …..  The eggs hatch within a week or ten days, and the young larvae penetrate the twig, burrowing downwards toward its point of attachment, and making holes to the surface at intervals thru which to discharge their excrement.” 

Why the slicing and dicing?  The various cuts ensure that the larva will live in a sap-free zone, and another benefit is listed in an account of the Raspberry cane borer in the Forty-second Annual Report of the New York State Science Museum (1888), which says “It is supposed that the purpose served by the girdling is the arrest of the circulation of the cane in the portion thus treated, to the extent that the tender egg deposited therein may not be crushed by the vigorous and rapid growth of the tips at just this season.”

The result of all this slitting and chewing and boring can be defoliation, death of the tips of the shoots, girdled stems, wilting leaves, and separation of internal layers of the twig.  In smaller shrubs like blueberries, the larva may continue its journey down the stem into the root crown, killing the above-ground portion of the plant.

Adults feed on dogwood leaves (including those of red osier dogwood), making small holes along the leaf veins.  To see some beetle work, click on the pictures to magnify them http://www.barkbeetles.org/browse/subject.cfm?SUB=2346.

Not only do the legless larvae jettison their frass through holes in the bark as they tunnel, they get rid of the sawdust created by their excavations in the same way.  They overwinter as larvae within the twig, in tunnels that are plugged with frass at both ends, and when it’s time to pupate in spring, they do so in a chamber that is similarly sealed.  Depending on where they live, Dogwood twig borers’ life cycle may be a year (the South) or two years (Minnesota) or even three, mostly spent in the larval stage.

Despite being hidden in twigs, the larvae are found by woodpeckers and are parasitized by several wasps.  In one study, between 50% and 80% of larvae were parasitized.

Unrelated Insect Addenda:

• The BugLady saw her first wooly bear caterpillar the other day.  For more information on these beloved signs of fall, see: https://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/woolly-bears.cfm (ignore the part about Isabella tiger moths having two generations here in Wisconsin – the BugLady got that wrong; they only have one).
• BugFan Becca sent a video she made of some wooly beech aphids. Take a peek at the video in this Wikipedia entry, https://en.wikipedia.org/wiki/Beech_blight_aphid, then go outside and check a beech tree – ‘tis the season.
• In regards to last week’s Praying mantis story, Mississippi BugFan Joe says that “Part of the received wisdom concerning Devil’s Horses (aka mantises) in these parts when I was growing up was they will spit in your eyes and put them out, i.e. you go blind! I never met a victim of such an attack.”
• And another Praying mantis tidbit – BugFan Mary confesses that “Back in the 70’s when I knew nothing I picked a stick with an ootheca to put in a flower arrangement….and oh yes, I got those little guys hatching when it was too cold for them outside.”

Thanks, Becca and Joe and Mary.

Kate Redmond, The BugLady

Bug of the Week archives:

http://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/

Howdy, BugFans,

Every fall, the BugLady gets emails from people who are excited about finding their first Praying mantis, and who can blame them?  The large and charismatic Praying mantis is a rock star of the insect world.  What follows is a massively rewritten version of a BOTW from 2007.

A few summers ago, the BugLady got a phone call from a woman whose daughter was doing a project on Praying mantises.  She had phoned an “expert,” who told her that the PM is an invasive insect.  So, this BOTW starts with an aside:

Aside: There are a number of words that people use interchangeably to describe the status of certain plants and animals – alien, exotic, non-native, introduced, and invasive.  The first four mean (more-or-less) the same thing – that, whether accidentally or intentionally introduced, whether from another continent or another part of this continent, an organism is not from around here.  Apple trees, earthworms (here in God’s Country), Swamp darners, alfalfa, Asian ladybugs, chicory, honeybees, Helleborine orchids, rusty crayfish, Norway maples – not native to southeastern Wisconsin.  “Invasive” means that, native or not, an organism’s population grows large enough to have a negative impact on the community it occurs in.  Praying mantises in Wisconsin are introduced, etc., but they are not invasive. 

Most contemporary field guides put mantises in their own order, Mantodea, but older insect books group them with the grasshoppers (Orthoptera) (they’re not related to walking sticks, either), and newer books (cutting-edge science, here) will put the Mantises (despite their predatory adaptations) with termites and cockroaches in an order called Dictyoptera.  Bugguide.net notes that mantises “can reasonably be described as ‘predatory roaches.’”  The Greek word for them, “Mantis or Mantes,” is variously translated as “prophet,” “soothsayer,” and “diviner” (the Greeks believed mantises have supernatural powers).  Their common name causes confusion, but it’s PrAying mantis, because of their reverent posture, not PrEying mantis, for their eating habits.

The BugLady cannot speak to their religious proclivities, but they are superbly adapted as predators. The serrations/spines on the second and third sections of their abnormally long front legs interlock when they grab their prey, making escape impossible.  Their eyes are situated so as to afford them binocular vision; like hawks and owls they can see forward with both eyes and can judge the distance to their prey.  Like owls, they can rotate their heads significantly (but not like a corkscrew) (neither can owls), the only insects that are able to do so.

Mantises rely on camouflage and stealth to ambush their prey (there’s a pink Malaysian mantis that blends into tropical orchids, and there are some mantis species that chase their prey like tiger beetles do).  The BugLady found a mantis in New Jersey once that was blending into a pickerelweed.  She kept looking at the plant, thinking, “Wait – pickerel weed doesn’t have any parts where that plant has parts.”

According to Elizabeth Lawlor in the wonderful Discover Nature around the House, when an insect is beyond a mantis’s considerable reach, the mantis engages in a slow, swaying dance, making eye contact with its proposed meal, edging forward as it sways, until it is suddenly close enough.  It targets insects, spiders and other invertebrates, but tropical mantises have been observed holding hummingbirds, small snakes, bats, and baby mice.  Fellow mantises are fair game – hatchlings are advised to move away from the egg case hastily http://bugguide.net/node/view/73199.

PMs are visual hunters and therefore daytime feeders, but males may fly at night, tracking female pheromones.  A single ear, located on the thorax, helps them detect bats.

Females are famous for eating their mates in the heat of the moment, as we saw on that memorable “Buffy the Vampire Slayer” episode, but this behavior is reported much less often in the wild than it is in caged pairs, where the male can’t escape after mating.  After decapitation, the beat goes on, and she gets a protein boost.

She lays as many as 200 eggs in an egg case called an “ootheca” (today’s vocabulary word) that is at first foamy http://bugguide.net/node/view/1179075/bgimage, and then brittle, and that looks like dried shaving cream, and she dies soon afterward.  Check out Lawlor’s book for a description of the development and “birth” of the young mantises.  Cutest!  Nymphs!  Ever!  Cuter than Pandas!  http://bugguide.net/node/view/785153/bgimage,http://bugguide.net/node/view/784273/bgimage, http://bugguide.net/node/view/52496.  Newly hatched mini-mantises (which are so small that they can be dispersed by wind) shed about seven times on their way to maturity in late summer; only about 10% of the eggs in an egg case reach adulthood.

PMs may look you boldly in the eye and track your movements; they may straighten up, fan their wings out, and wave those extraordinary front legs at you; and they might even hiss and try to nip, but they are harmless to humans.

European mantises and Chinese mantises occur in Wisconsin.  Both have been for sale in the US since the late 1890’s (though one “outlier” source says that the European mantis came over on the boat in the 1600’s).  Both are “plus-sized” insects, measuring three inches (the European) to almost five inches (the Chinese) in length.  There are native mantises in the southern US, but conventional wisdom has it that Wisconsin’s winters are too cold for them.

The egg cases of European and Chinese mantises overwinter successfully here, and you can purchase them from garden stores/catalogs whether your climate supports them or not.  Long touted as the ultimate in biological control of garden pests, mantises are, alas, equal-opportunity predators, enjoying honeybees and butterflies as much as they do aphids and army worms.  Because they are intensely cannibalistic, they are “loners,” so your garden will never be humming with PMs.

The CHINESE MANTIS (Tenodera sinensis) may be tan or light green, often with a slim stripe along the top edge of the folded wing.  Initially introduced to Pennsylvania, possibly by accident in a shipment of nursery plants from Asia, it was soon released in other states.  According to bugguide.net, it may have contributed to a decline in populations of native mantises both by eating them and by out-competing them.

The EUROPEAN MANTIS (Mantis religiosa) also comes in pale green or tan, but it sports a black or a black-and-white bullseye at the base of each front leg.  Its distribution is wider than the Chinese; European mantises can be found across southern Canada but they don’t like the extremes of humidity.  They are the State Insect of Connecticut.

People often say to the BugLady “I love my mantis!  Can I keep it??  If I bring it inside and put it in an aquarium – will it live longer?”  (Great!  Sure.  No.)  Bringing them inside won’t prolong their lives by much – they’re programmed to die in fall.  Also, mantises have voracious appetites and hunt/eat all day (their development suffers if they don’t), so our “three squares a day” isn’t enough for them.  Pet mantises?  Yes – they make fascinating – if high maintenance and short-lived – pets, and they may become tame enough to sit on your hand.  Be forewarned!  If you bring a mantis ootheca into your nice, warm home in late winter or early spring, you’ll (very) soon find a few hundred teeny, ravenous, praying mantises crawling around (didn’t they make a movie about that?).

Fascinating Mantis fact – a mantis from Madagascar, Ilomantis ginsburgae was named for Ruth Bader Ginsburg.

And yes, Praying mantises are actually very small space aliens.

Kate Redmond, The BugLady

P.S. – the BugLady has heard all sorts of fall/winter weather predictions based on wooly bear caterpillars, the fur coats of squirrels, the depth of schooling fish, etc.  She is not sure what the scores of millipedes on her front porch are trying to tell her (“The time is short and the water rises”) (old book title).

Bug of the Week archives:
http://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/

Howdy, BugFans,

The BugLady has been seeing Viceroy butterflies recently – what a treat!  So, here’s an enhanced version of a BOTW that first appeared seven years ago.

Viceroy butterflies (Limenitis archippus) are found in the Family Nymphalidae, the Brushfoot butterflies.  This group is often called the “four-foot” butterflies because they carry their short front legs tucked up against their body and walk on the other four.  The Viceroy’s name comes from the fact that, while it is similar to the Monarch and the Queen butterflies, it is smaller, and by extension lower in rank in the British peerage.  Its genus name Limenitis comes from the Latin word for “marshes.”  Viceroys enjoy shrubby and open fields and wet meadows throughout the US (they’re less common in the Great Plains), north into Canada and south into central Mexico.

There are two or more generations of Viceroys per summer (depending on your/their latitude); first brood adults feed on sap flows on tree trunks, carrion, scat/droppings, and aphid honeydew, while those from later broods are more likely to chow down on nectar from a variety of flowers and on decaying fruit. They also take in minerals from the clay of roads.

Males bask on leaves, scanning their horizons for females, and they will chase intruding males for considerable distances up into the sky.

Female Viceroys lay just a few eggs per plant.  When the eggs hatch, the tiny caterpillars eat the shells of their eggs.  Newly-emerged stinkbug nymphs do this, too, thereby picking up bacteria – left on the shells by their mother – that will help them digest plant materials.  The BugLady found several explanations/guesses about Viceroy egg-eating behavior – to keep predators from spotting the egg/caterpillar; to harvest the protein in the egg; and to obtain nutrients that will be needed when the caterpillar matures and lays its own eggs.  Willow is the caterpillars’ preferred food, but they’ll also eat poplar and aspen and have been seen on members of the rose family.  Salicylic acid in the willow leaves is sequestered in the caterpillar’s body.

Viceroy caterpillars feed at night and hang out more-or-less in plain sight on leaf midribs during the day, and they’ve developed a curious behavior to confuse potential predators – they put together a “decoy bundle.”  Let Anna Botsford Comstock, naturalist extraordinaire, explain it in an 1898 article called “Insect Domestic Economy:” “the viceroy caterpillar is a night feeder and he uses the denuded leaf-stem for a perch during the day.  Stretched out lengthwise on this during the day, he is nearly invisible in his earlier stages.  Besides this he uses a very ingenious device to distract the attention of bright eyes from himself; he fastens with a silken thread, which he secretes from glands near his mouth, a bunch of debris [including leaf bits and frass, says another author] to the bare midrib just above the feeding place; as he gnaws off more of the leaf, he moves his little decoy bundle farther down the stem.  This is a clever performance, for if one of his foes should be hunting about this leaf and should start out on the denuded stem, it would meet with this empty and worthless mass to begin with and naturally be discouraged from farther [sic] investigation.”  Alternately, since some parasitoids locate caterpillars by following a trail of frass, another source speculates that a ball of frass hanging in plain sight may keep them discovering the caterpillar.

The early broods live out their life cycles in a few months, forming a chrysalis when it’s time to transform into an adult.  But the larvae of the final brood of summer do things a little differently – they overwinter as tiny caterpillars, wrapped in leaves of one of their food plants http://bugguide.net/node/view/182659/bgimage.  Donald W. Stokes, in A Guide to Observing Insect Lives, describes how the caterpillar shapes a leaf into its hibernaculum, according to pre-programmed specifications.  It eats the leaf from the tip down, sparing the midrib.  Then it rolls the remaining bit of leaf into a cylinder a half-inch long and an eighth-inch wide, securing it with silk.  It lines the inside of the leaf with silk, and, although the leaf is still attached to the shrub, it wraps silk around the leaf stem (petiole) and secures it with a band around the twig so the leaf will not fall in autumn.  When it crawls in, the final segment of its abdomen forms a living “operculum.”

The caterpillar that re-emerges in spring has catkins and new leaves to feed on; it finishes growing and forms a chrysalis in spring.  Viceroys are closely related to the Red-spotted Purple/White Admiral butterfly (Limenitis arthemis) (the Red-spotted purple and the White admiral species have been “lumped” and are sometimes called the “Red-spotted Admiral”).  Admiral caterpillars overwinter in the same fashion as the Viceroy’s, are also bird-poop mimics, and are so similar to Viceroy caterpillars that only their mamas can distinguish them for sure.

As Pyle points out in The Audubon Society Field Guide to North American Butterflies, Viceroys seek protection in each life stage by disguising themselves as something else.  Eggs resemble galls on willow leaves.  As the caterpillar molts and matures, it looks increasingly like a glob of bird poop (for another champion bird-poop mimic, Google the “Beautiful wood nymph moth.”  If you forget to add “moth,” the BugLady is not responsible for the sites you’ll get to).  A Viceroy chrysalis continues the bird-poop theme http://bugguide.net/node/view/114173/bgimage.  Adult Viceroys are famous for being mimics of Monarch butterflies, of previous BOTW fame.

There are lots of websites dedicated to telling the difference between a Monarch and a Viceroy.  Long story short, Viceroys (except a Mexican subspecies) have a “C-shaped” black line across their back wing that is visible from above or below.  Monarchs are larger, and they tend to flap and soar, holding their wings up in a loose “V,” while Viceroys fly with faster wingbeats, and when they soar, their wings are held more horizontally.

Ecologists have long preached that Viceroys have enjoyed a Batesian “Get-out-of-Jail-Free” card due to their resemblance to the toxic Monarch butterfly.  Monarchs are poisonous because their caterpillar host plant, milkweed, contains harmful cardiac glycosides (Batesian mimicry – the harmless imitating the harmful).  Recent research suggests that because willow leaves are very bitter, the Viceroy may be almost as distasteful as Monarchs.  In that case, Monarchs and Viceroys are mimicking each other, each cashing in on the other’s bad reputation (Mullerian mimicry).

As mimics go, the Viceroy is a flexible one.  Monarchs do not occur in the far southeastern or southwestern United States during the summer, so what’s a Viceroy to do?  No worries – it turns out that the Monarch’s close relative, the Queen butterfly http://bugguide.net/node/view/1149651 does, and a Florida and a Southwestern subspecies of Viceroys are Queen mimics http://bugguide.net/node/view/986323/bgimage.  The Viceroy is apparently more noxious than the Queen.

Kate Redmond, The BugLady

Bug of the Week archives:
http://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/

Howdy, BugFans,

Back in June, the BugLady stalked the inhabitants of a dogwood that sits by the edge of a wetland.  Some nice long-horned beetles – Strangaleptra abbreviate, Brachyleptura rubrica, Molorchus bimaculatus, and Clytus ruricola (no common names) enjoyed the flowers with her (as did a cast of thousands).  She’s seen these beetles eating pollen on several kinds of shrubs whose flowers grow in flattened, white clusters in late spring.

Long-horned beetles (family Cerambycidae) are a charismatic bunch with a lot of devotees.  Cerambycids can be remarkably long-lived – some exist as larvae for a decade and as adults for a few additional years.  While their elders feed on flowers, fungi, sap, and leaves (or not at all), the larvae of many species (beetle larvae are often called grubs) bore into dead and dying trees – they’re great for decomposition, because their tunnels are doorways for water, bacteria, and fungi, but bad for timber value if they inhabit not-quite and just-dead trees.  Adult cerambycids nip, some squeak (by rubbing their head against the “collar” of their thorax), many are good-sized, and some are spectacularly-patterned.  And then there are those horns (antennae)!  There are 1,000 or so North American species and a worldwide tally of 30,000.  All four of today’s beetles reside in the eastern half of the US.

STRANGALEPTA ABBREVIATA (“shortened stripe”) is a monotypic species – alone in its genus.  It’s one of the flower longhorns (subfamily Lepturinae), whose members can be dramatically wedge-shaped and who are often diurnal(active during the day).  Adult Strangalepta abbreviatas can be found in the understory of both conifer and deciduous woodlands, and their larvae are generalists, found in decaying hardwoods and conifers.  And that, other than its presence in biodiversity lists and photo sites, is the sum-total of what the BugLady could learn about Strangalepta abbreviata.

BRACHYLEPTURA RUBRICA (probably) (“brachy” refers to its slightly shortened elytra, or wing covers) is a flower longhorn of deciduous woods; its off-spring, which overwinter as larvae and pupate the next year, feed on decaying birch, maple, hickory, oak, cherry, and beech.  In his “Beetles in the Bush” blog, Ted McRae speculates that the stage of decay is more important to it than the tree species.  And that, other than its presence in biodiversity lists and photo sites, is pretty much all that the BugLady could learn about Strangalepta abbreviata.

MOLORCHUS BIMACULATUS has led the BugLady on a merry chase for several springs, now.  It’s a small and active feeder, never staying in focus for very long.  It looks like an ant mimic to the BugLady.  Not a flower longhorn,Molorchus is in the Cerambycinae subfamily; there are only three species in the genus, and all have greatly reduced elytra, and males have antennae that are longer than their body.  The larvae are found in a variety of hardwoods including maple, hackberry, and dogwood, and in grape vines.

Older books list three subspecies of Molorchus bimaculatus (“bimaculatus” means “two spots”) and say that each feeds on different plants.  Bugguide.net shows pictures of three forms – the mostly blackish M. b. bimalulatus, the red-thoraxed M. b. corni, and the brownish M. b. semiustus, but says that all three can be found on the same plants at the same time, and the subspecies thing needs to be reassessed.

CLYTUS RURICOLA is a beetle that hopes that you think it’s a wasp (that’s Batesian mimicry, when something that’s harmless imitates something that’s not).  The legless larvae of Clytus ruricola are found in very dead hardwoods, especially maple; adults eat pollen and like to hang out in woodland canopies.

The BugLady has mentioned before a blog called “The Backyard Arthropod Project” (“somethingscrawlinginmyhair”), by Tim Eisele, whose goal is “to document every arthropod that I can find on our property – about 9 acres on the north slope of Old Mill Hill in the Keeweenaw Peninsula of Upper Michigan.”  About this beetle Eisele says “Looking at the underside, we can see why it looks like a wasp when it flies: the abdomen is banded in yellow, just like a yellowjacket or most paper wasps.  It definitely has more of a beetle-like face.  It also “stridulates”: when I held it, I could feel it vibrating as it moved its head up and down in a nodding motion, and if I held it next to my ear I could hear a faint “eeeeee-eeeeee-eeeeee-eeeee” noise.”

The BugLady hereby declares Longhorn Appreciation Day.  Here’s some Cerambycid Eye candy: http://bugguide.net/node/view/217428/bgimage, http://bugguide.net/node/view/987104/bgimage, http://bugguide.net/node/view/230492/bgpage, http://bugguide.net/node/view/1095779/bgpage, http://bugguide.net/node/view/814705/bgpage, http://bugguide.net/node/view/734973/bgpage, http://bugguide.net/node/view/650114/bgimage.

Kate Redmond, The BugLady

The BugLady

Bug of the Week archives:
http://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/

Howdy, BugFans,

Wooly – one “l” or two, take your pick.

The BugLady keeps running into herself on-line as she does research, which is scary – makes her think that she ought to know what she’s talking about.  Lots of BOTW pictures are also floating around in Google Images, which results in a steady trickle of correspondence both national and international (the BugLady cheerfully told the folks at a Field Station in India that solving their problem of small aquatic worms and other invertebrates in their tap water was way beyond her pay grade).

When she got a query recently about the identity of a three-quarter-inch “worm” that had feathery tufts and hung out on the bottom sides of leaves, it didn’t ring any bells.  Wooly alder and wooly beech aphids cover themselves with waxy filaments, and so do the nymphs of some planthoppers (and she had photographed what she thought was a feathery planthopper on her own walnuts last year), but worms?  Anyway, two weeks later, she was staring at some of these mystery worms in person.

It was fun reading accounts in which other authors experienced similar confusion, several describing the joys of Googling “fuzzy white worm,” and other descriptors.  The BugLady, who is “key-word-challenged,” feels their pain.  Then she looked more closely at a larva and suspected that it might be a sawfly, and Google became more accommodating.  It’s a Butternut woolyworm (Eriocampa juglandis).  And yes – her “planthopper” was a BWW.

Sawflies – sometimes called “wood wasps,” a common name they share with a few other primitive wasps – are harmless members of the wasp order, Hymenoptera.  The females’ toothed ovipositor gives them their name.  Sawflies lack the “wasp waist” of other Hymenopterans, and although their larvae are often mistaken for caterpillars, the legs are different.  Sawfly larvae are fussy eaters, with many species tied to just a few host plants, and some larvae are considered pests.  One source said that many of the plants that sawflies prefer are chemically defended, which seems to bother the sawflies not at all.  Larval defense strategies include communal feeding (potential predators have trouble figuring out where one larva stops and the next one starts) and spitting vile liquids from their mouths.

When BWWs, which are in the Common sawfly family Tenthredinidae, are found south of the Mason-Dixon Line, it’s mainly in connection with black walnut trees, but the bulk of their range is the northeastern quadrant of North America – not coincidentally, the range of the butternut tree.

There’s some modern literature about BWWs, but, as always, the BugLady is charmed by the scientific writing of one-hundred-plus years ago.  Insects Injurious to Forest and Shade Trees (1881) describes them as “cylindrical, with eight pairs of soft, fleshy abdominal legs; the sections are transversely wrinkled pale, pea-green, with a powdery secretion low down on the sides, but above and on the back arise long flattened masses of flocculent matter (exactly resembling that produced by the wooly plant lice and other homopterous insects), forming an irregular dense cottony mass reaching to a height equaling two-thirds the length of the worm and concealing the head and tail.”  It goes on to say that the adults, at about ¼” long http://bugguide.net/node/view/754965/bgimage, are “seemingly small for so large larvae.”  It is believed that their disguise protects them from predators.

The BWW has a low-key presence in University/Cooperative Extension literature/Wanted Posters.  Its populations can vary drastically from year to year, and it appears in mid-summer (in the North) when its host is fully leafed out, which lessens its impact.  Trees survive with some temporary cosmetic damage, and control is generally not needed.  Females saw into the mid-rib of leaflets and deposit 20 to 30 eggs, one at a time, which eventually causes the leaflet to droop or fold and the midrib to turn pale; and while small larvae chew random holes in leaves, larger one may finish them off entirely, leaving bits of the larger veins behind.

Unadorned larvae http://bugguide.net/node/view/79473/bgimage hatch in about a week and commence producing waxy, white fronds to adorn themselves.  Each molt leaves the feathery skin behind http://bugguide.net/node/view/330789/bgimage, and the larva must cloak itself anew.  Finished growing, they drop to the soil.  The pre-pupal larva forms a cocoon in which it overwinters in a state of suspended animation (aestivation), pupating in spring.  The cycle is completed when adults emerge in early summer (here in God’s Country).

Enjoy BWW explorations (and pictures) by the folks at Hilton Pond at http://www.hiltonpond.org/thisweek030708.html.

Kate Redmond, The BugLady

Bug of the Week archives:
http://www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/