How to Catch a Leafroller Caterpillar (Video)

Solitary wasps are amazing creatures, and their hunting behavior is particularly interesting. While my wife and I were in western Massachusetts last month, I was privileged to witness a female mason wasp, Ancistrocerus unifasciatus, successfully capture a leafroller caterpillar. I also got parts of the drama on video.

The scene: A large suburban residential backyard in Athol, Massachusetts, specifically planted to attract all manner of pollinating insects. Natural habitat is mixed hardwood and conifer forest, that abuts the property where this episode took place. Western Massachusetts is an odd mix of suburban and rural, actually, and it is difficult not to characterize this particular property as a "farm."

The leading actress: Ancistrocerus unifasciatus is a mid-sized mason wasp in the family Vespidae, subfamily Eumeninae. Females have a forewing length of 9.5-12 millimeters, males a forewing length of 6.5-9 mm. Both genders are basically deep brown or black with few yellow markings on the face, antennae, base of the abdomen, and legs. Males have a large yellow patch on the face, females a couple of spots.

Male, from Illinois. Note hooked antennae

Only females do hunting and nest building. The species ranges throughout the eastern U.S. west to Iowa, Kansas, and Texas. It also occurs in southern Ontario and Quebec, and Prince Edward Island.

The victim: I honestly cannot verify the identity of the caterpillar in this case, but it is certainly a leafroller in the moth family Tortricidae, and *possibly* the species Archips purpurana, which has goldenrod as a known host plant (among several others).

Is it coming out yet?

The wasp did not pursue its prey the way I thought she would. It even took me a minute to ascertain that she was hunting. I figured she would simply tear open the rolled leaf, grab the caterpillar, and go. Apparently the silk-bound fortress is more impregnable than I imagined.

Maybe at this end?

What the wasp did instead was pure genius. She took advantage of the caterpillar's instinct to "eject" when it feels like its home will be compromised. The wasp ran to one end of the leaf roll, then walked back, vibrating her abdomen to entice the moth larva to jetison itself. Back and forth she ran, as this video shows.

Unfortunately, I did not keep the camera running through the entirety of the hunt, partly due to fatigue, but when I saw the wasp suddenly had the caterpillar in her jaws, I resumed the video in time to see her fly to a nearby leaf to finish stinging her prey into paralysis.

Normally, the caterpillar, if threatened, takes a flying leap out of the leaf roll, trailing a silken line that it will then use to climb back once danger has passed. Kind of the caterpillar version of bungy jumping. The wasp obviously exploits this tendency, and very effectively.

Finishing off her victim with more stings

So, what does the wasp do with the caterpillar? Where does she take it? Adult wasps typically feed on flower nectar, aphid waste ("honeydew"), fermenting tree sap, and/or other liquids high in carbohydrates to fuel their energetic activities, like flying. So, this morsel of protein is not something the wasp would eat. The caterpillar is instead intended for her larval offspring.

And away she goes!

Ancistrocerus unifasciatus likes to set up house in abandoned mud dauber nests, especially those of Sceliphron caementarium and Trypoxylon politum. The mason wasp caches several paralyzed caterpillars in one of those cells. She lays an egg in the cell, then erects a partition and begins filling another cell along the length of the original, larger cell made by the mud dauber.

The larval wasp that hatches then has a larder of fresh food to feed it. Eventually it spins a silken cocoon, and pupates inside. An adult wasp emerges weeks later and chews through the mud wall to freedom.

Sources: Buck, M., Marshall, S.A. and Cheung D.K.B. 2008. "Identification Atlas of the Vespidae (Hymenoptera, Aculeata) of the northeastern Nearctic region," Canadian Journal of Arthropod Identification No. 5: 492 pp. (PDF version).
Krombein, Karl V., Paul D. Hurd, Jr., David R. Smith, and B.D. Burks. 1979. Catalog of Hymenoptera in America North of Mexico Vol. 2. Washington, DC: Smithsonian Institution Press. 2209 pp.

More Magic

One of the most magical things about the Magic Wings Butterfly Conservatory and Gardens in South Deerfield, Massachusetts is how so many butterflies can manage to virtually disappear before your eyes. You have to be very observant just to find some of these masters of “crypsis,” another word for camouflage.

Butterflies are generally pretty obvious and colorful when they are flying or feeding at flowers. Those at rest, wings closed over their backs, are often colored in earthtones of browns, grays, or greens on the underside, making them so inconspicuous as to be easily overlooked altogether. Even an entire cluster of individuals, like these common crows, Euploea core, dangling from a vine, can be easily dismissed as dead, drooping leaves. Native to India, crows are in the same family as our Monarch butterfly.

Some butterflies take hiding one step further by resting on the underside of leaves. This is also how butterflies shelter themselves from downpours and other inclement weather. Hanging beneath foliage in the butterfly house, this Malachite butterfly, Siproeta stelenes, easily avoided detection by visitors not accustomed to having to hunt for such beauties. The neotropical Malachite actually makes its way into the U.S., occurring in extreme southern Florida and Texas as well as Central America and northern South America.

The ultimate in true camouflage is demonstrated by yet another butterfly known as the Indian leaf, Kallima paralekta, one of several tropical Old World species known collectively as “leafwings” or “dead leaf butterflies.” Not only are the closed wings of the insect shaped like a leaf in profile, but the markings on the underside even include a “midrib,” vaguely visible on this tattered specimen.

Magic Wings also displays some other insects that defy efforts to describe the extent of their cryptic appearance. Enormous tropical walkingstick insects of several varieties are so nearly invisible as to cause one to question whether there is anything other than plants inside the cage. This close-up of one specimen confirms that this is indeed an animal rather than a vegetable, complete with a visible eye, antennae, and legs.

Walkingsticks still pale in comparison to their relatives the “walking leaf” insects of southeast Asia. Yes, the yellow object in this image is an insect, viewed from the side. These members of the genus Phyllium seem to literally be what they eat, as they are vegetarians that consume the pigments of their host plants. Not surprisingly, in the autumn when leaves are losing chlorophyll and more colorful pigments that are normally masked come to the fore, the insects get a dose of bright oranges, yellows, and reds. Voila! The insect’s built-in fashion sense doesn’t miss a beat.

Magic Wings

Saturday, November 7, dawned as a bright, sunny day, unseasonably mild for western Massachusetts. I decided it was high time I visited one of the major local attractions here, the Magic Wings Butterfly Conservatory & Gardens. The following day the facility was celebrating its tenth year anniversary, and it is no wonder they are still going strong.

Open year round from 9 AM until 6 PM, Magic Wings is well worth your time. Besides the free-flying butterflies in the tropical greenhouse there are also birds, reptiles, amphibians, and other insects on display both inside the greenhouse and in an exhibit area that serves as the anteroom before you enter. Everything is colorful, including this red-eyed tree frog from Latin America.

The butterflies really do steal the show, though, and I personally observed at least eighteen different species flitting around, feeding at flowers, perched on foliage, or courting each other in magical, amorous displays. This male birdwing butterfly, Ornithoptera priamus, native to Papua New Guinea, finally paused during his pursuit of the opposite sex.

Much smaller butterflies of the genus Heliconius were more camera-friendly, and no two specimens seemed to be alike, let alone the different species. This “cydno,” Heliconius cydno, seemingly a subdued, dull black in natural light, positively shimmered under a camera flash. Meanwhile, the “postman,” Heliconius melpomene, exhibits a mind-boggling diversity of color patterns such that they resemble different species. Only when courting does it become apparent that they belong together.

The morning light streaming through the glass roof definitely offers you the best opportunity to observe and photograph the butterflies, but hang around awhile longer. You can take your lunch break in the café, or go to the Monarch Restaurant next door, then return (showing the stamp on your hand) for an afternoon encore. At dusk, you will be treated to the crepuscular flights of the enormous “owl” butterflies, Caligo eurilochus. They will likely even alight on you while you are looking for other butterflies. What a way to end your day.

I’m not earning anything by endorsing this place, I just found it a pretty enchanting place to spend a day. Where else can you hear biker dudes and women and children all making exclamations of delight over insects? There is something to be said for any enterprise that can have such an effect on people, bringing out all our best qualities in a shared experience with nature, however artificial the environment.

Learn more about Magic Wings online at MagicWings.com.

Halloween Special: Ghosts and Pirates

What is more appropriate for Halloween than ghosts and pirates? We are not talking about trick-or-treat costumes, though, but spiders. Come to think of it, what is more appropriate for Halloween than spiders?! Just last week I found both kinds on an unseasonably warm night (October 21) here in South Deerfield, Massachusetts.

Both ghost spiders (family Anyphaenidae) and pirate spiders (family Mimetidae) prowl in search of prey. The similarity ends there, though, as they don’t resemble each other in the least, and their lifestyles are very different.

Ghost spiders are, not surprisingly, pale in color for the most part, and generally nocturnal in their habits, haunting foliage in pursuit of insects to eat. By day they hide in curled leaves that they tie together with silk.

Despite their name, ghost spiders are not very intimidating to humans. Adults reach a maximum of only a bit more than 8 millimeters. This one, a specimen of Hibana gracilis, was probably about six millimeters in body length. Big enough to take down the midge it is munching on, though. I think spiders recognize on some level the attractiveness of outdoor lighting to insects, as that is the situation I found this one in, and the pirate spider as well.

Pirate spiders are easily identified by their four eye patches and two wooden legs. But seriously, folks, the long spines on their legs help differentiate them from the cobweb spiders and sheet-web weavers that they otherwise might be mistaken for. The resemblance to other spiders is further complicated by the fact that you sometimes find pirate spiders in the snares of cobweb weavers. Their appearance there is as sinister as their name suggests.

Pirate spiders eat cobweb spiders, as well as orb weavers and other spiders. They dispatch the rightful owner of the web by biting the other spider on its legs, feeding from one after the other until the victim is totally drained. One reason for attacking the legs of its prey might be that the jaws of pirate spiders are fused at their base, not permitting the spider to open its mouthparts wide enough to bite other parts of its victims.

The specimen I found last week was Mimetus puritanus, the most common species in the eastern United States. There is a total of fourteen species in the genus in North America, however, and another ten that remain undescribed (awaiting the assignment of names by arachnologists).

BOO! Just making sure you are still paying attention. Ar-r-r-r-g, matey! Be on the lookout for ghosts and pirates in your own neighborhood.

The Art of Insect Tracking

Last Saturday night, October 3, I joined friends from Athol, Massachusetts to travel to the town of Cummington for the opening reception of an art exhibit by Charley Eiseman and Noah Charney. The two friends collaborate to teach tracking workshops and other field courses, but have also worked to produce the forthcoming book Tracks and Sign of Insects and Other Invertebrates, published by Stackpole Books with an expected release date of March, 2010. The exhibit, which runs through the end of October at the Cummington Community House, 33 Main Street, features stunning images taken for the book.

Noach Charney has become so enthralled with the intricate designs produced by insects in the course of their life cycles that he intends to produce his own coffee table book that celebrates these signs and patterns as literal art. Noah has a real eye for this and is painstaking in his commitment to producing high quality images. He is not above fooling his audience, either, posing optical illusions while rendering portraits of what insects leave behind. This image of leafcutter bee “damage” is perhaps the representative picture for the entire project. Can you tell what is going on here (hint: this is not a studio shot, and only minor manipulation of the leaves was involved)?

Charley Eiseman (right) met Noah (left) years ago when they helped found the “Woodsy Club,” as Charley’s mom affectionately calls it. Together with other like-minded souls, they practiced tracking, outdoor survival skills, and other activities. The two might call themselves “slackers” and poke fun at each other’s shortcomings, but there is nothing about them that is unprofessional when it comes to scientific endeavors. Keen eyes and endless curiosity have helped them spot the most cryptic of arthropod-created objects and solve enduring mysteries of “what did that?”

Anyone who hangs out with Noah and Charley will learn what true friendship means, and will laugh a lot along the way. You can’t help but come away with an appreciation of all things insect- and spider-created, or learn the art of observation and patience, either.

This blog entry is not just to promote their book and photography skills. You have to read the wonderful story in the Boston Globe for that. I just like these guys and the fine qualities they exemplify. Do take in the exhibit if you find yourself in the vicinity of Cummington, and by all means visit their website, the Northern Naturalists to keep track of their latest activities (no pun intended).

Triangle Spiders

An outing to the Westfield River in Hampshire County, Massachusetts last Sunday, September 6, included a stop at the Knightville Dam, where a unique arachnid awaited my discovery. There, among the goldenrods, asters, and ornamental black locust trees I found two triangle spiders, named for the shape of their web: a triangle that is essentially the sector of an orb web. The reduced size of the snare is just one puzzling feature of these amazing spiders.

Triangle spiders belong to the genus Hyptiotes in the obscure family Uloboridae. They are part of a larger group of arachnids called “cribellate spiders.” Cribellate spiders all share one feature in common: an extra spinning organ called a cribellum, located adjacent to the normal group of spinnerets. The cribellum issues a special type of silk that the spider literally “fluffs up” using a comb-like organ called a calamistrum, located on each hind leg.

Perhaps even more amazing than the “accessories” that uloborids have is what they lack. These are the only spiders in North America that do not have venom glands. That’s right, they are non-venomous spiders. So, you ask, how then do they subdue their prey? Great question for which I have not the foggiest answer. They probably do an extra-good job of wrapping their prey in silk, but not just any silk.

The cribellate silk threads in the part of the web designed to trap insects is not sticky like you would expect. Instead, it is tangled, and this is apparently just as effective as little droplets of glue.

Once it has erected its snare, the triangle spider sits on the thread near the tip of the twig or grass stem to which the apex of the triangle is secured. Depending on which book or article you believe, the spider either bridges a gap in this anchor thread, or simply perches there and reels in the slack line to render it taut. When a prey insect impacts the web, the spider then instantly releases the anchor thread, causing the web to rebound, further entangling the prey.

This feat of engineering and strength is performed by a very small animal. Even an adult female Hyptiotes is only 3-4 millimeters long. Males are 2-3 millimeters at maturity. Simply spotting one of these spiders is cause for self-congratulations for any naturalist.

There are four species of Hyptiotes (pronounced Hip-tee-OH-teez) in North America, three of which are chiefly western in their geographic distribution. The one shown in the image here is Hyptiotes cavatus, the sole eastern species.

Keep a sharp eye out for triangle spiders. The webs are mostly build about waist-high in weeds, on bridges and other structures, and twigs of trees and shrubs.

Panning for Bees

Yesterday (Saturday, August 8) I was invited to participate in a mini survey of local bees on the grounds of the Mount Grace Land Conservation Trust in Athol, Massachusetts. It was a unique event that revolved around the use of “pan traps” for bees and other insects that had been set out the day before.

We were fortunate to be under the guidance of Joan Milam, a largely self-taught bee expert from nearby Montague. She explained how pan traps are normally deployed. Pans (disposable plastic bowls were used in this case) of different colors are filled with water to which a single drop of detergent is added to break the surface tension. Bowls that are white, yellow, or blue seem to be most attractive to the wide variety of bees found here. They are often arranged in arrays, the distance between bowls carefully measured. Each separate trap can be addressed as its own sample, or the entire array can be the collective sample.

We collected the bowls, pouring the contents into a mason jar and then filtering the water and soap out with a piece of windowscreen fitted under the screw-on rim. Back inside the offices of the land trust we set about the task of rinsing and drying the catch. Turns out that bees and many other insects can take a surprising amount of abuse in the rinse and “tumble dry” cycles without undo damage. The biggest challenge is not melting the chitin in the exoskeleton.

Meanwhile, a few of us took our time in the field looking at what was currently on the goldenrod and other flowers, that might have escaped the pan traps. One such pollinator was this female leafcutter bee in the genus Megachile. Another was this flower longhorn beetle, Judolia cordifera, brought back to the makeshift lab where I took its picture before releasing it.

Several folks brought microscopes and we set about sorting the bees from look-alike wasps, flies, and other insects, then pinning them and further identifying them to family, genus, and species where possible.

This “crash course” in bee morphology was well worth it. We even got lunch provided, and took home a handy hand-out for our own use later. Special thanks to Sarah Mildren, Learning Services Coordinator, and Sean Pollock, Director of Finance and Operations, both of the Mount Grace Land Conservation Trust, who facilitated and hosted the event, and to Joan who was so patient with us novice bee people.

More Beetle Excitement

I got some exciting news this past week that I thought I would share. It involves a species of beetle that I collected while on a photo outing on the Fourth of July near the Quabbin Reservoir in Franklin County, Massachusetts.

While in a forest clearing (well, more of a slash pile of logging residue, actually), I saw a metallic woodboring beetle in the family Buprestidae. It seemed non-descript, much less brilliant in color than others I have seen, but I took its picture anyway. I wanted more images, though, so I captured it alive in a vial and took it home.

After chilling this highly active animal in the refrigerator, I placed it on the kitchen table and took more images. I was finally able to see that it was more or less metallic purple, the granular violet nature of its exoskeleton reflecting the light from my camera flash. It looked like the beetle had perhaps hatched out of a geode rather than a pine tree.

I posted my two images, one “in the wild” and the other “staged,” to Bugguide.net in the hopes of confirming my identification of it as Buprestis striata. Much to my surprise, the consensus among the experts is that this is actually a specimen of Buprestis sulcicollis, a much less commonly-encountered species. It was, in fact, previously unrecorded for the state of Massachusetts, though long suspected of occurring here.

Getting a state record is reasonably remarkable, but considering that I have been here in Massachusetts for a grand total of two months, it feels pretty spectacular. It would be great if it translated to a wage increase, but alas, I suspect all I will get out of it is “this stupid t-shirt” equivalent. As luck (good or bad depending on your viewpoint) would have it, the beetle subsequently died before I got around to releasing it. I will get to decide where the specimen will be deposited, which is a reward unto itself, I think.

The beetle deserves a bit of notoriety, too, but very little is known about Buprestis sulcicollis. Adult beetles measure from eleven to 15.5 mm. The recorded hosts for the larvae are pitch pine and eastern white pine. Its distribution is mostly from the Great Lakes to the Atlantic seaboard, but there are records as far west as Alberta and the Northwest Territories.

I encourage each of you to not assume that whatever creature you encounter is common, known from your area, or even already known to science. Take pictures, note the habitat, any behaviors you observe, and record the date and precise location you found the organism in. You never know what may become of your patient and careful study.

Firefly Tag

There is something about fireflies that is undeniably enchanting, and I looked forward to seeing them here in western Massachusetts. They occur in Arizona, too, albeit different species restricted mostly to riparian (streamside) habitats. Back on the evening of June 17, I looked for fireflies and other insects around the schoolyard here in South Deerfield. I was not disappointed.

The fireflies I came to know from my days in Cincinnati, Ohio, are largely crepuscular species, most active at dusk. Here, they appear to be active only after dark. Still, they ready themselves in the waning hours of daylight, appearing more out in the open on foliage along the edges of forests and fields.

The first firefly I encountered was a species of Photuris. It has been recently discovered that there are several cryptic species which can only be identified from subtle differences in their flash patterns. Morphologically, and apparently even genetically, they are otherwise identical.

Photuris gained infamy decades earlier when it was revealed that the females of one species, P. pennsylvanica, habitually mimic the flashes of female Photinus pyralis, thereby attracting the males of that other species. The male Photinus, no doubt optimistic at a positive response from a potential mate, alights to find the large female Photuris to be in the mood for something else. She devours him. Literally.

Dr. Thomas Eisner of Cornell University was the gentleman and scholar who not only discovered this behavior, but learned why it occurs. The father of chemical ecology, Dr. Eisner deduced that Photinus fireflies produce potent defensive chemicals called lucibufagins. That’s correct, the compounds are steroidal pyrones related to toad toxins. The Photuris fireflies, however, do not produce this chemical, instead acquiring it through the consumption of their cousins.

Ironically, the next firefly I found was a male Photinus. It is not pyralis, but a different species I have yet to identify. Just beginning to stir, he made a patient photographer’s model.

As darkness began to descend, along with hordes of hungry mosquitoes that made continued searching unpleasant, if not nearly intolerable, I managed to spy a female Photinus, perched on a grassblade. I would need my camera’s pop-up flash to illuminate her, but what I didn’t expect was her reaction to it.

After my flash would go off, which must have seemed like the sun exploding to the poor girl, she would twist her body and return the flash, though infinitely dimmer. Now it was obvious that she thought I was the male firefly of her dreams. Any male capable of producing that bright a light must be the most genetically fit of all her kind. I found it fascinating that she would purposefully direct her flash as well. There was no question where she was aiming it.

Try as I might, I could never catch her own signal. My flash simply failed to recharge in time to capture her faint greenish glow. It was a miracle I could even catch the literal tail-end of her contortionist performance with a subsequent shot.

I was recently asked if only the male fireflies fly and flash, and it appears to be true of at least a few species. It pays females to keep a low profile in grass or foliage, since they invest heavily in the production of offspring. Males are more “expendable” in the genetic sense, though anyone who has tried to catch flying fireflies knows just how futile an exercise it can be.

I enjoyed my game of “firefly tag” with the lovely female Photinus, but fearing she may not have enough battery life to reply to real males, I eventually let her be. Please share your own firefly encounters, and watch this space for future posts on fireflies, and the book about them that I have brewing….

For Whom the Bell Tolls

I have to relate a funny story. Lately I have been going out at night, looking for moths and other insects that fly to the meager outdoor lights here in South Deerfield, Massachusetts. Ok, I have two funny stories, now that I think about it.

The first night I went out looking, I stopped at two banks to prowl around their well-lit ATM and drive-through areas respectively. Naturally, I was stopped by the cops who had received reports of someone with a camera taking pictures of the banks. I eased their fears, and after a computer check I was on my way….Hey, can I help it if banks and the post office are the best-lit buildings in town? Geesh, you don’t have to make a federal case out of it. Well, come to think of it, I guess you do!

Last night I got a start of a different sort. Yet another nicely-lit building is our local library, located right next to a church complete with a bell tower. The library has a wonderful bright light, not one of those non-insect-attracting-good-for-nothing yellow sodium fixtures. Unfortunately, it is located about twenty feet up the side of the building. Thank goodness for the twenty power zoom on my Canon PowerShot SX10 IS.

I had found a neat moth to take an image of, which was apparently at precisely 11:30 PM because, just as I was about to press the shutter…DONG!!! Once my head quit rattling and my heart started again, I got the shot. I guess that will teach me to stay up so late on a work day.

Let Sleeping Wasps Lie

Awhile back I wrote an entry about the sleeping habits of solitary bees (“Let Sleeping Bees Lie”) that I observed and photographed in Tucson, Arizona. Here in western Massachusetts, I was fortunate enough to observe the sleeping habits of solitary wasps in the genus Ammophila, family Sphecidae. Known commonly as thread-waisted wasps, the females are energetic hunters of caterpillars, which they paralyze and store in a subterranean burrow as food for a single offspring.

There are many species of Ammophila found across most of North America, but they reach their greatest diversity in the arid west. More on that in a later post.

Get a grip!

How these wasps manage to get any sleep in this incredibly awkward position is beyond my comprehension. Maybe it is the wasp version of yoga, I don’t know. Simply gripping a twig with your jaws must be hard enough, let alone propping your body at an angle away from your perch. Though solitary, it is not at all uncommon to find loose aggregations of several thread-waisted wasps bedding down in a small area, like this. I once found a cluster of them at Smith Rock State Park in Oregon that was packed so densely that I initially mistook them for some strange flowering plant.

Like solitary bees, the wasps tend to turn in early, just around dusk. They can also appear to be in torpor (the scientific word for inactivity), but actually be quite alert and able to rapidly disengage from their perch. I approached another specimen on a later date, and it quickly regained “consciousness,” much to my chagrin.

There are sleeping bees here in Massachusetts, too, that adopt the same “look ma, no hands” biting grip as the cuckoo wasps in Tucson. This little bee is another parasitic type, in the genus Nomada, family Apidae. They are parasitic on other solitary bees, especially members of the genus Andrena.

Keep a careful eye out for these sleeping insects, especially in open areas with dry, twig-like vegetation, and around forest edges, even around your yard or garden. Solitary wasps and bees can be approached fearlessly, as they are not aggressive and females will not sting unless physically molested. The males possess no stingers. Well, all this talk about sleep has me yawning. I think I’ll turn in early. I also have a strange compulsion to bite the bedpost….

More moth fashions

While some moths came to the “Moth Ball” all gussied-up in their best black and white, or subtle and elegant pastels (please see the initial entry in my companion blog Sense of Misplaced), others sported complex patterns that rendered them virtual wall flowers, easily camouflaged on the bark of a tree, if not the wood siding on David Small’s shed.

Chief among these was this amazing tufted thyatrin, Pseudothyatira cymatophoroides, a member of the family Drepanidae that includes the hooktip moths and false owlet moths. It was one of the specimens to draw real oohs-and-ahs from the human spectators mingling among the winged wonders.

A wonderful salt-and-pepper pattern was displayed by this aptly-named “oak beauty,” Nacophora quernaria, one of the inchworm moths in the family Geometridae.

A chip off the old tree branch was what this “white-headed prominent” in the genus Symmerista resembled, its lovely white accent line adding to its disguise by imitating an exposed shard of underlying wood.

Perhaps the ultimate in obscurity was this slender little owlet moth in the subfamily Acontiinae that came incognito as, of all things, a bird dropping. Even more stunning, it is only one of over eighty species in that group, the majority of which are also bird-dropping mimics. Well, there is no accounting for taste, I suppose. More to come….

The "Moth Ball"

The evening of Saturday, June 13, 2009 I had the pleasure of attending a delightfully informal event christened the “Moth Ball” by host David Small and his wife, Shelley. The site of this outdoor gala was their home in Athol, Worcester County, Massachusetts. I was among several honored human guests, all anxious to meet the nocturnal Lepidoptera that we hoped would be dancing under the blacklights.

Unfortunately, the weather was patently awful, raining incessantly all night long and into the following morning. No worries, though, as many moths, and other intriguing insects, showed up anyway, and all the people found plenty of entertainment indoors getting to know one another, perusing David’s library, looking at online moth websites and photo galleries, drinking, eating, and occasionally braving the elements to see new arrivals at the lights.

David has a great sense of humor, is laid back, and was always looking to make his guests comfortable. Shelley must have stocked the place with every beverage known to man, and then made strawberry shortcake. We were all well fed and watered. David and most of the guests are “amateur” naturalists, each with their own specialty and command of that group of organisms. Most of them knew far more about moth identification than myself, and I learned a great deal.

Some folks stayed overnight and were treated to comfortable sleeping accommodations and a fantastic breakfast the next morning. Many of the moths apparently liked the place well enough to hang around themselves, or else they had hangovers and were sleeping it off.

Someone made a rough tally of the lepidopterans seen over the prior evening and that morning and it totaled over sixty species, bad weather and all.

For a peek at the more interesting moths snapped by the paparazzi, please visit my companion blog, Sense of Misplaced, and keep an eye out here for additional items related to the Moth Ball. Better yet, hold your own event. It is a sure cure for the summer doldrums.

Giant ichneumon wasps

Prowling around a pile of cut logs near my temporary residence in South Deerfield, Massachusetts on the evening of June second, I almost literally stumbled upon one of the most spectacular wasps on the continent. Female giant ichneumon wasps in the genus Megarhyssa may look menacing, wielding a whip-like “tail” that can exceed their own body length, but they cannot sting and in fact are quite shy, easily startled by sudden movements. It is a pity that people are often so alarmed by these insects, as they have an extraordinary life cycle.

That long, streaming appendage at the end of her abdomen is not a stinger, as the uninitiated tend to assume, but an egg-laying organ called an ovipositor. What she does with it is truly remarkable. She is seeking the grubs of another stingless wasp, the “pigeon horntail,” Tremex columba. Horntail grubs bore in the solid wood of dead, dying, or severely-weakened trees. Along comes a giant ichneumon wasp. The ichneumon somehow “divines” the location of the horntail grub inside the tree or log, then arches her back to pull her ovipositor into position to drill into the wood to reach the horntail grub. Whether she actually penetrates the solid wood, or winds her thread-like organ through existing cracks and crevices is still a mystery, but she manages to deliver her nearly fluid egg to its target host. The ovipositor is actually three filaments: two form a sheath for the actual ovipositor, bracing the animal’s abdomen and allowing the ovipositor to work smoothly without undo bowing.

Once her mission is accomplished, and her egg is attached to the horntail grub, the adult female ichneumon slowly withdraws her ovipositor and begins the process over again, walking the log or tree with antennae outstretched like divining rods.

Meanwhile, her egg eventually hatches, and the larval ichneumon attaches to the exterior of the horntail grub. It will wait patiently for its host to reach a large, nearly mature size, then begin consuming it. The horntail grub is doomed, destined to yield an adult ichneumon rather than a horntail wasp.

Look for giant ichneumons around dead or dying trees at all times of the day. While ovipositing, females are vulnerable, and one can sometimes see where a wasp was taken by a predator. A hair-like filament protruding from a log is all that is left of the wasp in such cases.

Male giant ichneumons like this one can also indicate the presence of females as they vie for mating opportunities. Note that they almost resemble a different species of wasp! Many males may gather at the site where a female is about to emerge. It is quite a spectacle.

Four species of giant ichneumons collectively occur over most of North America. The ones shown here are probably the species Megarhyssa macrurus. Females can vary considerably in size depending on the size of their host as larval wasps. Smaller individuals tend to have reduced spotting on the wings (or no spots at all). Enjoy looking for these insects and observing their amazing behavior.

Housemates

Besides the human and canine residents at 24 Sugarloaf Street, our house is also occupied by a variety of arthropods, mostly spiders. Crystalyn says she is not fond of spiders, so I’m hoping she doesn’t read my blog, at least for the sake of the health of these arachnids living with us.

The first spider to meet my acquaintance was this very gravid (egg-laden) female “prowling spider” of the family Miturgidae, on the ceiling of the bathroom. She is most likely a member of the genus Cheiracanthium, known also as “longlegged sac spiders.” The genus used to be in the family Clubionidae, but was moved to the Miturgidae in 1997, a decision still being debated in arachnological circles.

These spiders are mostly nocturnal, prowling during the night then spinning silken retreats in which they spend the day. This girl spun a bivouac as I watched.

Later I would find her mate in the kitchen. Well, it was an adult male at least, evidenced by the modified palps. They appear as the dark “boxing gloves” near his mouth. The palps (or pedipalps) are leg-like mouthparts that double in the male as intromittent sex organs. He deposits sperm on a mat of webbing, then draws it into each palp. These are complex appendages, designed to fit like a key in a lock, the lock in this case being the female’s sex organ called the epigynium. Like the female, the male also “sacks out” during the day.

Cheiracanthium had long been considered a genus of spiders at least mildly venomous to humans, but research has proven that this is a myth. So, I let them roam and carry out pest control activities. We definitely have too many mosquitoes here!

Crane flies of the family Tipulidae are very abundant now, some species being attracted to lights at night, and inevitably one strays indoors. This one has patterned wings. It is on the bathroom ceiling, too, but I don’t know whether one of the spiders got it. Crane flies are often mistaken for giant mosquitoes, or are referred to as “mosquito hawks,” but the adult insects probably do not feed, let alone take prey. Their size is deceptive as they are fragile insects. Look at one cockeyed and a leg will fall off. Their lifespan as winged insects is brief, just long enough to find a mate and reproduce. Crane fly larvae live in an incredibly variety of habitats, with diets that vary with the genus to which they belong.

A more permanent guest is yet another spider. This is what I imagine is a juvenile long-bodied cellar spider, Pholcus phalangioides, because adults are much larger. This one is well on its way, though, especially if it continues catching prey in the bathroom doorjamb like this. Cellar spiders are totally harmless to people and pets. While they do build tangled webs, they will also stray from those webs into the webs of other spiders and kill and devour them. Pholcids are frequently referred to as “daddy longlegs,” but that colloquial name is also given to harvestmen, arachnids of the order Opiliones (not spiders), and, ironically, to crane flies, especially in England. A crane fly would be more than this little one could handle.

Crystalyn is so busy that she sometimes forgets to turn the oven off, let alone observe the room for roaming arachnids. Her dog Ruby did see one, once, in the dining room, and drew our collective attention to it as it crossed the ceiling out of reach.