Wednesday, April 30, 2014

Fossorial Mason Wasps, genus Pterocheilus

Solitary mason wasps in the family Vespidae, subfamily Eumeninae, are surprisingly diverse in appearance and habits. Most species nest in pre-existing tubular cavities, or make free-standing mud nests, but not all. Some excavate burrows in the soil. Perhaps the most accomplished digging species are members of the genus Pterocheilus.

Female Pterocheilus, Malibu, California

I so rarely encounter this genus, let alone a female actively digging a burrow, that when I came across one at Charmlee Wilderness Park in Malibu, California on May 19, 2011, I at first identified it as a beewolf, then another type of “sand wasp” before finally realizing it was a eumenid. The longitudinal folds in her wings when she was at rest easily betrayed her true identity.

Wasps that dig burrows are called “fossorial” by entomologists. Most of those wasps are equipped with stout spines on the front feet. This attribute is called the “tarsal rake,” and it is highly effective in moving sand and soft soil at a high rate of speed. Some wasps, rather than kicking soil will instead “pull” it out of the burrow by carrying a pile in their front legs and under their “chins,” while backing out of the tunnel.

Female Pterocheilus are equipped with a “beard” of long setae on their palps, segmented mouthparts behind the mandibles, which also have a fringe of hairs.

© Sarah Landry, in Evans & Eberhard, 1970

This modification of their anatomy, called a “psammophore,” allows them to carry a load of soil away from their nest location and scatter it into the landscape. This behavior effectively eliminates all trace of their activity, making it nearly impossible for parasitic insects to find the burrow once the entrance is sealed.

Female carrying soil in her "beard"

Pterocheilus quinquefasciatus is a fairly large wasp, females ranging from 13-16 millimeters in body length. This is the species I have found here in Colorado Springs. It occurs west of the Mississippi River to the Rocky Mountains, north to the Northwest Territories. It is also found in eastern Oregon and Washington, and southeast British Columbia. It is apparently absent from Arizona, Nevada, and California.

According to Jelle Devalez, in posts of this species to his Flickr.com photo stream, female wasps lay a single egg in the bottom of their burrow before they go hunting for caterpillars. Jelle discovered the species nesting in Badlands National Park in South Dakota. Apparently, caterpillars of the Darker Spotted Straw Moth, Heliothis phloxiphaga, are the preferred prey at that location. The female wasp paralyzes a victim, then carries it in flight to the burrow. Up to five caterpillars may be stored in one cell.

Female P. quinquefasciatus

Most species of Pterocheilus are not as large, or so widely distributed geographically, so are easily overlooked. There are roughly forty species in North America, with most of the diversity in the southwest U.S. Little is known about the biology of most species. P. texanus makes a shallow, vertical burrow terminating in a single subterranean cell, as do most Pterocheilus. Anywhere from 3-9 caterpillars are stored in each burrow before it is sealed (O’Neill, 2001).

As always, I encourage my readers to document their own observations of solitary wasps through still images, digital video, and note-taking. The sky is the limit for the scientific contributions you can make.

P. quinquefasciatus female

Sources: Bohart, Richard M. 1996. “North American Pterocheilus III. Subgenus Megapterocheilus (Hymenoptera, Eumenidae),” Insecta Mundi 10(1-4): 217-224.
Bohart, R.M. 1940. “A Revision of the North American Species of Pterocheilus and Notes on Related Genera (Hymenoptera, Vespidae),” Ann. Entomol. Soc. Am. 33(1): 162-208.
Devalez, Jelle. 2011. “Pterocheilus (Megapterocheilus) quinquefasciatus,” Flickr.com
Evans, Howard E. 1977. “Notes on the Nesting Behavior and Immature Stages of Two Species of Pterocheilus (Hymenoptera: Eumenidae),” J. Kans. Entomol. Soc. 50(3): 329-334.
Evans, Howard E. and Mary Jane West Eberhard. 1970. The Wasps. Ann Arbor: The University of Michigan Press. 265 pp.
O’Neill, Kevin M. 2001. Solitary Wasps: Behavior and Natural History. Ithaca, NY: Comstock Publishing Associates (Cornell University Press). 406 pp.

Saturday, April 26, 2014

There's a Moth in my Salad!

Entomophagy is the term for the intentional consumption of insects as food; but you would be surprised by how many insects turn up in foods we eat regularly. Two recent incidents reminded me that it is remarkable we don’t find more recognizable insects in our food, and why it shouldn’t bother us anyway.

I was having lunch with my wife and various friends from church at a chain restaurant on Sunday, April 6, when one member of our party discovered an intact moth, yes moth, amongst her salad greens. We were both eating the same salad, so I was a little more careful with succeeding bites. I took home the specimen and discovered it to be a member of the Noctuidae or Erebidae family. This wasn’t surprising since the caterpillars of many owlet moths are notorious crop pests, several of which are known as “cutworms.”

Yep, that's a moth

The prevalence of insects or insect parts is so commonplace and unavoidable in the harvesting, processing, storage, and shipping of food products that the Food and Drug Administration publishes an entire handbook on the subject of Food Defect Action Levels. The allowable number of insect parts, or even whole insects (collectively referred to by the unsavory term of “insect filth”), varies markedly according to each food product.

On the other end of the spectrum, we have situations whereby perfectly innocuous vegetable matter is interpreted by a restaurant patron as an insect. I received a sample of material obtained from a meal at another chain eatery. Previous casual observations of the “specimens” by other parties concluded they were either insects or the parts of one insect. My own examination revealed no segmentation, no differentiation of body parts, and therefore no insect(s). The resemblance is, arguably, startling, kind of like camouflage or mimicry in reverse.

Nope, not bugs

The blackened, fibrous roots or stems masquerading as bugs were, of course, a cosmetic issue, just as an actual insect would be. With few, minor exceptions, insects in your meal pose no health threat whatsoever. We are simply accustomed to pristine produce, unblemished fruits and vegetables. Our crops are sprayed will all manner of insecticides, waxes, dyes, and other coatings to give us this standard. It is akin to airbrushing and “Photoshopping” images of models to present us with an unrealistic standard of human beauty.

I will still find it gross to come upon an insect in my salad, or a fly in my soup, but it won’t bother me beyond that. I was quite impressed with the nonchalant reaction of our friend, who simply removed the moth and went on eating….without calling a lawyer, even.

Thursday, April 24, 2014

More Beetles from Bones

Last week I wrote about a few beetle species that I recovered from nearly dry bones here in Colorado Springs. I now have an update, plus additional species found in carrion on a recent trip to a private ranch northeast of Pueblo. It is interesting to note the succession of carrion beetle fauna over time; and the differences in diversity depending on whether the carcass is a large mammal, small mammal, bird, herp (reptiles and amphibians), or fish.

I went back to the bones I found earlier, and discovered some changes as of April 18. I spotted another Northern Carrion Beetle, Thanatophilus lapponicus, before it quickly disappeared, and more dermestids that I previously identified as Dermestes marmoratus. However, a different, smaller species was now more abundant.

Hide and Tallow Beetle, Dermestes talpinus?

I have decided I cannot readily conclude what species are involved here. Twelve species of Dermestes are recorded from Colorado, many of which look nearly identical to each other. The smaller species present on the bones appears to be the Hide and Tallow Beetle, D. talpinus. It is covered in gold or coppery scales on the pronotum (top of thorax), and silvery scales on the elytra (wing covers).

I also found a single specimen of yet another species that is possibly the Fringed Dermestid, D. frischii.

Dermestes frischii?

My wife and I travelled to Chico Basin Ranch on Monday, April 21, mostly seeking spring migrants of the feathered variety. This is a sprawling, working ranch that straddles El Paso and Pueblo Counties, and is managed for both livestock and native wildlife.

Unfortunately, one of the first birds we came across was a deceased Bobwhite quail. Turning it over revealed a shocking diversity of beetle life.

Rove beetles in the family Staphylinidae are predatory, and the ones that visit carrion feed mostly on fly maggots. They are easily recognized by the shortened elytra (wing covers), and are perhaps reminiscent of earwigs.

Hairy Rove Beetle, Creophilus maxillosus

The Hairy Rove Beetle, Creophilus maxillosus, is enormous by staphylinid standards, measuring 11-23 millimeters. These insects fly well, but quickly dig themselves out of sight when uncovered.

Rove beetle, Philonthus politus

Another rove beetle species, Philonthus politus, was also present. It is much smaller, about 10 millimeters. Special thanks to Philip Howe and Max Barclay for suggesting the genus, and Adam Brunke for volunteering the species. Facebook interest groups are a wonderful thing.

Sexton beetle, Nicrophorus sp.

Two species of the family Silphidae were also under the bird carcass: Thanatophilus lapponicus again, and one of the sexton beetles, Nicrophorus sp. Sexton beetles, also known as burying beetles, are big (11-22 mm or so), stocky, and strong. They often work in pairs to dig under the corpse of a small animal, sinking it into the ground. They then chew the carcass into a literal “meatball,” and the female then deposits a small number of eggs in a crater atop the food ball. She’ll chew up small bits of meat and feed them to her larval offspring, cleaning the food of mold and other potential contaminants in her spare time.

Clown beetle, Saprinus lugens

Clown beetles in the family Histeridae are small, spherical, highly-polished insects that play dead or dig when disturbed. They are predatory on other small insects found in carrion, dung, and other unsavory mediums. This one is Saprinus lugens, a common and widespread species measuring 5-8 mm. Thanks to Alexey Tishechkin for the species identification.

Male Scooped Scarab, Onthophagus hecate

Many dung beetles will also visit carrion, such as the little “Scooped Scarab,” Onthophagus hecate. Males have a broad, forked horn projecting over their heads from the top of the thorax. They battle each other for the right to mate with a female. At only 6-9 millimeters, O. hecate is one of the smaller dung beetles.

Hide beetle, Trox sonorae

Last but not least, were cryptic “hide beetles,” Trox sonorae, in the family Trogidae. They are closely allied to scarab beetles. Trogids are rough in texture, and usually so caked in debris as to be nearly unrecognizable as insects. They also play dead so convincingly as to be easily dismissed as living creatures. They freeze in a random, rigid posture when disturbed. This species is only 8-11 millimeters in size, which only makes it even harder to spot. Trox consume dried skin, feathers, and other material when carcasses are in the last stages of decay.

Silphid carrion beetle larva
Dermestes larva

Later in the day, Heidi and I came across the remains of a large livestock mammal, and virtually none of the beetles found on the dead quail were on this much larger vertebrate. Instead, it was carrion beetle larvae, dermestid larvae and adults, and Red-legged Ham Beetles, Necrobia rufipes. There are three common species of Necrobia, all in the family Cleridae. While most clerids are predators, Necrobia adults and larvae actually do feed on carrion, cured meats, and other dried animal products. They can be pests in museums and taxidermy businesses. Ham beetles are about 4-7 mm., but are a lovely metallic blue. They glint in the sunlight as they run over the surface of a dried corpse.

Red-legged Ham Beetle, Necrobia rufipes

Forensic entomology is the study of insects that infest dead bodies. Blow flies (family Calliphoridae) play the most prominent role in crime scene investigations because they can help ascertain the time of death. The life cycle of flies progresses in a predictable fashion, faster at higher temperatures, slower at cooler temperatures. By collecting adults, larvae, and pupae, a criminalist can determine at what time a body was first visited by ovipositing female flies.

Obviously, other insects play a critical role in decomposition as well, and beetles are chief among them. Those of you with strong stomachs may want to examine animal carcasses you come across, as the insects found there can usually be found nowhere else. Just remember to pack the hand sanitizer.

Friday, April 18, 2014

Mourning Cloak

I have neglected butterflies on this blog for the most part, as there are plenty of other blogs about them, books and websites, too. Plus, let’s face it: they are easy to love. My general mission is to stir a passion for other insects and invertebrates. That said, at this time of year along the Front Range of Colorado, certain butterflies are the most obvious of insects. The Mourning Cloak, Nymphalis antiopa, is also admirable for its sheer durability.

This butterfly is one of the “tortoiseshell” butterflies, a subgroup of the family Nymphalidae, collectively known as “brushfoots.” Look at any nymphalid and it looks like the insect has only four legs instead of the customary six. The front legs are greatly reduced in size and drawn up close to the head, where they function more like extra mouthparts than legs. The female butterfly scratches leaves with those tiny legs, causing the plant to produce volatile compounds that the butterfly analyzes to make sure it is a proper host plant on which to lay her eggs.

Tortoiseshell butterflies overwinter as adult insects, crawling into crevices and cavities in logs, stumps, and other protected spots. A warm winter’s day will see them taking wing, before going back into hiding until early spring.

Once a Mourning Cloak emerges from hibernation, it seeks sustenance to fuel its flights. A favorite source of nourishment is sap oozing from wounded trees. Indeed, a sap flux can quickly become a mecca for these butterflies, as evidenced in the short video below. They are amazingly tolerant of each other’s company considering their usual behavior.

Male tortoiseshell butterflies are highly territorial, each one staking out a patch of real estate that it defends vigorously from other males, and even from other species. I say many a battle between a male Mourning Cloak and a male Hoary Comma on April 11, the day I shot most of these images along a riparian trail near the Bear Creek Nature Center in Colorado Springs. The insects would often literally bang into each other during their aerial dogfights.

While males quickly become tattered and exhausted, females, once mated, set about to find suitable host plants on which to lay eggs. You will find the Mourning Cloak to be most abundant in willow thickets, as Salix spp. are the favored hosts. Caterpillars will also feed on elm, birch, poplar, hackberry, rose, mulberry, and other trees and shrubs to a lesser degree.

Large masses of eggs, typically 100-200, are laid by the female, the ova encircling a branch or twig. The caterpillars pass through five instars (an instar is the interval between molts), eventually topping out at about 5 centimeters (two inches) in length. Black with white speckles and maroon spots, the larvae are studded with spikes.

They occur in large groups, so when you find one you will usually find several more nearby. During their younger instars they share a loose, tent-like web for protection from predators and parasites.

By June or July another generation of Mourning Cloaks is on the wing. There may be two generations in the southern reaches of this butterfly’s range, but at higher elevations and latitudes there is but one generation produced each year, fresh adults emerging in late August or early September.

The Mourning Cloak is holarctic, meaning it is found throughout the northern hemisphere. In Britain it is known as the “Camberwell Beauty.” Here in North America, it ranges from Alaska to Mexico, and the Pacific Coast to the Atlantic seaboard.

Few insects live as long as a Mourning Cloak in the adult stage. On average, they survive 10-11 months, though much of that is sequestered in a hibernaculum. They are always a welcome sight, and a true harbinger of spring if ever there was one.

Sources: Brock, Jim P. and Kenn Kaufman. 2003. Kaufman Field Guide to Butterflies of North America. Boston: Houghton Mifflin Co. 384 pp.
Ferris, Clifford D. and F. Martin Brown. 1980. Butterflies of the Rocky Mountain States. Norman: University of Oklahoma Press. 442 pp.
Pyle, Robert M. 2002. The Butterflies of Cascadia. Seattle: Seattle Audubon Society. 420 pp.

Friday, April 11, 2014

Beetles from Bones

This past Wednesday, April 9, I went exploring near my home to see what insects are out and about here in Colorado Springs this spring. In my wanderings I stumbled upon a few bones of some large mammal, providing an opportunity to find insects specific to carrion.

I am not terribly keen on handling carcasses, but these leg bones were mostly dry. The ligaments were still intact on one leg, but flies had long lost interest in these remains. Still, it takes little to attract ants, and some kinds of beetles. I managed to find three species large enough for photos, plus a couple very tiny rove beetles (family Staphylinidae) that quickly vanished when I turned over the bones.

The first insect I saw was, oddly, a Small Milkweed Bug, Lygaeus kalmia. Many normally herbivorous Hemiptera are opportunistic scavengers, though, so perhaps the appearance of this insect should not have been terribly surprising. The second insect was one I expected, and present in fair numbers considering the relative size of the carcass: Common Carrion Beetles, Dermestes marmoratus.

Dermestid beetle and Small Milkweed Bug

Dermestids are so efficient at scouring the last vestiges of flesh from bone that natural history museums employ colonies of the beetles to clean skeletons. This particular species, a relative of that indoor pantry pest the Larder Beetle, is a handsome insect measuring 10-13 millimeters. The silvery-gray scales on its otherwise black body make it look quite dapper considering the situations it frequents. D. marmoratus is found from southern California through the southwest, southern Rocky Mountains, and Great Plains states.

Dermestes marmoratus

The most spectacular specimen uncovered was a Northern Carrion Beetle, Thanatophilus lapponicus, also known as the Silky Carrion Beetle. It looks superficially like a giant dermestid, 8-15 millimeters in length, but it belongs to an entirely different family, the Silphidae. This species is holarctic, meaning it ranges across the entire northern hemisphere. In North America it is found in Alaska, Canada, and the northern tier of states in the U.S., plus the Pacific states to Baja, Mexico, and the Rocky Mountain states. The adult beetles have been found from March to October. Perhaps its hairy body helps to insulate it against cooler temperatures.

Thanatophilus lapponicus

The last beetle species I collected was a type of sap-feeding beetle in the family Nitidulidae. At only 3-5 millimeters, Nitidula ziczac is difficult to spot, let alone get a clear image of. Despite their name, sap-feeding beetles are highly diverse in their appetites. Some species are found in abundance inside yucca flowers, for example. N. ziczac is a well-known associate of carrion, found in North America mostly from the Great Plains westward, as near as I can tell from various references.

Nitidula ziczac

What truly amazes me about carrion-inhabiting insects is how they manage to locate such a scarce resource. They need the energy to fly to far-flung bodies, at just the right time. Certainly their olfactory powers are light years ahead of us humans (I detected absolutely no odor from these particular bones), and tuned specifically to aromatic compounds liberated during decomposition. However they do it, thank goodness they do, or we would be forever tripping over dead animals, before becoming deathly ill ourselves.

Source: Evans, Arthur V. and James N. Hogue. 2006. Field Guide to Beetles of California. Berkeley: University of California Press. 336 pp.

Tuesday, April 8, 2014

The Bagrada Bug

California and Arizona have an immigration problem. No, not those immigrants; I am referring to an insect known as the Bagrada Bug, Bagrada hilaris. This member of the stink bug family Pentatomidae is native to Africa but has found its way to the U.S. where it has quickly become a crop pest. It is also known as the "Painted Bug."

The Bagrada Bug has not been here long. It was first detected in June of 2008 in Los Angeles County, but is now found abundantly throughout southern California and adjacent southern Arizona, eastward through southern New Mexico and into Texas. It had previously established itself in Italy, Malta, and southern Asia.

This insect is frequently mistaken for the native “Harlequin Bug,” Murgantia histrionic, but the Bagrada Bug is about half the size of its native cousin, adults measuring a mere 5-7 millimeters.

Murgantia histrionica, the "Harlequin Bug"

The nymphs of B. hilaris are occasionally dismissed as beneficial lady beetles due to their bright red and black markings. There are five nymphal instars, an “instar” being the interval between molts.

Bagrada hilaris nymph

What makes the Bagrada Bug problematic is its appetite for plants in the cabbage and mustard family (Brassicaceae in today’s classification, Cruciferae of previous eras). So, kale, turnips, broccoli, radishes, and related vegetables are all on its menu. It doesn’t end there, either. The bug is also known to feed on potato, sorghum, cotton, papaya, maize, various legumes, and other crops. Ornamental plants like sweet alyssum and candytuft are also vulnerable.

The appearance of this pest in the U.S. caught everyone off guard, including entomologists. Its biology and natural enemies are barely known, so few control methods can be applied, let alone biocontrol agents like parasites and predators. We don’t even know exactly how fast the Bagrada Bug is spreading.

You can help improve our understanding of the distribution of B. hilaris by keeping an eye out for it and reporting your observations to your state department of agriculture. Having images to back up your identification can help immensely.

Almost all information on the Bagrada Bug in the U.S. is found online because the species is such a recent introduction here. The most trusted resources are websites with URL addresses ending in “.edu” or “.gov.” Commercial sources are often less accurate.

Sources: Arakelian, Gevork. 2013. “Bagrada Bug,” Center for Invasive Species Research, University of California, Riverside.
Flint, Mary Louise, et al. 2013. “Pest Alert! Bagrada Bug,” UC IPM Online, University of California.
Wisch, Hartmut, et al. 2012. “Species Bagrada hilaris - Bagrada Bug,” Bugguide.net.

Sunday, April 6, 2014

Sheetweb weaver, Drapetisca alteranda

I was fortunate enough to find many interesting insects and spiders while living in South Deerfield, Massachusetts in 2009. One nice surprise was stumbling upon a specimen of the sheetweb weaver Drapetisca alteranda. Not only is this spider quite small (females are only 4-4.5 millimeters in body length), but it is exceedingly well camouflaged. Oh, and nocturnal, too.

This spider is atypical of the family Linyphiidae and can be easily mistaken for something like a lynx spider or other hunting spider that does not spin a web, but waits in ambush instead. Drapetisca lives on tree trunks where it sits motionless. Close inspection reveals that it is actually not in contact with the surface of the tree, but sprawling across the thinnest of snares.

It was by sheer luck that I noticed the specimen imaged above. I was seeking insects and arachnids around a bright light outside the town library the night of July 30. The light illuminated not only the exterior of the library, but a nearby tree as well. Ants, beetles, and other insects paraded up and down the trunk, and I found at least one Common House Spider in her snare under a branch. My flashlight eventually revealed the Drapetisca at roughly shoulder height, much to my surprise and delight.

Male specimen, © Tom Murray via Bugguide.net

This spider is, unfortunately, best identified by characters that are not easily observed in the field. The jaws are armed with a set of three or four long spines that criss-cross (see image below). The female’s external genitalia (epigynum) are also diagnostic, but that necessitates turning the spider over and putting her under a microscope. Still, the overall appearance of the spider, and its posture on its web, help to eliminate other potential suspects.

© Charley Eiseman, "Bug Tracks" blog

As is the case with most organisms that are of no economic importance, precious little is known of this spider’s biology and distribution. It appears limited in its range to southern Canada and the extreme northern U.S. It is common in New England, and recorded from the Great Lakes region, Montana, Alberta, and British Columbia. It may be absent from the northern plains.

Female with egg sac, © Kyron Basu via Bugguide.net

Your own persistence and patience in seeking spiders like this one could reveal much new information. Nothing ventured, nothing gained, so do share your own images and observations.

Sources: Eiseman, Charley. 2011. “Kleptoparasite,” Bug Tracks blog.
Hollenbeck, Jeff. 2006. “Species Drapetisca alteranda,” Bugguide.net
Kaston, B.J. 1978. How to Know the Spiders (3rd Ed.). Dubuque, Iowa: Wm. C. Brown Company Publishers. 272 pp.

Friday, April 4, 2014

Cow Path Tiger Beetle

One of the few insects to have poked its head out while we still have the threat of snow here on the Front Range of Colorado is the Cow Path Tiger Beetle, Cicindela purpurea. Also known as the “Purple Tiger Beetle,” it seems to come in just about every color except purple. Whatever its wardrobe, it is a welcome sight and a challenging subject to stalk and photograph, whether here or elsewhere on the continent.

© Heidi Eaton

Tiger beetles in North America typically have one of two emergence patterns. Some have a two-generation spring/fall cycle whereby the adult beetles are present in those two seasons. Others have one generation seen only in summer. Many species also have specific habitat requirements, making them hard to find in the first place. Then there is the fact that if they aren’t moving, you have a hard time seeing them.

These beetles also earn their name: they are efficient predators of many other insects, even ants. They have reasonably keen vision and run swiftly, like diminutive cheetahs. They run so fast, in fact, that they can literally outrun their eyesight. When sprinting after a potential meal, they go blind, and must stop to re-focus. This run, stop, run behavior helps to identify them in the field. Get too close to one and it will fly, usually a short distance, land, and resume its darting gait.

Tiger beetle larvae are also predatory. Each lives in a (usually) vertical burrow just wide enough to accommodate the grub. A hump midway down its body, armed with hooks, anchors the larva against one wall. The overall appearance of the grub is an “S” shape. The flattened head of the larva is flush with the rim of its tunnel as it lies in wait for a hapless insect to blunder by. It then lunges with lightning speed, grabbing the victim in its jaws. When disturbed, a tiger beetle larva rapidly descends deep into its lair.

Adult Cow Path Tiger Beetles measure 12-16 millimeters and may be matte green, metallic green, bluish, black, or bronze-purple with green highlights. The species has been divided into named “races” based on these differences. Most have consistent ivory markings: a spot at the tip of each elytron (wing cover), and a mark that looks like an oblique tilde symbol (“~”). There may or may not be an additional spot near the edge of the elytron between the squiggle and the terminal spot.

It is not unusual to find two different color morphs to be mating, as shown here. They recognize each other by the dimples in the female’s thorax, which fit the teeth on the male’s jaws like a lock and key. Attempted mating by the male of another species would be futile, as his jaws would slip off her thorax.

Look for these lovely beetles in degraded prairie habitats, where there is sparse grass and plenty of bare patches of earth. They are not often found in large numbers, and while much of a given landscape may look to us to be hospitable to them, they can be sporadic at best.

The good news is that Cicindela purpurea is a very widespread species found over most of the northern three-fourths of the U.S., plus adjacent southern Canada. It is largely absent from the mid-Atlantic states, southeast, Texas, and coastal areas of the Pacific states. April, May, and September are the months this species is most abundant. Keep in mind that some years they might emerge earlier or later, depending on how mild the winter is.

Sources: Acorn, John. 2001. Tiger Beetles of Alberta: Killers on the Clay, Stalkers on the Sand. Edmonton: University of Alberta Press. 120 pp.
MacRae, Ted. 2011. “Monroe Canyon epilogue – Audubon’s tiger beetle,” Beetles in the Bush.
Anonymous. 2005. “Cow Path Tiger Beetle,” Tiger Beetles of Nebraska.

Tuesday, April 1, 2014

A Bed Bug Primer

”Sleep tight, don’t let the bed bugs bite.” That rhyme had no relevance for decades, but not any longer. After vanishing from the scene after World War II, bed bugs are back in our nightmares and, more importantly, our reality. Thankfully, bed bugs pose no threat from the transmission of blood-borne pathogens, but what they lack in virulence is more than made up for in litigations. Here is what you need to know about these insidious pests.

What is a Bed Bug?

Cimex lectularius is a member of the family Cimicidae in the order of true bugs (Hemiptera). Like all true bugs they have piercing-sucking mouthparts. Bed bugs use their beaks to drink the blood of human beings. Yes, we are the preferred host of this parasitic insect. Pets, other mammals, and birds suffice in a pinch for starving bed bugs, but people are the real target.

These are small, wingless insects, dorso-ventrally flattened (top to bottom) to the point of being paper thin. Adults measure only 4-6 millimeters, 7-8 millimeters immediately after feeding. First instar nymphs (those just emerged from the egg) are only one millimeter, and so pale as to be nearly invisible on the typical mattress or sheet.

First instar bed bug nymph
Life Cycle

Bed bugs go through five instars before becoming adults. An instar is the interval between molts. Each bed bug must have one blood meal in order to graduate from one instar to the next.

Bed bugs of various instars

Eggs usually hatch 6-10 days after being laid, though it can take up to 21 days. Each nymph stage lasts about one week under ideal conditions, longer if blood meals are irregular. Adult bed bugs typically live ten months to a year, feeding about every ten days. Since the average female can lay 500 eggs in her lifetime, you can imagine how quickly a population of bed bugs can build.

Second or third instar nymph
Do I Have Bed Bugs?

Obviously, inexplicable bite wounds can be a clue that you might have bed bugs. Bites are typically in a linear arrangement of three, evidenced as red, slightly-raised welts. However, some people do not react at all to bites, while others experience worse symptoms. If your bedmate complains, take them seriously.

A fair-sized population of bed bugs gives off a sweet, distinctive odor, so use your sense of smell. The French word for bed bug is punaise, a reference to this stinky aspect of bed bug biology.

If you suspect bed bugs, strip the bed and look for the insects and their signs, especially along mattress seams, under mattress buttons, the slots where the bed frame attaches to headboard and footboard, and other tight spaces. Bed bugs have to poop, and reddish or dark brownish stains are another sign of their presence.

Avoiding Bed Bugs

Inspect, inspect, inspect! You cannot be too careful in avoiding infestations. When traveling, inspect your lodging thoroughly, and elevate your luggage off the floor. Maybe put the suitcase in the bathtub. Look behind headboards that are flush against the wall. Take drawers out of the nightstand and examine them carefully. Look under carpet where it goes up the wall like a baseboard. Look in mattress seams and under mattress buttons.

Any place where there is serial occupancy is prone to infestations, from five star hotels to rental cabins, dorms, prisons, hospitals, movie theaters, planes, trains, buses, taxicabs….

Beware of secondhand furniture and avoid used mattresses. The rise in popularity of thrift stores is credited in part with expanding the bed bug empire, so again, inspect items thoroughly before purchasing.

Treating for Bed Bugs

Don’t panic, but do seek professional help. Bed bugs are extremely difficult to eradicate, so find a reputable, recommended company that has a successful track record. Understand that the extermination process is highly invasive. Furniture will have to be taken apart, perhaps even discarded. Your best bet may be heat treatment. Unfortunately, this is usually the most expensive option, but it is highly effective.

Complications may arise if you are in a multi-family dwelling, rental, or are the proprietor of a hotel, motel, campground, or other lodging enterprise. This is when legal representation is often sought to determine (or avoid) liability. Do make sure your interests are protected, but try to refrain from making any situation more adversarial than it already is.

Sources: Berenbaum, May R. 1989. Ninety-nine Gnats, Nits, and Nibblers. Urbana: University of Illinois Press. 263 pp.
Centers for Disease Control and Prevention. 2013. Parasites – Bed Bugs
Maestre, Ralph H. 2011. The Bed Bug Book. NY: Skyhorse Publishing. 181 pp.
National Institutes of Health. 2014. “Bedbugs,” Medline Plus.