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.

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.

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.

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 nymphLife 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 nymphDo 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.