Red-shouldered Bug

Today’s edition of “True Bug Tuesday” is all about the Red-shouldered Bug, Jadera haematoloma, family Rhopalidae. Last week, my wife and I happened upon a large number of this species in various life stages here in Colorado Springs. I went back a couple of times to get more and better images.

At first glance, it is easy to mistake Red-shouldered Bugs with boxelder bugs in the genus Boisea. Indeed, they both fall under the more general category of “soapberry bugs,” named for the affinity of these insects for the fruits of certain trees in the family Sapindaceae. Their appetite extends far beyond the berries and seeds of those and other trees and plants, though. They have been observed feeding on flower buds, oozing sap, and even dead insects.

Adults of Jadera haematoloma are overall slate gray with fewer red markings than boxelder bugs. They measure 9.5-13.5 millimeters in body length. Some specimens are brachypterous, meaning they have shorter wings than normal, revealing a bright red abdomen with a black bar or two on those exposed segments.

Nymphs lack wings, so the front half is gray while the back half is red. The nymphs can get very bloated while feeding, as demonstrated by the one imaged below. The nymphs pass through five instars (an instar is the interval between molts) before reaching adulthood. Freshly-molted adults are bright pink or orange.

There are usually at least two generations per year, more in the southernmost states. The bugs mate “tail-to-tail” and are thus easily distinguished from solitary individuals. Females unreceptive to mating signal that fact to approaching males by making noise. They stridulate by rapidly rubbing lateral edges of the abdomen against the adjoining thoracic segments.

A mated female digs a hole about one centimeter in depth in dry soil. There, guarded by the male, she lays a batch of up to twenty eggs. The ova hatch in about two weeks. One female, which usually mates multiple times with different males, can produce between 400 and 800 eggs in her adult lifetime.

Both nymphs and adults can overwinter in cracks, crevices, and other cozy niches. They occasionally take shelter inside homes and other buildings like boxelder bugs, rendering them a “nuisance pest” in some places.

The Red-shouldered bug is also known as the Goldenrain Tree Bug. It is native to the U.S. from Virginia south to Florida and west to Wisconsin, Kansas, Colorado, Arizona, and southern California. South of the border the species occurs from Mexico and the Caribbean to Colombia and Venezuela. It has also been accidentally exported overseas, at least to Asia.

This insect is easily confused with boxelder bugs, and any number of seed bugs in the family Lygaeidae which can be of similar size, coloration, and abundance. One must look at various subtle structural characters, rather than color and pattern, to distinguish them with any degree of certainty. With practice, however, one can render a confident ID in the field.

Sources: Carroll, Scott P. 2013. “Jadera haematoloma,” Soapberry Bugs of the World.”
Eaton, Eric R. and Kenn Kaufman. 2007. Kaufman Field Guide to Insects of North America. Boston: Houghton Mifflin Company. 392 pp.
Jing-Fu Tsai, et al. 2013. “The soapberry bug, Jadera haematoloma (Insecta, Hemiptera, Rhopalidae): First Asian record, with a review of bionomics,” Zookeys 297: 1-41.
Slater, J.A. and R.M. Baranowski. 1978. How to Know the True Bugs. Dubuque, Iowa: Wm. C. Brown Company Publishers. 256 pp.

Brown Recluse

The Brown Recluse, Loxosceles reclusa, is without question the most infamous spider in the United States. Frequently maligned as the cause of serious necrotic wounds, and often confused with many harmless species, its reputation is inflated far beyond reality.

Identification

Also known as the “fiddleback” and “violin spider,” Loxosceles reclusa is usually marked distinctively on the carapace. This dark, violin-shaped marking may be vague, or even absent; and many other spiders have similar contrasting patterns. The only way to positively distinguish Loxosceles species is by their eyes. Brown spiders have only six eyes, compared to the usual eight eyes most spiders have. This sextet of ocular organs is arranged in a triangular pattern of three pairs. Understandably, most people don’t want to get close enough to a spider to see its eyes, but that is what is necessary to confirm an identification. Many other spiders are similarly colored, and of similar size. Recluse spiders attain a body length of 5-13 millimeters, with a legspan up to 30-40 millimeters.

Geographic Range

The Brown Recluse is native only to the central and southeast U.S., from Texas to northern Georgia, southeast Nebraska, southwest Ohio, and states in between. There are twelve other species of Loxosceles in North America, two of which are accidental introductions from other parts of the world. The Chilean Recluse, L. laeta, is found in only a few old, historical buildings in greater Los Angeles. The Mediterranean Recluse, L. rufescens, has turned up in many large urban areas, but is again usually restricted to a few highly localized populations. The remaining ten Loxosceles species are confined to the southwest U.S., from south Texas to southeast California and southern Nevada, and are found outdoors more often than in dwellings and other structures. While it is possible for any of the brown spiders to be transported outside their normal geographic range via commerce or travel, the Brown Recluse is less likely to spread than the foreign species.

Bites

The medical significance of the Brown Recluse has been sensationalized by the media and the internet. Various websites display graphic images of the most extreme cases of envenomation, if the pictures even represent spider bites at all. Yes, the venom of Loxosceles is cytotoxic (destroys tissues), and can produce necrotic wounds in some bite victims. However, many other maladies can express similar symptoms. MRSA (Methicillin-resistant Staphylococcus aureus) is one of these. More to the point, spider bites in general are a rare phenomenon. They are simply overdiagnosed. You owe it to yourself to read this article by Dr. Richard Vetter, and insist that your physician rule out those other potential causes if you ever present what you believe is a “spider bite.”

Should you ever present with a suspected or confirmed spider bite, run, don’t walk, away from any physician who applies electric shock to “deactivate the enzymes in the venom.” This is not a practice endorsed by any respected body of doctors, yet I personally know one bite victim in a rural area who received such “treatment” back in the year 2000.

Precautions

It is relatively easy to avoid the prospect of a spider bite by taking simple precautions, such as those outlined in this article from Spiders.us. Simply never put your hands in places you can’t see. Do be careful moving items that have been stored for lengthy periods without disturbance, especially clothes and linens, as spiders frequently hide in garments and blankets. One of the specimens depicted here was in the folds of a blanket that was taken out of storage in a home in Leavenworth, Kansas.

Natural History

The Brown Recluse earns its name for its shy nature. They hide in narrow cracks and crevices, under stones or other objects, from which they spin a thin, haphazard, vaguely sheet-like web. Sometimes they wander out of their snares, especially at night. They are surprisingly tolerant of others of their kind, so large populations may occupy a small area. The family living in one home in Kansas City, Kansas collected 2,055 specimens in only six months. No one in the household was ever bitten, either. Individual recluse spiders in captivity live 2-3 years.

Conclusions

You should really not fear the Brown Recluse, but do give it respect. Exercise caution in places that you do not visit frequently, like the storage shed, cellar, deep recesses of the garage, and similar structures. Do not assume that every spider you see is a recluse. Male spiders of nearly all species, including those normally confined to webs, will wander in search of mates and may stray indoors in their quest for love. Should you really be concerned, take the specimen to an entomologist or arachnologist at a university, natural history museum, or even the public health department to have it properly identified.

Sources: Bradley, Richard A. 2013. Common Spiders of North America. Berkeley: University of California Press. 271 pp.
Forks, Thomas P. 2000. “Brown Recluse Spider Bites,” J. Am. Board Fam. Med. 13(6): 415-423.
Kaston, B.J. 1978. How to Know the Spiders (3rd edition). Dubuque, Iowa: Wm. C. Brown Company Publishers. 272 pp.
Vetter, Rick. 2004. “Causes of Necrotic Wounds other than Brown Recluse Spider Bites,” UCR Spiders Site. University of California-Riverside
Ubick, D., P. Paquin, P.E. Cushing, and V. Roth (eds.). 2005. Spiders of North America: an identification manual. American Arachnological Society. 377 pp.

No Answers

It dawns on me that I did not follow up on a previous post where I hinted that ”something really big” might be headed my way. Alas, it was not to be, and the decision has taken some of the air out of my hopes for the future.

Last spring, Answers.com approached me to ask if I would please apply to be their Insect Category Leader for their attempt to go head-to-head with About.com as a major source of online content. I complied by taking the editing test, submitting a sample blog post, and attaching my resumé. Then I waited. And waited.

I tried not to invest too many emotions and expectations in this opportunity, but it would have paid very well for an online enterprise, would have raised my public profile even higher, and most importantly let me reach a much broader audience with facts in the face of the proliferation of myths and urban legend that surround so many insects and arachnids. I truly see it as my mission to improve public understanding and appreciation of all misunderstood and feared animals, be they arthropods or vertebrates.

I periodically touched base with my contact person at Answers.com, and she was very gracious, honest, and punctual in her replies. I finally made one last contact on September 30 and received a reply the next day. The executives chose someone else to be the Insect Category Leader. I was devastated. I feel an obligation to provide at least a small amount of regular income to my marriage (one year and six months as of October 29), and I really thought this was my ticket.

I pressed for an explanation and was told that the only reason I was not selected is because I had done “work” for AllExperts.com, a subsidiary of About.com, which they see as their major competitor. Well, that “work” was all volunteer, to help build my credibility. Indeed, I was ranked as one of the top 50 experts, in all categories (remember doctors, lawyers, and others are on there, too), for 2009. The idea that a potential employer would use that against me, and assume that I would not resign from that “position” if I was hired left me outraged.

This is not the first time something like this has happened. I applied to be the paid expert for the “Pest Control” category at About.com years earlier, and their process is much more rigorous. I was new to writing for the internet, too. In the end, I was not selected for that position, either, due to philosophical differences as near as I could tell. After all, I make no secret of the fact that one of my major goals is to save people time and money by letting them know they rarely need professional extermination services, or over-the-counter chemical controls.

The only conclusion I am left with is that I am supposed to go out on my own. I am honored and grateful that the web wizard who brought you Spiders.us is willing to help me do just that. I have purchased the domain names “Eaton Insect Guides” and “Insect Field Guide,” and we are working methodically to get at least one of those sites erected. The remaining URL will likely funnel directly to the one we end up using.

The commercial site will be geared to addressing non-spider arthropods that I know people ask about consistently. I will need to solicit images of some of them. Eventually, there will be a forum component whereby users will be able to ask me, and the expanded community of people that results from having a forum, about insects and arachnids and other “bugs” they want to know more about.

Meanwhile, I will continue to post to this blog, at least sporadically, because my audience here seems more interested in learning about relatively obscure species that usually must be searched for. I appreciate your patience (and donations if you see fit) while I attempt to juggle both projects, plus Sense of Misplaced where I write about social and cultural issues and human nature. Thank you.

Woodlouse Hunter

This installment of “Spider Sunday” features yet another arachnid that causes undo consternation and fear among homeowners who encounter it inside their residences. The Woodlouse Hunter, Dysdera crocata, North America’s only representative of the family Dysderidae, is not dangerously venomous to the average, healthy human being or family pet.

That is not to say that this species doesn’t look formidable. It ranges from 9-15 millimeters in body length, and has very large chelicerae (jaws) with long fangs. The cephalothorax and legs are bright reddish brown or orange, and the abdomen beige or gray in color. These spiders have only six eyes instead of the usual eight that most spiders have, and they are arranged in a compact semi-circle at the front of the cephalothorax.

The Woodlouse Hunter is actually native to the western Europe, but has been introduced over much of the globe through commerce and other forms of human travel and enterprise. Here in North America it is most common in urban areas, favoring disturbed habitats in both forest and field.

Dysdera crocata is nocturnal, hiding by day under stones, logs, and boards or other debris. It ventures out at night in search of prey. The preferred prey is apparently terrestrial isopods known as woodlice, also called “sowbugs.” Sowbugs are also native to Europe, but now abundant in the U.S. and Canada. The spider uses its enlarged jaws and long fangs to pierce their armored prey, or turn it over and stab it in its soft underbelly. Captive Woodlouse Hunters will readily take other small animals as prey, so they are more plastic in their feeding habits than their name suggests.

Sowbug

The life cycle, revealed by captive rearing, is lengthy. It takes about eighteen months for an individual spider to reach maturity after hatching from the egg. A given specimen can then live an additional two to three years. Mating probably take place in the spring. Females contain a batch of up to seventy (70) ova within a rudimentary egg sac consisting of only a few strands of silk.

Look for the Woodlouse Hunter under objects outdoors. They may be hiding inside an oval, silken retreat, which they spin for purposes of molting and overwintering. Sometimes, the spiders stray indoors, and that is where they are most conspicuous. While there have been documented bites by this species, the symptoms amount to only localized pain lasting an hour or so, due mostly to the mechanical injury caused by those long fangs.

Dysdera is easily confused with Broad-faced Sac Spiders I the genus Trachelas, which have a nearly identical color pattern. Note that Trachelas has eight eyes, arranged in two rows across the wide front of the cephalothorax. Trachelas also lacks the long jaws and fangs of the Woodlouse Hunter.

Trachelas

I am keeping the specimen of Dysdera imaged here as a potential display animal I can take to public educational events. The more that can be done to alleviate our collective fear and loathing of spiders the better, and the Woodlouse Hunter can be a great ambassador for that mission.

Sources: Bradley, Richard A. 2013. Common Spiders of North America. Berkeley: University of California Press. 271 pp.
Jacobs, Steve. 2013. “Spider: the Woodlouse Hunter,” Fact Sheet. Penn State University Entomology Department.
Ubick, D., P. Paquin, P.E. Cushing, and V. Roth (eds). 2005. Spiders of North America: an identification manual. American Arachnological Society. 377 pp.