Ichneumon Wasp: Ceratogastra ornata

Welcome to "Wasp Wednesday." The wasp family Ichneumonidae is one of the most diverse in the order Hymenoptera, especially in the largely temperate climate of North America. Many species look superficially alike, even if they belong to different genera. One of the few species I can usually identify in the field is Ceratogastra ornata, which I still often mistake for a spider wasp anyway.

This wasp is well-named, for it is ornately patterned with yellow and reddish brown or black, depending on the geographic location where one finds them. In fact, four subspecies are recognized. Collectively, they are distributed from southern Ontario, Massachusetts, and southern Wisconsin west to eastern California and south to northern Florida, Louisiana, and Mexico.

Specimens from the northern reaches of the species’ range are generally darker, including the wings, with reduced yellow markings. Specimens from farther south and west, like the one shown here from Colorado Springs, are distinctly paler.

It has been suggested that this wasp is a mimic of stinging spider wasps in the genus Poecilopompilus. Indeed, the similarities in color and pattern are striking, though the spider wasps are slightly larger than the ichneumon's 10-12 millimeter body length in most cases. Here in Colorado Springs, I found another spider wasp, Ceropales, to be a potential model for the ichneumon.

Ceropales sp.

How do you tell the ichneumon wasp from the spider wasp it mimics? Look at the antennae for one clue. Ichneumon wasps have many, short antennal segments while spider wasps have far fewer, and longer, segments. Wing venation offers other characters, but one seldom gets a good look. Images of ichneumons may capture the “horse head” cell near the middle of the front wing, the horse’s “nose” pointed toward the wingtip.

Look for Ceratogastra ornata visiting flowers, especially composites. They are not only seeking nectar, but hosts for their larval offspring as well. You might see a wasp that appears to be stinging a flower bud, but this behavior is aimed at the eggs of a moth instead.

Details are sketchy, but apparently females of some moths in the genus Feltia (family Noctuidae, the owlet moths) lay their eggs in certain flowers. The caterpillars that hatch then migrate to the ground where they finish their life cycle as subterranean “cutworms.” The ichneumon wasp intercepts the egg stage, or newly-hatched caterpillar, injecting her own egg into the host. Her larva lives as an internal parasite of the caterpillar, likely letting it mature before feeding in earnest and ultimately dooming its host.

I have personally witnessed female Ceratogastra ornata ovipositing in buds of Common Ragweed, Ambrosia artemisiifolia. The entomologist J.C. Bridwell has also observed this, and found them ovipositing in Eupatorium thoroughworts as well. The wasps also visit goldenrod flowers, but are not known to oviposit among the blossoms (Carlson, 2009). The specimen shown here was favoring the extrafloral nectaries of Common Sunflower, Helianthus anuus.

The inability to identify ichneumon wasps to species should not be a barrier to observing them, or even collecting them. We know precious little about the biology and geographic range of the majority of species. Your images, posted to Bugguide.net, could shed light on this interesting group. Bob Carlson, a world authority on Ichneumonidae, often offers his expertise there as well.

Sources: Carlson, Robert W. 2009. “Database of Hymenoptera in America North of Mexico,” Discover Life
Eaton, Eric R., et al. 2011. “Species Ceratogastra ornata,” Bugguide.

Post 400

Dendroctonus sp., © Eric R. Eaton

I can hardly believe I have reached this milestone of a 400th post on this blog. When I started way back in February of 2009, I faced many unknowns. Would I have the discipline to write regularly? Would anyone read the posts? Back then, I knew nothing of social media, and hadn’t even started taking my own images.

There have been many life changes along the way, too. I became unemployed, employed irregularly and temporarily, and am now unemployed again. I met a wonderful woman, moved to her city, got married, and combined households. I have traveled fairly extensively, accruing images as I go.

My major goal in creating a blog was to help educate the general public about insects, arachnids, and other arthropods. I am still unsure if I am only “preaching to the choir,” but Facebook (and now Twitter) have helped extend the reach of this blog. As of yesterday, I was ranked number seven for invertebrate blogs on the Nature Blog Network (and #83 for all blog subjects).

What of the future of this blog? Expect it to continue. Do not expect me to move to WordPress. I find the interface to be horrible for me as a writer. I know this means you cannot easily view the blog on mobile devices; I know some complain that they cannot post comments. My apologies for that, but these are problems with Blogger, not me. Why they are not more responsive is beyond my comprehension.

You can expect more, and more frequent, content during the winter months when I am traveling less and spending less time in the field. You can always make requests for blog topics. I will gladly research and write about the subject you wish to know about, provided I have images, or you have some you can share to illustrate the topic.

“Spider Sunday,” “Moth Monday,” “True Bug Tuesday,” “Wasp Wednesday,” “OrThoptera Thursday,” and “Fly Day Friday” will continue to be irregular features, with a total of roughly two or three blog posts made each week. Whenever possible, I want to include images of the immature stages, especially for moths, but I have few identified caterpillar images of my own at present, perhaps even fewer that correspond to my images of moths.

So, this blog will continue, but is subject to change depending on what you, the audience, wants out of it. I welcome your suggestions, criticisms, and complaints, as always. Feel free to e-mail me if you cannot comment directly. Thank you. BugEric24ATyahooDOTcom.

Larder Beetle

Thanksgiving is an American holiday where we share a big meal with family and friends. Chances are, you might be sharing the leftovers with the Larder Beetle, Dermestes lardarius, as well.

Larder Beetles are members of the family Dermestidae, collectively known as skin beetles and carpet beetles. They feed as larvae and adults on all manner of dried animal products, the larger species enjoying cured meats, dry pet food, furs, taxidermy mounts, even cheeses. Their alias of “Bacon Beetle” gives a clue as to their food preferences. They can also be attracted to the carcasses of dead rodents between walls; or even accumulations of dead insects in light fixtures. I found this Larder Beetle larva crawling out from under our dog’s food bowl earlier this month, probably looking for a place to pupate.

Larvae of Dermestes lardarius average about 12-13 millimeters in length just prior to pupation. They are covered in long hairs like most dermestid larvae, but are distinguished by the pair of hook-like spines on the rear end.

Under optimal conditions, the life cycle from egg to adult can be completed in 40-50 days, but more commonly there is one generation per year. Eggs hatch in an average of less than twelve days after being laid in clutches of 6-8 by the female beetle in a food source. Larvae that eventually become adult male beetles undergo five molts, while female beetles pass through six molts in the larval stage. The insects may spend anywhere from 35-80 days as larvae, probably depending on how easy it is to secure enough food to complete the transition to adulthood. Larvae may wander in search of new food sources, too.

The pupa is enclosed in the last shed larval exoskeleton (“skin”). The larva bores into soft, but relatively solid material such as cork before pupating. The adult insect emerges in about fifteen days.

Adult Larder Beetles are 7-9 millimeters long, and blackish with a broad yellowish band across the elytra (wing covers) as shown. They can fly well. Note the relatively short, clubbed antennae that help distinguish them from other household insects and many other beetles. Adults can be long-lived, sometimes persisting for a year-and-a-half under ideal conditions. The species overwinters in the adult stage, too.

Prior to the age of refrigeration, the Larder Beetle and its cousins were serious competitors for stored food. Today, they are more of a nuisance pest. Prevention is the best way to control them. Store your vulnerable foodstuffs (including dry pet food) in durable plastic, glass, or metal containers with tight-fitting lids. Store furs, wool blankets and garments, and other fibers of animal origin in a cedar chest. Cedar has proven repellent qualities and is quite effective. Forget mothballs (utterly useless) and moth crystals (at least potentially carcinogenic).

I personally find these to be handsome beetles; and I admire their adaptability to exploit our own weaknesses in protecting resources we think are rightfully ours. In this season of giving, sometimes we give by accident. Happy holidays, everyone.

Sources: Bennett, Stuart M. 2003. “Dermestes lardarius (Bacon or Larder Beetle),” Stored Product Insects.
IPM.WG. 2012. ”Larder Beetle,” Museum Pests. Integrated Pest Management Working Group.
Klass, Carolyn. 2011. “Larder Beetle,” Horticulture Diagnostic Laboratory. Cornell University, Cooperative Extension of Suffolk County.

Spot-sided Coreid

Welcome to “True Bug Tuesday,” an irregularly scheduled celebration of the order Hemiptera. One of the bugs we found on our trip to south Texas earlier this month really stood out for its elegant color pattern. The Spot-sided Coreid, Hypselonotus punctiventris, was especially abundant at the Kenedy County Safety Rest Area on U.S. Highway 77, twenty miles south of Kingsville, Texas.

The rest area was landscaped with several trees and shrubs, including Yellow Trumpetbush, Tecoma stans. It was on this flowering legume that we found many specimens of the Spot-sided Coreid. It is found commonly in late October and early November in the vicinity of Austin, Texas on flowering Frostweed, Verbesina virginica.

This species apparently feeds on a variety of flowering plants as an adult. Actual known hosts upon which this insect feeds and grows include Rio Grande Abutilon (Abutilon hypoleucum), and other plants in the mallow family.

In the United States, the Spot-sided Coreid is known only from Arizona and Texas, though there is a recent record from Ashley County, Arkansas, as of April 20, 2008 (Choras III, et al., 2011). The species also occurs in Mexico, Belize, and Guatemala.

Adults average about 13 millimeters in body length, but their bold wardrobe makes them conspicuous. They can fly well, and when they open their wings they reveal a bright red patch on the dorsal (top) surface of the abdomen. Young nymphs have oversized, thickened antennae, and lack the wings adults have. I did find a final instar nymph (image below) at the Lennox Southmost Preserve, managed by The Nature Conservancy, at the very southern tip of Texas.

Despite its abundance, the Spot-sided Coreid is rarely, if ever a pest of agriculture or the garden. You are free to observe and admire this handsome insect with no fear it will doom your prize plants! Meanwhile, nearly any observations you make on H. punctiventris could represent new information on this non-pest bug.

Sources: Anonymous (“Larvalbug”). 2006. “Coreid bug (Hypselonotus punctiventris),” Hartman Prehistoric Garden.
Chordas III, S.W., R. Tumlison, H.W. Robison, and J. Kremers, 2011. “Twenty three True Bug State Records for Arkansas, With Two for Ohio, U.S.A.,” Journal of the Arkansas Academy of Science 65: 153-159.
Livermore, Laurence, Valérie Lemaître, W.R. Dolling, and M.D. Webb. 2013. Coreoidea Species File Online Version 5.0.
Valerie (aka “Larvalbug”). 2013. “Coreidae ~ Leaf-footed Bugs,” Austin Bug Collection.