Missouri

T.G.I.Flyday – Chalcosyrphus?

/ Ted C. MacRae / 5 Comments

When I was an entomology student, I learned that flies in the family Syrphidae are called “hover flies,” due to their habit of hovering in front of flowers, and that the larvae are predators of aphids. As is the case for nearly every other group of insects, I now know that there are exceptions–often many—to the typical rule, and the fly shown in the above photograph is a perfect example of such. Being a beetle-man (and a wood-boring beetle-man, at that), I don’t generally notice flies unless there is something unusual about them. This fly was seen last summer at Sam A. Baker State Park in southeastern Missouri on the trunk of a very large, recently wind-thrown mockernut hickory (Carya alba) tree. I had never seen a fly quite like this before, but everything about it suggested an intimate association with dead wood, including its relatively large, hulking, black form and the way it repeated returned to and landed on the trunk of the dead tree each time I disturbed it. It instantly made me think of robber flies in the subfamily Laphriinae, which includes Andrenosoma fulvicaudum and many species of Laphria that, as larvae, tunnel through dead and decaying wood where they prey upon the larvae of wood-boring beetles. While it was quite obvious that the fly in the photo was not a robber fly, imagine my surprise when I eventually determined it to be a member of the family Syrphidae. For now I’ve provisionally settled on the genus Chalcosyrphus, although it lacks the steely blue cast exhibited by the only all-black species of the genus—C. chalybeus—shown on BugGuide. Another species, C. piger, looks very similar but seems always to have some red on the abdomen, which this individual definitely lacks. Perhaps the related genus Xylota is also a possibility, although the “gestalt” does not seem to quite match that of any shown on BugGuide. Most interesting for me are the distinctly enlarged and toothed metafemora, which along with the correspondingly curved tibiae suggest some predatory function, but the literature that I have seen makes no mention of such, but rather that the adults feed on pollen. My hunch about its association with dead wood does seem to be true, although it now seems the larvae are saprophages rather than predators within the wood, as I first imagined.

Copyright © Ted C. MacRae 2012

Beetle botanists

/ Ted C. MacRae / 16 Comments

Calligrapha spiraeae on Physocarpus opulifolius | Jefferson Co., Missouri

While Dicerca pugionata (family Buprestidae) is, for me, the most exciting beetle species that I’ve found in Missouri associated with ninebark (Physocarpus opulifolius). it is not the only one. The beetles in these photographs represent Calligrapha spiraeae, the ninebark leaf beetle (family Chrysomelidae). Unlike D. pugionata, however, I almost never fail to find C. spiraeae on ninebark, no matter when or where I look, and whereas D. pugionata has been recorded in the literature associated with a few other host plants like alder (Alnus spp.) and witch-hazel (Hamamelis virginiana), C. spiraeae is not known to utilize any other plant besides ninebark as its host.

Beetles in the genus Calligrapha are among the most host-specific of all phytophagous beetles, with most of the 38 species in this largely northeastern North American genus relying upon a single plant genus as hosts (Gómez-Zurita 2005). The genus as a whole is fairly recognizable by its dome-like shape and black and white or red coloration, with the black markings on the elytra varying from coalesced to completely broken into small spots. The species, however, are another matter, with several groups of species that are quite difficult to distinguish morphologically. Fortunately most of them can be easily distinguished by their host plant (although such information is rarely recorded on labels attached to museum specimens). Calligrapha spiraeae, for example, with its reddish coloration and small black spots, looks very much like two other species in the genus—C. rhoda and C. rowena. Those latter species, however, are restricted to hazel (Corylus spp.) and dogwood (Cornus spp.); as long as the host is known, the species can be readily identified in the field.

At this point you may be wondering why the species name refers to the plant genus Spiraea rather than Physocarpus. In fact, ninebark was already known as the host plant when Say (1826) described the species, but the name spiraeae was given because at the time ninebark was included in the genus Spiraea (Wheeler & Hoebeke 1979).

REFERENCE:

Gómez-Zurita, J. 2005. New distribution records and biogeography of Calligrapha species (leaf beetles), in North America (Coleoptera: Chrysomelidae, Chrysomelinae). Canadian Field-Naturalist 119(1): 88–100.

Say, T. 1826. Descriptions of new species of coleopterous insects of North America. Journal of the Academy of Natural Sciences of Philadelphia 5:293–304.

Wheeler, A. G., & E. R. Hoebeke. 1979. Biology and seasonal history of Calligrapha spiraeae (Say) (Coleoptera: Chrysomelidae), with descriptions of the immature stages. The Coleopterists Bulletin 33:257–267. 

Copyright © Ted C. MacRae 2012

Dicerca pugionata – safe and sound!

/ Ted C. MacRae / 22 Comments

Dicerca pugionata on Physocarpus opulifolius (ninebark) | Jefferson Co., Missouri

One of my favorite beetle species in Missouri is Dicerca pugionata—a strikingly beautiful jewel beetle (family Buprestidae) found sporadically across the eastern U.S. Unlike most species in the genus, which breed in dead wood of various species of trees, D. pugionata larvae mine living stems of certain woody shrubs—namely alder (Alnus spp.), witch-hazel (Hamamelis virginiana) and ninebark (Physocarpus opulifolius) (Nelson 1975). When I first began studying Missouri Buprestidae (way back in 1982), the species had just been reported from the state based on a single specimen (Nelson et al. 1982). I happened to stumble upon these beetles at what became my favorite collecting spot during the 1980s—Victoria Glades Natural Area, just south of St. Louis in Jefferson Co. For several years while I was visiting Victoria Glades, I found these beetles regularly during spring and fall on stems and branches of living ninebark plants growing within the ravines and along the toeslopes at the lower edges of the glades.

After finding the beetles at Victoria Glades (and nearby Valley View Glades Natural Area), I made it a habit to examine ninebark wherever I found it growing in Missouri. Ninebark is actually rather common in the state along the rocky streams and rivers that dissect the Ozark Highlands. Interestingly, I almost never encountered this beetle on ninebark elsewhere in the state. I’m sure it occurs in other areas, but probably at too low a level to be easily detected. I surmised that the populations at Victoria and Valley View Glades were unusually high due to the non-optimal conditions for its host plant. The ravines and toeslopes where the plants grow are drier than typical for ninebark, and unlike the lush, robust plants found in moister streamside habitats, the plants at these glades are small, scraggly and often exhibit a certain amount of dieback. It seemed likely to me that the plants growing in the glades were less capable of fending off attacks by these insects, thus resulting in relatively higher numbers of beetles at these glades.

After the publication of my “Buprestidae of Missouri” (MacRae 1991), it would be many years before I actually returned to Victoria Glades. When I did return, I was pleased to see that management practices (e.g. prescribed burning, cedar removal, etc.) intended to halt the encroachment of woody vegetation and preserve the glade’s pre-settlement character had been implemented in the area. I was a little bothered, however, by the seeming paucity of insects compared to the years prior to management. I visited the glades again several times afterwards, and not only did insect populations in general seem to be depressed, but I never succeeded in finding D. pugionata adults on the ninebark plants. I began to worry that the prescribed burns, while clearly beneficial to the glade flora, might have had a negative impact on the glade’s insect populations.

I’m happy to report that, at last, I have found the beetles again. I returned to the glades in early May this year and, for the first time since 1987 I found the adults of this species—five in all (a typical number for the many dozens of plants checked) and right in the same areas where I had so consistently found them 25–30 years earlier. This does much to allay my concerns about the ability of these beetles to persist in the face of prescribed burning (though I remain convinced that this management technique should be used more judiciously in our state’s natural areas than it has in recent years), and I’m happy to have these new photographs of the species, which are a decided improvement over the old scanned slides taken nearly 30 years ago!

REFERENCES:

MacRae, T. C. 1991. The Buprestidae (Coleoptera) of Missouri. Insecta Mundi 5(2):101–126.

Nelson, G. H. 1975. A revision of the genus Dicerca in North America (Coleoptera: Buprestidae). Entomologische Arbeiten aus dem Museum G. Frey 26:87–180.

Nelson, G. H., D. S. Verity & R. L. Westcott. 1982. Additional notes on the biology and distribution of Buprestidae (Coleoptera) of North America. The Coleopterists Bulletin 35(2) [1981]:129–151.

Copyright © Ted C. MacRae 2012

Science Outreach in Action

/ Ted C. MacRae / 5 Comments

This evening I had the distinct pleasure of presenting to the Missouri Master Naturalist™ program, a community-based natural resource education and volunteer service program for adults whose mission is to “engage Missourians in the stewardship of our state’s natural resources through science-based education and volunteer community service.”  The purpose of this organization is to develop a corps of well-informed volunteers to provide education, outreach and service to benefit natural resources and natural areas management within the community. Master Naturalists receive training and contribute volunteer service to become a certified Master Naturalist™.

There are several chapters serving different areas of the state—my presentation was made to the Miramiguoa Chapter serving Franklin County in east-central Missouri. My talk was titled, “Tiger Beetles of Missouri,” and, as an “expert” in my chosen field, attendees received advanced training credit in addition to the basic training they receive in more general aspects of Missouri ecosystems. It is tempting to think that attendees were there just to get the credit, but what I found was one of the most engaged and interested audiences to which I’ve had the pleasure to speak in quite a long time. Naturally, it is not difficult for me to show a lot of passion when I get to present on something as dear to my heart as tiger beetles, but as a presenter I feed off audience enthusiasm as well. As a result, the combination of subject and audience engagement made for a fun discussion, and I only hope the audience enjoyed the 90 minute session as much as I did.

I write about this because I see Science Outreach by practicing scientists as critical to advancing appreciation of and participation in science by the general public—not just because I think they will have fun, but because a science-friendly community tends to make community and policy decisions favorable to and based on science. You might call it my brand of politics! I’ve been heavily involved in science outreach for many years now, talking to everyone from pre-schoolers to secondary school science classes to natural history organizations. The specifics of my message are tailored to the audience, but the underlying principle is the same—to help the audience gain appreciation of entomology in particular and science in general. I think I will chalk up tonight’s presentation as another win!

For those interested, here is a link to a PDF version of the presentation, which provides the best ‘snapshot’ look at the tiger beetle fauna of Missouri available so far:

Miramiguoa – May 2012 – TB of Missouri

Copyright © Ted C. MacRae 2012

One-Shot Wednesday: Upside down bee fly

/ Ted C. MacRae / 12 Comments

Bombylius sp. cf. mexicanus | Scott Co., Missouri

This has got to be one of the strangest photos I’ve ever taken. Three weeks ago after visiting Sam A. Baker State Park (and photographing the scorpionfly featured in last week’s One-Shot Wednesday post), my dad and I visited a couple of sand prairie remnants in the Mississippi lowlands of extreme southeastern Missouri. I was hoping to see (and photograph) some individuals of the unique population of Cicindela scutellaris that occurs in that part of the state—apparently disjunct, this populations shows an intergrade of characters typical of subspecies C. s. lecontei to the north and C. s. unicolor to the south. I’ve photographed this population before, but those photographs were taken with a small (though quite good) point-and-shoot camera before I acquired my current dSLR camera setup.

Unfortunately, temperatures were quite cool that day, and no beetles were seen at either of the two locations we visited where I’ve seen good populations in past years. When I don’t find what I’m looking for, I start noticing other things, one of which was this very fresh-looking bee fly (order Diptera, family Bombyliidae) resting on the sandy ground. I’ve not really attempted to photograph many bee flies—they are as skittish and difficult to approach as the tiger beetles I adore but, unlike the latter, not a subject of my research and, thus, harder to justify spending inordinate amounts of time attempting photographs. This one, however, was sitting so nicely on the ground, and with no tiger beetles around to demand my attention I thought I would give it a shot (pun intended!). I carefully assembled my rig and slowly crouched down to attempt a photograph, but before I could get in position the fly spooked and tried to fly away. As it took off, however, it hit a plant and fell to the ground on it’s back. As it laid there,seemingly stunned, I got myself into position and took a quick shot to make sure I had the settings and exposure that I wanted. In that regard, I couldn’t ask for better, but of course what I really wanted was a photograph of the fly right-side up, resting on its feet rather than its back. Just as I was considering what to do next, the fly abruptly righted itself and flew away, leaving me with this single, rather unconventional photograph.

After perusing the bee fly pages at BugGuide, I was fairly certain this was something in the tribe Bombyliini, with the genera Bombylius and Systoechus being the likeliest candidates. Apparently the location of the r-m vein on the wing is an important distinguishing character between these genera, but I wasn’t quite sure about its location on the wing in this photograph. Nevertheless, some of the comments under the different species in these two genera suggested that members of Bombylius tend to be active as adults in the spring, while those of Systoechus tend more towards fall. I sent the photo to dipterist Joel Kitts at University of Guelph for his opinion—he confirmed that it belonged to the genus Bombylius and suggested its appearance was consistent with that of B. mexicanus—many thanks Joel!

Copyright © Ted C. MacRae 2012

Friday Flower: Phacelia purshii

/ Ted C. MacRae / 2 Comments

Phacelia purshii (Miami mist) | Sam A. Baker State Park, Wayne Co., Missouri

It’s been rather a long time since I’ve featured a botanical subject here, so it seems a good time to resurrect my “Friday Flower” meme with this delightful little wildflower seen on my birthday field trip a few weeks ago. Phacelia purshii (family Hydrophyllaceae), also known as Miami mist, is one of only four species in this rather large genus (159 species in North America according to the USDA Plants Database) found in Missouri. Though the flowers are small, their deeply fringed petals are quite striking. The late Dan Tenaglia¹ notes at his Missouriplants.com website that the species is limited in Missouri to the extreme eastern portions of the state—the plant shown here was one of several I saw in rich, bottomland forest along Big Creek at Sam A. Baker State Park in Missouri’s southeastern Ozark Highlands.

¹ Dan Tenaglia was not only an expert botanist but a enthusiastic cyclist. He died in February 2007 after being struck by a car while riding his bicycle. Dan’s wife has kept Missouriplants.com up and running since then in honor of his passion for plants. You can help support its maintenance by making a donation to the “Dan Tenaglia Foundation”: 1416 Victoria Avenue, Opelika, Alabama 36801.

This particular woods is one of the richest I’ve seen in the state, and in the past two years I’ve featured a number of interesting plants (Phlox bifida and Tradescantia longipes), invertebrates (Drosphila sp., Magicicada sp., Calosoma scrutator, Pleuroloma flavipes, Graphisurus triangulifer, G. fasciatus, Arrhenodes minutus, Neoclytus scutellaris, Corydalus cornutus and Panorpus helena) and even snakes (Crotalus horridus and Agkistrodon contortrix phaeogaster) from there. This year marks the third consecutive birthday that I’ve visited these woods, and since I’ve found something I’ve never seen before each time (hint: just wait till you see what I still have coming from there!), I have a feeling the trend will continue next year as well.

Copyright © Ted C. MacRae 2012

One-Shot Wednesday: Panorpa helena scorpionfly

/ Ted C. MacRae / 14 Comments

Panorpa helena, male | Wayne Co., Missouri

Last month I introduced a new meme called One-Shot Wednesday as a fun outlet for those occasional instances where I was able to fire off just one shot of an insect before it took off. At the time I guess I was hoping it was a meme that I wouldn’t need to use frequently, as I really do like to get more than just one shot of the insects that I photograph. Eventually, however, I decided it might actually encourage me to attempt photographs of insects that I wouldn’t normally try to photograph—not because I don’t find them attractive or interesting, but rather the fear of becoming too distracted and missing opportunities for the types of insects that I prefer to photograph. Freeing myself from the “need” to spend inordinate amounts of time with every subject I try to photograph might actually make me more willing to fire off more shots willy-nilly. Most of these shots probably won’t be anything special, but a few should turn out pretty good—and what better way to get more practice and experience?

Today’s feature is my first attempt at something in the order Mecoptera. I am admittedly a novice when it comes to scorpionfly taxonomy, but after perusing The Mecoptera of North America, an excellent website by Norm Penny (Collections Manager at the California Academy of Sciences and specialist in the taxonomy, biology, and biogeography of the Mecoptera and Neuropterida), I’m fairly confident that this male represents the common and widespread species Panorpa helena Byers, 1962. Penny includes Missouri in the distribution of six species of this monogeneric family, but the three complete bands across yellow wings and presence of an anal horn on the sixth abdominal tergum seem to support my identification (although I suppose examination of the male genitalia would be required for conclusive identification).

Frankly I was surprised I even got this shot. I see scorpionflies commonly in dense, moist woods throughout Missouri—this one was seen in wet bottomland forest along Big Creek in Sam A. Baker State Park in the southeastern Ozark Highlands—and have noted their tendency to flit nervously through dense foliage when approached. I already had the camera out and with the proper lens attached, so I thought I’d take a shot—I got this one reasonably well-composed, focused, and exposed shot before it flew deeper into the foliage. That was good enough for me (I had other quarry on my mind…), so I didn’t bother to try to track it. That was on April 23 (my first official day as a ‘senior citizen’—harrumph!), and it’s interesting to note that this is nearly two weeks earlier than the first date of occurrence (May 4) recorded for the species at Penny’s website.

Copyright © Ted C. MacRae 2012

Adult male Hentzia palmarum jumping spider

/ Ted C. MacRae / 3 Comments

Hentzia palmarum, adult male | Scott Co., Missouri

A brief break from photos from Argentina. Last week—just a few days after returning from my 8-week absence—I visited two of the sand prairie preserves in Missouri’s southeastern lowlands to try to photograph individuals from the unique, disjunct population the Festive Tiger Beetle (Cicindela scutellaris) found down there. Spring was well underway in the area, but several days of cold and rain seemed to have sent the tigers into their burrows until warmer temperatures returned. I spotted some Hibiscus lasiocarpus plants growing along the edge of a low wet spot adjacent to the prairie, so I started peering into their still unfurling leaves in hopes of finding the jewel beetle Paragrilus tenuis that utilizes the living stems of plants of this genus for larval development, but even they seemed to be awaiting balmier days. As I peered down into the leaves of one plant I notice a flick of movement, and carefully peeling apart the leaves revealed this adult male of the diminutive jumping spider Hentzia palmarum. Something was odd about this spider, and I finally realized the little guy was missing one of his characteristically enlarged and darkened front legs.

Note the elongated chelicerae.

Despite its missing leg, I became determined to photograph this spider. It certainly did not wish to be photographed, and perhaps that is the reason why. I gently snipped the leaf it was sitting on and held it in front of the camera, but every time I turned the leaf towards the camera it cowered and zipped around to the backside. Several times it attempted to flee by jumping off the leaf, but each time I pulled it back up by its thread before it hit the ground and lowered it back down onto the leaf again. Eventually I got a few shots I could live with. Of course, then I found this photo by Thomas Shahan (he describes it as “not a great photo…”) and almost felt embarrassed to show these here. Maybe I’d better stick to photographing tiger beetles!

The enlarged and conspicuously colored front legs of the males almost certainly serve some function in courtship. However, there seems to be no discussion of this in a recent revision of the genus (Richman 1989), and my further search for information about this only turned up one paper by Crocker & Skinner (1984). I really couldn’t understand anything the paper said, so for now I’m left with my presumptions that the legs are used as flags of sort—both to females to signal his availability and willingness as well as other males with more threatening intentions.

REFERENCES:

Crocker, R. L. & R. B. Skinner. 1984. Boolean model of the courtship and agonistic behavior of Hentzia palmarum (Araneae: Salticidae). The Florida Entomologist 67(1):97–106.

Richman, D. B. 1989. A revision of the genus Hentzia (Araneae: Salticidae). Journal of Arachnology 17:285–344.