Oklahoma

Party on a pin oak

/ Ted C. MacRae / 9 Comments

In September 2012 while collecting in western Oklahoma (Weatherford) I came across this interesting scene. It had been exceedingly dry in the area, and because of this few insects were out and about in the small city park that I stopped by to check for the presence of tiger beetles. I had nearly completed my circuit of the park when I came upon a moderate-sized pin oak (Quercus palustris) tree and noticed something on the lower trunk:

Six insect species representing five families in four orders share a sap flow.

Six insect species representing five families in four orders share a sap flow on the trunk of a pin oak.

No less than six insect species representing four orders were seen all huddled together at a darkly stained sap flow. This could be the result of slime flux, a bacterial disease that usually affects deciduous hardwoods that are under stress and results in darkly stained weeps on the trunk that are known to be attractive to a variety of insects. At the center sat a green June beetle (Cotinis nitida) and three bumble flower beetles (Euphoria inda)—all in the family Scarabaeidae (subfamily Cetoniinae). Covering the scarab beetles were half a dozen Texas Tawny Emperor (Asterocampa clyton texana) butterflies (family Nymphalidae, or Brushfooted Butterflies), and milling around the perimeter was a velvet ant (Dasymutilla creusa, I believe) in the family Mutillidae, an apparent flesh fly (family Sarcophagidae), and a true ant (family Formicidae). I guess this would be the equivalent to a watering hole in Africa with a lion, a hyena, a baboon, three vervet monkeys and six zebras all crouched shoulder-to-shoulder at its edge.

Euphoria sepulchralis feeds on a sap flow higher up on the trunk.

Euphoria sepulchralis feeds on a sap flow higher up on the trunk.

Further up on the trunk, yet another species of scarab beetle, a dark flower scarab (Euphoria sepulchralis) was found feeding on a smaller sap ooze. Unlike the diverse aggregation of insects on the lower ooze, this guy had managed to keep the ooze all to himself.

Cotinus nitidus | Weatherford, Oklahoma

Cotinis nitida | Weatherford, Oklahoma

Green June beetles, especially, are known for their feeding on sap oozes. The beetles are actually attracted to the odors caused by fermentation of the sap rather than the sap itself. It has been reported that the presence of alcohol in fermenting sap can affect the behaviour of insects that feed upon it, causing them to act “stupid and lethargic.” I did not see any such behavior, but I did notice that the insects were not at all skittish and loath to leave the sap.

Copyright © Ted C. MacRae 2013

Q: How do you photograph cactus beetles?

/ Ted C. MacRae / 10 Comments

A: Very carefully!

This past June I went out to one of my favorite spots in northwestern Oklahoma—Alabaster Caverns State Park in Woodward Co. The park, of course, is best known for its alabaster gypsum cavern—one of the largest such in the world—and the large population of bats that occupies it. Truth be told, in my several visits to the park during the past few years I have never been inside the cavern. The draw for me is—no surprise—it’s beetles. On my first visit in 2009 I found what is now known to be one of the largest extant populations of the rare Cylindera celeripes (swift tiger beetle), previously considered by some to be a potential candidate for listing on the federal endangered species list, and last year I found the northernmost locality of the interesting, fall-active jewel beetle Acmaeodera macra. This most recent visit was the earliest in the season yet, and as I walked the trails atop the mesa overlying the cavern I noticed numerous clumps of prickly pear cactus (Opuntia macrorhiza) dotting the landscape.

Opuntia phaecantha | Alabaster State Park, Woodward Co., Oklahoma

Opuntia macrorhiza | Alabaster Caverns State Park, Woodward Co., Oklahoma

Whenever I see prickly pear cactus anywhere west of Missouri I immediately think of cactus beetles—longhorned beetles in the genus Moneilema. A half-dozen species of these relatively large, bulky, clumsy, flightless, jet-black beetles live in the U.S., with another dozen or so extending the genus down into Mexico and Baja California, and all are associated exclusively with cactus, primarily species of the genus Opuntia. It wasn’t long before I found one, and deliberate searching among the cactus clumps produced a nice series of beetles representing what I later determined as M. armatum. The resemblance between Moneilema spp. and darkling beetles of the genus Eleodes is remarkable, not only in their appearance but also in their shared defensive habit of raising the abdomen when disturbed. The genus has been related taxonomically to the Old World genus Dorcadion, but Linsley & Chemsak (1984) regard the loss of wings and other morphological modifications to represent convergence resulting from the environmental constraints imposed by root-feeding, subterranean habits in arid environments and other situations where flightlessness is advantageous.

Moneilema armatum adult.

Moneilema armatum adult in situ on Opuntia macrorhiza pad.

I have encountered Moneilema beetles a number of times out west, including this species in Texas where it is most common, but since I have only been photographing insects for the past few years this was my first  chance to capture cactus beetle images as well as specimens. The above shot, taken with my iPhone, was straightforward enough, but I wanted some real photographs of the beetle—i.e., true close-up photos taken with a dedicated macro lens. I quickly learned that this would be highly problematic—those cactus spines are long and stiff and vicious, and these beetles are no dummies! Clearly their ability to adapt to such a terrifyingly well-defended plant has had a lot to do with the evolution of their slow, clumsy, flightless, you-don’t-scare-me demeanor. Normally when I photograph insects I do a little pruning or rearranging of nearby vegetation to get a clear, unobstructed view of the subject, and sometimes this also involves “pushing” my way into the vegetation to get the most desirable angle on the subject for the sake of composition. Not so here! In my first attempt, all I could think to do was locate a beetle sitting in repose and try to position myself in some way so that the beetle was within the viewfinder and the cactus’ spines were not impaled within my arms! The photo below shows the only shot out of several that I even considered halfway acceptable, but clearly the spines obstructing the view of the beetle were not going to be to my liking.

First attempt - looking down into plant where beetle was first sitting.

First attempt – looking down into plant where beetle was first sitting.

What to do? The beetle was behaving fairly well (i.e., it was not bolting for cover upon my approach), so I pulled out a pair of long forceps (that I carry with me for just such cases) and used them to gently prod the beetle into a more exposed position. The beetle crawled up onto one of the unopened cactus flower buds and perched momentarily, and I thought I had my winner photograph. I crouched down again, was able to get a little bit closer to the beetle than before, and fired a few shots. Looking at them in the preview window, however, left me still dissatisfied—the beetle was no longer obstructed, but the background was still jumbled, messy and dark, making it difficult for the dark-colored beetle to stand out. I would need to think of something else.

Second attempt - looking down on beetle after coaxing it up.

Second attempt – looking down on beetle after coaxing it up.

I actually take a lot of my photos with the insects sitting on plant parts that have been detached from the plant. This allows me to hold the plant in front of whatever background I choose and micro-adjust the position of the insect in the viewfinder for the best composition. This is “easier” (a relative term) with a shorter lens (think MP-E 65-mm) because the lens-to-subject distance matches almost perfectly the distance between my wrist and my fingers, allowing me to rest the camera lens on my wrist while holding the plant part with my fingers to “fix” the lens-to-subject distance. These beetles, however, are much too big for the MP-E 65-mm, so I had to use my longer 100-mm macro lens. The longer lens-to-subject distance does not allow resting the lens on my wrist, so I must come up with other ways of bracing myself and the subject to minimize movement. Detaching the pad on which the beetle was resting (and if you’ve never tried to detach an Opuntia cactus pad from its parent plant while trying not to disturb a beetle sitting on it, I can tell you it is not an easy thing), I also discovered that the pad was quite heavy and that holding it with the same forceps that I had used to prod the beetle (because of its vicious spines) was yet another unanticipated difficulty. I decided the best way to deal with it would be to get down on one knee in front of the plant, rest my arm on my other knee with the cactus pad extending out in front of me, and photograph the beetle with the plant as close in the background as possible to achieve a lighted and colored background that would help the beetle stand out. Following are examples of those attempts.

Third attempt - holding detaching pad with forceps for better view.

Third attempt – holding detaching pad with forceps for better view.

Detached allows even better close-ups.

Detached allows even better close-ups.

Better for sure, especially the latter, closer one. Still, I wasn’t satisfied—the backgrounds still just had too much clutter that detracted from the beetle and complicated the lighting. I decided to go for broke—why not go for the blue sky background, the cleanest, most natural and aesthetically pleasing background possible! This actually was my first thought when I saw the beetles, but I could never find one on a high enough plant that was growing in a situation where I was able to crouch low enough to get the angle with the sky in the background. By this time my arm was quite weak from holding the heavy cactus pad and squeezing the forceps firmly, and as I contemplated how I could possibly hold the pad up towards the sky and take the shots without being able to rest the camera on my arm I had an idea. Why not rest my arm on the camera? Specifically on top of the flash master unit atop the camera. I adjusted the camera settings for blue sky background, positioned the cactus pad in the forceps so that the pad (and beetle) were hanging down from the forceps but still in an upright position, pointed the camera to the brightest part of the sky (a few degrees from the sun), and then held the cactus pad out in front of the camera with my arm resting on the flash master unit. It worked! My arm still got tired quickly and needed frequent breaks, and I had to do a number of takes to get the exposure settings and composition I was looking for, but the photo below represents my closest approach to what I envisioned when I first knelt down to photograph these beetles. A clear view of the beetle, on its host plant, with lots of nice value contrast between beetle, plant and background.

Fourth attempt - holding detached pad up against sky for cleaner background.

Fourth attempt – holding detached pad up against sky for cleaner background.

Once I had the technique figured out, I was able to get some really close-ups shots as well, still, however, with enough blue sky in the background to make it clean and pretty…

Zooming in with sky background gives a nice, clean close-up.

Zooming in with sky background gives a nice, clean close-up.

…as well as playing with some unusual compositions that one can afford to try only after they are confident they have gotten the required shots. I am particularly fond of the following photo, in which the beetle appears to be “peeking” from behind its well-defended hiding place on its host plant.

Having a little fun with the close-ups - he's peaking!

Having a little fun with the close-ups – he’s peaking!

If you have any experiences photographing these or other such “well-defended” insects (without resorting to the white box!) I would love to hear about them.

REFERENCE:

Linsley, E. G. and J. A. Chemsak. 1984. The Cerambycidae of North America, Part VII, No. 1: Taxonomy and classification of the subfamily Lamiinae, tribes Parmenini through Acanthoderini. University of California Publications in Entomology 102:1–258 [preview].

Copyright © Ted C. MacRae 2013

Honey Locust Borer

/ Ted C. MacRae / 5 Comments
Agrilus difficilis | Beaver Dunes State Park, Beaver Co., Oklahoma

Agrilus difficilis | Beaver Dunes State Park, Beaver Co., Oklahoma

Conditions for collecting didn’t look very promising when I awoke on Day 4 of my early June trip to northwestern Oklahoma. After collecting at Alabaster Caverns State Park the previous day, I had traveled a few hours further west during the evening with plans to collect at Beaver Dunes State Park the following morning. However, heavy rain during the night and lingering sprinkles during the morning had me thinking it might be a lost day. By noon, however, the rain had completely abated, and though the sky still hung low and gray I decided I had nothing to lose by at least trying. I knew quickly that I’d made the right decision, as within minutes of arriving at the park I began seeing jewel beetles (family Buprestidae) landing on my beating sheet. Hackberry (Celtis sp.) was abundant along the roadways and supporting great numbers of individuals in the genera Chrysobothris and Agrilus.

This species is associated almost exclusively with honey locust (Gleditsia triacanthos).

This species is associated almost exclusively with honey locust (Gleditsia triacanthos).

By the time I reached the back end of the campground, I’d collected rather large series of the hackberry associates when I noticed a dying honey locust (Gleditsia triacanthos) tree in one of the campsites. Honey locust (and fabaceous trees, in general) is favored by several species of jewel beetles—at least a dozen species have been recorded in the literature reared from its branches, and another dozen species have been collected on it as adults. As a result, when jewel beetles are active it’s always a good bet that some will be found on honey locust when present, especially if the trees are stressed or dying. I walked up to the tree—a fairly large one—and scanned the lower branches overhead to see if I could notice any activity. I did not, but I nevertheless placed my beating sheet underneath one of the branches, gave the branch a quick “whack” with the handle of my net, and lowered the beating sheet to have a look. To my surprise, I saw at least 50 adults of the jewel beetle species, Agrilus difficilis, sitting on the beating sheet. Because of the cloudy conditions and cool, moist air, the beetles were not very active and did not immediately zip off the beating sheet as they would have had the day been sunnier and warmer, so I was able to rather easily collect a decent series of the beetles without any trouble. I had never seen the beetles so numerous, however, so I continued to beat a few more branches—each yielding just as many adults as the previous. I was astonished by the fact that the beetles were so abundant on the branch, yet I had not seen them even when I specifically looked for the presence of jewel beetles in the branches prior to beating them. Taking another look at the branches, I was able to visually detect just a few individuals, and those only with great difficulty, until I pulled the branch down and was able to look at it up close.

Relatively large size, coppery-purple color without spots on the elytra, and the presence of lateral white patches distinguish this species.

Large size, coppery color, no spots on elytra, and presence of lateral white patches distinguish this species.

Honey locust became a rather popular landscape ornamental tree in the eastern U.S. after the development of thornless cultivars, and while at first the tree seemed to be relatively free of insect pests, A, difficilis has proven to be one of several insects that have adapted to these landscape plants and occasionally cause economic damage. Trees in urban landscapes are often planted in suboptimal sites and suffer from stress to a much greater degree than their native counterparts, and the beetles take advantage of the lowered defensive capabilities of these stressed trees to gain entry. Larvae mine beneath the bark and damage the cambium layer, interfering with movement of water and nutrients. Trees in later stages of attack usually exhibit branch dieback and D-shaped holes in the trunk and main branches where adults have emerged from the tree. In severe cases infestation by this species can result in death of the tree. As mentioned above, there are twelve other species of jewel beetles that have been reared from the wood of honey locust. All of these have been reared only from dead wood rather than living trees, but adults of these species might, nevertheless, be encountered on living trees. They include three species (A. egeniformis, A. fallax, and A. pseudofallax) that might be confused with A. difficilis; however, the latter is easily distinguished from these and other congeners by its relatively large size, coppery color with purple luster, absence of any spots or pubescent lines on the elytra, and distinctive patches of white pubescence along the sides. As with most wood boring beetles, chemical control of the adults or larvae is usually not feasible once an infestation has already begun—the best method to avoid infestations in landscape trees is proper site selection and optimal care to prevent stress that reduces the ability of the tree to fend off attack.

Copyright © Ted C. MacRae 2013

An interesting flightless May beetle

/ Ted C. MacRae / 7 Comments

I suppose you are an entomologist?

Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name. No man can be truly called an entomologist, sir; the subject is too vast for any single human intelligence to grasp.

Phyllophaga cribrosa | Gloss Mountain State Park, Major Co., Oklahoma

Phyllophaga cribrosa | Alabaster Cavern State Park, Woodward Co., Oklahoma

I suppose the above quote from The Poet at the Breakfast Table, by Oliver Wendell Holmes, Sr., applies just as well to those who would call themselves coleopterists, for restricting oneself to the study of beetles diminishes by scarcely more than half the known diversity of all insects. I still dare to call myself a coleopterist, but I’m the first to admit that while there are a few groups of beetles that I know very well, there are many more that I know only superficially and some that befuddle me completely. An example of the latter is May beetles (family Scarabaeidae, genus Phyllophaga). With more than 400 species in North America (Ratcliffe & Jameson 2010), it is one of the most speciose genera in our fauna. Not surprisingly, species identifications can be very difficult, oftentimes relying on examination of male and female genitalia.

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The flightless adults are most often found on the ground or low vegetation.

Not all species of Phyllophaga, however, are difficult to identify. The species shown here—P. cribrosa—is rather easily recognized within the genus by its oval, convex shape, shining black coloration, cribrose (perforated like a sieve) surface, 10-segmented antennae, and flightless nature. The resemblance to certain darkling beetles (family Tenebrionidae) is striking, although I suspect this may be a result of convergent adaptation to dry habitats rather than mimicry (Kaufman & Eaton 2007). While most species of Phyllophaga are nocturnal and capable of flight, adults of P. cribrosa are flightless and can be found crawling on the ground and clinging to low vegetation during the day. I found these beetles this past June at several locations in northwestern Oklahoma.

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The distinct elytral furrows distinguish P. cribrosa from closely related species.

There are at least two other closely related species in the genus (i.e., P. epigaea and P. zavalana) that resemble P. cribrosa; however, both of these species are restricted to Texas, and they lack the distinct longitudinal elytral furrows exhibited by P. cribrosa. The species is said to be an occasionally serious pest of crops (Luginbill & Painter 1953), although I suspect that in most cases this results from new plantings of crops in former grasslands because of the limited dispersal abilities of the beetles.

REFERENCES:

Eaton, E. R. & K. Kaufman. 2007. Kaufman Field Guide to Insects of North America. Houghton Mifflin Harcourt, 391 pp.

Luginbill, P., Sr. & H. R. Painter. 1953. May beetles of the United States and Canada. U.S. Department of Agriculture Technical Bulletin 1060, 102 pp,

Ratcliffe, B. C. & M. L. Jameson (eds.). 2010. Generic Guide to New World Scarab Beetles (available at: http://www-museum.unl.edu/research/entomology /Guide/index4.htm).

Copyright © Ted C. MacRae 2013

The one that got away!

/ Ted C. MacRae / 13 Comments

It was disappointing to reach Black Mesa, the furthest west destination for my June collecting trip through northwestern Oklahoma, only to discover that the whole region was dry as a bone. I spent an hour or so sweeping yellow roadside composites and got a few Typocerus confluens—a reasonably uncommon longhorned beetle, and another hour’s worth of beating oaks and junipers in the area produced a grand total of three Chrysobothris ignicollis, a very common jewel beetle associated with junipers in the southern Great Plains. This in glaring contrast to the veritable smörgåsbord of jewel and longhorned beetles I had encountered earlier in the week at Beaver Dunes, Alabaster Caverns, and Gloss Mountain State Parks. I had planned to spend at least a full day in the Black Mesa area—maybe two if the collecting was good, but as it was I couldn’t justify spending even another minute in the area. Unable to resist the siren call of more productive areas back to the east, I decided to cut my losses and return to those areas to close out the week. It was still early afternoon, and if I left immediately I would arrive back at Beaver Dunes (from where I had left just the previous evening) with at least a few hours to pad my series and perhaps even find something new.

Oberea oculaticollis Say 1824 | Beaver Dunes State Park, Beaver Co., Oklahoma

Oberea oculaticollis Say 1824 | Beaver Dunes State Park, Beaver Co., Oklahoma

One area I wanted to take another look at was the small lake near the campground. I had beaten a few willow-feeding Agrilus spp. from the black willow (Salix nigra) and Poecilonota cyanipes from the cottonwoods (Populus deltoides) surrounding the reservoir. I desired better series of what I had collected the previous day, so I retraced my steps and beat most of the same trees I had beaten before. While I did quite well with P. cyanipes on the cottonwoods, again only a few Agrilus were beaten from the willows. I had nearly completed the circuit around the lake when I walked up to a small willow sapling that I had not sampled the previous day, gave it a whack over my sheet, and onto the sheet fell a nice longhorned beetle that I didn’t immediately recognize. At first I thought it was a species of Mecas due to the dense covering of gray pubescense, but the long and narrow form seemed much more agreeable with the genus Oberea. At any rate, seeing that it was something new for me I placed it back on a willow branch and began taking photos of it.

The dark integument and dense, grayish pubescence distinguish this species.

The dark integument and dense, grayish pubescence distinguish this species.

It was late in the day, and the beetle was unusually calm and cooperative and allowed me to take a number of shots, from which I have selected a few to show here. Once I had my fill of photographs, I slipped it into a vial for safe-keeping while I disassembled and stowed my camera equipment, and after I was finished I pulled out the vial with one hand and reached for my bottle dropper of ethyl acetate with the other. I have a technique to unscrew both the vial and the bottle with the fingers of the hand that is holding them, lifting both caps simultaneously, dropping a few drops of ethyl acetate into the vial, and again simultaneously placing both caps back in place and screwing them shut. This minimizes the time the cap is off the vial while the insect is in it, thus minimizing the chance of the insect escaping during the process. In this case, however, as I was trying to do this a dog-pecker gnat flew right at my eye, and I instinctively swiped at it with my left hand—the one holding the vial with the beetle in it! Of course, the cap was off, and the beetle when sailing out of the vial and immediately took flight. All I could do is just stand there dumbfounded at my stupidity. I did go back and beat the same sapling (and every other willow tree) on my way back in a last ditch effort to recollect the species, but fortune was not with me at this time.

This adult on black willow (Salix nigra) is the first indication of its host plant.

This adult on black willow (Salix nigra) is the first indication of its host plant.

Once I returned home and had a chance to examine the photos more carefully, I learned that I had photographed Oberea oculaticollis Say 1824, a longhorned beetle distributed in central North America from Manitoba to Texas and distinguished, not surprisingly, by its dark integument and dense, grayish pubescence (Chemsak & Linsley 1995). Not only have I never before encountered this species, but it is also completely lacking in my collection. As far as I can tell, no host information has been recorded for this species, so my collection of an adult on willow might be the first clue as to its host plant. Without a voucher specimen, however, I am reluctant to publish the record and will have to keep this spot in mind for possible future collection of the species.

REFERENCE:

Linsley, E. G. & J. A. Chemsak.  1995. The Cerambycidae of North America. Part VII, No. 2: Taxonomy and classification of the subfamily Lamiinae, tribes Acanthocinini through Hemilophini. University of California Publications in Entomology 114:1–292.

Copyright © Ted C. MacRae 2013

Rattlesnakes may be present!

/ Ted C. MacRae / 6 Comments

I don’t know what it is, but even though I am first an entomologist I am also a sucker for snakes. Well, not just any snakes, but rattlesnakes. It must have something to do with my psyche—my favorite color is black, when it comes to music I choose metal (Slayer, anyone?), and I have a collection of replica fossil hominid skulls… in my office! At any rate, when I decided to return to Gloss Mountain State Park near the end of my early June collecting trip to Oklahoma, I also decided to make a real effort to find an adult western diamondback rattlesnake. Why did I decide to do this (other than my psyche)? Because I had seen a juvenile there earlier in the week but still hadn’t seen an adult, and there is an area in the park surrounded by signs that read “CAUTION. Rattlesnakes may be present! Stay out of the tall grass. Don’t reach into holes. Stay on marked trails. Be observant.” So, what did I do? I went in, of course!

Western diamondback rattlesnake (Crotalus atrox) | Gloss Mountain State Park, Major Co., Oklahoma

Western diamondback rattlesnake (Crotalus atrox) | Gloss Mountain State Park, Major Co., Oklahoma

Actually, I had been in the area several times already on previous visits looking for these snakes, but for some reason—perhaps the juvenile from across the road still fresh in my mind, I just had the feeling that this time I was going to find one. One always enters cautiously at first, watching their every step as they wade through the waist high grasses while straining to see any sign of the diamondback pattern between the clumps of vegetation or on the steeply eroding red clay slopes above. Caution eventually subsides, however, and after about 15 minutes my attentions started drifting back to looking for beetles. I had walked along most of the southern perimeter of the area when I crested a small rise and my heart was jolted by the sudden and distinctive “buzz” of a full-sized rattlesnake. I couldn’t see it, but the sound was coming from about 10 yards in front of me, so I cautiously crept forward, moving from side to side bit as I did to help me triangulate the precise location of the sound. Within a few steps I finally saw it—a nice, adult western diamondback rattlesnake! It was largely hidden from view within a heavy jumble of vegetation—no hope for useful photographs, so I extended the telescoping handle of my insect net to its full 7-ft length and used it to carefully move away as much of the screening vegetation as I could. The snake rattled vigorously as I did this, its head always following the red grip at the end of the handle but never striking. That 7-ft distance was about as close I could comfortably get, and my 100-mm macro lens is the longest lens I have in the kit, so the full snake shot shown above and some similar shots were all I could really get. How I would have loved to have had a 200-mm or 300-mm lens to get some really close head shots!

I’ll admit that I tip-toed out of the area much more cautiously than I entered, but I did so with my held-held high and chest puffed out a bit knowing that, once again, persistence had paid off.

Copyright © Ted C. MacRae 2013

Tips for photographing shiny beetles on yellow flowers

/ Ted C. MacRae / 15 Comments

I really hate starting off this post with the following photo—typically it is the first photo in a post that readers see in syndicated feeds; however, I use it in this post to make a point. This photo was taken back in May 2009 and is among the very first photographs that I took after getting my current dSLR camera setup. I was certainly happy enough with it at the time; however, in the following years I have learned a lot about lighting and composition. Such is the curse of any photographer—the further back one goes in their portfolio, the less satisfied they are with the photos taken at a particular point in time. What was then a pretty photo of a shiny, red longhorned beetle on a bright, yellow flower is now teaching material for what not to do when taking photos of shiny beetles on yellow flowers.

One of my first photos of Batyle suturalis, taken in May 2009 | Franklin Co., Missouri

Batyle suturalis on Coreopsis lanceolata | Shaw Nature Preserve, Franklin Co., Missouri

Compare the above with the following much more recently taken photos of the same beetle species from this past June. The beetle is the same, and while the flowers are a different species they are the same intense shade of yellow, but in nearly all respects the photos are far superior to the first. What are the problems with the first photo? First, the smooth and shiny surface of the beetle combined with poor diffusion of the flash has resulted in intense specular highlights on the body of the beetle. This is especially evident in the “twin highlights” on the pronotum of the beetle that is the signature mark of the Canon MT-24EX twin flash unit when used without some type of diffuser. Secondly, the darker color of the beetle requires more flash for adequate illumination than does the much brighter yellow flower—setting the flash power high enough to fully expose the beetle resulted in overexposure of the yellow flower. One cannot even see where one petal ends and another begins. Thirdly, the top-down perspective is, well… boring, no doubt because this is far and away the most commonly used composition in photographs of insects on flowers. Lastly, in my zeal to get as close as possible to the subject, I’ve not only eliminated elements from the background that could add interest in texture to the composition but also clipped the hind tarsus of the beetle itself.

Batyle suturalis on paperflower (Psilostrophe villosa) | Alabaster Caverns State Park, Woodward Co., Oklahoma

Batyle suturalis on Psilostrophe villosa | Alabaster Caverns State Park, Woodward Co., Oklahoma

The first problem is easily addressed by using a good diffuser. It is remarkable that both Canon and Nikon have produced such incredibly effective lenses and flash units for macrophotography, yet completely ignored the demand for diffusers designed to work with them. As a result, most insect macrophotographers have resorted to various do-it-yourself (DIY) designs to fill the void. The diversity in DIY diffuser designs is as large as the diversity of insect macrophotographers, and each person has their own favorite. I have tried many different versions myself, and my current design (admittedly a fusion of ideas stolen from and Alex Wild and Piotr Naskrecki) has produced quite good results. This is evidenced in the more recent photos shown here by the very soft highlights that are spread out evenly over the body of the beetle and not concentrated into intense spots or bands.

Batyle suturalis

Portrait orientation is under-utilized in ”bug on a flower” shots.

The second problem—that of overexposure of the flower to properly expose the beetle—is handled in a simple yet somewhat counter-intuitive manner. I find yellow flowers to be especially prone to overexposure. However, it is much easier to “fix” underexposed than overexposed areas of a photo in post-processing. When a photo is underexposed, all of the data regarding color and hue is still there. It is a simple matter to increase the brightness in the image processing software to restore underexposed areas to their natural brightness. Overexposure, however, is much more difficult to correct, as once the exposure is “blown” there is no data remaining regarding the true color and hue. The only way to fix blown highlights is with the laborious process of cloning over them with nearby areas of the photo that are not blown. Perhaps some can do this quickly and with good results, but I am not one of those people. I like to selectively increase the brightness of underexposed areas using “Lighten Shadows” tool in Photoshop. Be careful, as a light hand is all it takes—overly heavy-handed adjustments look  unnatural.

Batyle suturalis

Side profiles are more interesting than ”top down” shots and allow high color-contrast backgrounds.

Finally, think about more interesting compositions for your “bug on a flower” photos than the far too commonly used top-down perspective. Getting low relative to the beetle and looking at it from the side or front not only provides a less common view of the subject but also allows for far more creativity in the overall composition. My personal preference for insects on flowers is a blue sky background, which can add a lot of value contrast to photos compared to those in which the entire background consists only of the flower on which the insect is sitting. Use of blue sky background can also further help avoid overexposure of the yellow flower, as the slightly higher ISO and slightly lower aperture settings and shutter speeds used in that technique serve to increase the amount of ambient light contributing to the photo, thereby reducing the amount of illumination needed by the flash. Side views of the insect also facilitate use of portrait orientation—an important consideration if you are interested in producing photos for potential use on journal or magazine covers (nearly always printed in portrait). Also, as you compose your photo, try backing off a bit rather than trying to focus in on the subject as tightly as possible. Backed off views not only avoid the more straightforward problem of clipping parts of the insect but can also result in much more aesthetically pleasing photographs by allowing the incorporation of other elements in the composition for balance, scale, and even a sense of motion or dynamics (as exemplified by the partially buried grass blades in this photo of the Eastern Big Sand Tiger Beetle). Photos can always be cropped in post-processing, and while excessive cropping as a way to artificially increase magnification is to be avoided, there is nothing wrong at all with slight cropping to improve composition.

Copyright © Ted C. MacRae 2013

Another new record for northwestern Oklahoma

/ Ted C. MacRae / 4 Comments

You would think that finding two new state records on the first day of my June collecting trip to northwestern Oklahoma would be fortune enough—it is rare to get two new state records on an entire trip even! As a result, I spent all morning and the early part of the afternoon working the mesquite (Prosopis glandulosa) and red-cedar (Juniperus virginiana) that dotted the barren flats at Gloss Mountain State Park to ensure good voucher series of Plionoma suturalis and Chrysobothris quadrilineata. Around 2 pm I decided I’d worked the flats as well as I could and turned my attention to the park’s main attraction, a large, gypsum-capped, red clay mesa rising 150 to 200 feet above the flats below.

Paratyndaris prosopis on dead hackberry (Celtis sp.) | Gloss Mountain State Park, Oklahoma

Paratyndaris prosopis on dead hackberry (Celtis sp.) | Gloss Mountain State Park, Major Co., Oklahoma

Red-cedar occurs on top of the mesa as well as the flats¹, but otherwise the mesa top supports a different assemblage of woody vegetation. Gone is the mesquite, a relatively “thirsty” plant that uses extraordinarily long taproots to reach subterranean water tables. In its place are western soapberry (Sapindus saponaria), hackberry (Celtis sp., poss. C. laevigata var. texana), and American elm (Ulmus americana). The soapberry was what I was most interested in, as this plant is a known host for several very uncommonly encountered species of jewel beetles in the genus Agrilus that are more commonly encountered in Texas. Hackberry also is a good host for a variety of jewel beetles, with somewhat different species occurring in Texas versus more eastern areas in the country. Perhaps, I thought, some of these Texas species could be found here as well.

¹ While native to Oklahoma, eastern red-cedar was restricted in pre-settlement times to areas not subject to fire. It is now considered an invasive species in many areas as a result of long-term fire suppression and the effects of intense cattle grazing. In the morning while I was collecting in the flats (and before I had started working the red-cedars to see what beetle was causing the branch dieback), a park ranger stopped by and asked if I knew of any way to “get rid of the cedars.” He didn’t seem very satisfied with my standard answer of mechanical removal and prescribed burning at regular intervals. He then asked about the branch dieback that was so common in the trees, and I told him I thought it was a beetle. With almost desperate optimism he said, “maybe the beetle can finish them off.” I didn’t share his optimism but didn’t say anything either.

Paratyndaris prosopis

I focused most of my early efforts on the soapberry, but nothing was landing on the beating sheet, so I then turned my attention to the hackberry. Most branches were yielding a few Agrilus spp. with each whack, but they seemed to be only commonly occurring species such as A. paracelti and A. lecontei (in this area the population should be assignable to subspecies lecontei). One can almost get “lulled to sleep” in such situations, eventually not expecting to see something different, but after working a number of trees I whacked a particularly “punky” dead branch of a tree and saw the unmistakable outline of a chunky little jewel beetle that I immediately recognized as Paratyndaris prosopis. Paratyndaris is a largely southwestern and Mexican genus of beetles that are often not well represented in collections. Paratyndaris prosopis is the only species known to venture north and east beyond Texas, but this is based on only three records: one in Red Oak, Oklahoma by the late Karl Stefan (an indefatigable collector of beetles in Latimer Co.), another at Magazine Mountain, Arkansas (a single specimen given to me by my friend Doug LeDoux), and a third from Oktibbeha Co., Mississippi (Nelson & Bellamy 2004). While not a new state record, I knew its occurrence in Major Co., Oklahoma represented a northward extension to its known range (and also opening the possibility that it might even occur as far north as Kansas). They were not common—I worked every hackberry tree I could find on the mesa and got just three specimens on the first day and a few more when I went back the next morning. However, at the end of the trip I returned to Gloss Mountain and managed to get a nicer series of close to a dozen specimens. While hackberry trees can be found in several patches on the mesa, the beetles seemed to be limited to one small area.

Paratyndaris prosopis

The occurrence of this species on hackberry and not mesquite is interesting. The type specimen was cut from a dead branch of mesquite (Skinner 1903)—hence, the species epithet, but all subsequently recorded host associations have been on oak (Quercus spp.) (Nelson 1987, Nelson & Westcott 1976), including a single specimen that I reared from a dead Q. vaseyana branch collected in the Davis Mountains, Texas. No oak occurs in the Gloss Mountains, but mesquite is common in the flats, yet it is clear from the number of specimens collected on hackberry and nothing else that the species, at least in this area, is utilizing that plant as a host. Also of interest is the date of collection—June 2, which is a full week earlier than the previous early record of June 9 (especially interesting when one considers that these are the northernmost specimens known).

REFERENCE:

Nelson, G. H. 1987. Additional notes on the biology and distribution of Buprestidae (Coleoptera) in North America, II. The Coleopterists Bulletin 41(1):57–65.

Nelson, G. H. & C. L. Bellamy. 2004. A revision of the genus Paratyndaris Fisher, 1919 (Coleoptera: Buprestidae: Polycestinae). Zootaxa 683:1–80.

Nelson, G. H. & R. L. Westcott. 1976. Notes on the distribution, synonymy, and biology of Buprestidae (Coleoptera) of North America. The Coleopterists Bulletin 30(3):273–284.

Skinner, H. 1903. Notes on Buprestidae (Coleoptera) with descriptions of new species. Entomological News 14:236–239.

Copyright © Ted C. MacRae 2013