Cicindelidae

Tiger beetles. Adults are agile predators in open areas such as stream banks and beaches; a few species are wingless and on tree trunks. Larvae are ambush predators living in vertical tunnels of soil or wood.

It’s always a happy day…

/ Ted C. MacRae / 7 Comments

072_066_0400_cover…when the latest issue of The Coleopterists Bulletin arrives in my mailbox. On this occasion it was the December issue of Volume 66—nine papers and eight scientific notes filling 84 pages of beetle awesomeness. It’s pure elytral ecstasy! I presume I am like most subscribers—rapidly scanning the Table of Contents on the back cover to see if any deal directly with my preferred taxa. Yes! Two papers dealing with Buprestidae (jewel beetles), one on Cerambycidae (longhorned beetles), and one on Cicindelinae (tiger beetles)—a real bonanza. After that, a more cursory look through the rest of the Table of Contents to see what other papers look interesting enough to at least scan through.

For me the most interesting are the two Buprestidae papers, with Hansen et al. documenting new state records, larval hosts, and biological notes for 47 North American species and Westcott & Murray reporting the introduction into the U.S. of yet another Eurasian exotic (Trachys minutus) and its apparent establishment in Massachusetts. As the current “keeper” of distributional records and host plant associations for North American jewel beetles (along with Rick Westcott, Salem, Oregon), I will be busily updating my database over the next few days to reflect these new records. I am a great fan of “notes” papers such as these (and am, in fact, currently finishing a similar manuscript with co-author Joshua Basham, who is also a co-author on the Hansen et al. paper). However, I do have a few quibbles—Hansen et al. report Agrilus  quadriguttatatus as a new record for Tennessee, but it is already known from that state, and Cercis canadensis (eastern redbud) is reported as a new larval host for Anthaxia (Haplanthaxia) cyanella despite the prior records from that host by Knull (1920) and Hespenheide (1974). More puzzlingly, the authors record Agrilus lecontei celticola from locations in eastern Tennessee despite guidance from me on several occasions that this subspecies, while perhaps distinctive in Texas, transitions broadly across Louisiana and Mississippi  with the nominate subspecies. As such, material from eastern Tennessee cannot be regarded conclusively to represent this subspecies (and I remain unconvinced even that the subspecific distinction is warranted). Lastly, in recording Actenodes simi from Tennessee, the authors mention that the closest previous record is from Missouri with no specific locality mentioned (Fisher 1942), even though I recently recorded several specific locations for the species in eastern and southern Missouri (MacRae & Nelson 2003). The overall impression is that the authors are not fully versed in recent literature on Buprestidae and have instead relied exclusively on the recent Nelson et al. (2008) catalogue—known amongst buprestid workers to be incomplete and with errors—as the only source for determining the status of their records.

Among Cerambycidae, Raje et al. report the results of molecular analyses on two color forms of Sternidius alpha. This broadly distributed and highly variable species exhibits multiple color variants across its range, leading to the description of multiple subspecies that were eventually synonymized under the current name. Their analysis of the barcoding region of the cytochrome oxidase I gene, however, revealed three distinct clades among the two color forms, suggesting the potential for taxonomic significance. More work, of course, is needed from additional color morphs from different localities.

Finally, my friend Matt Brust and colleagues discuss the ovipositional behavior of numerous species of North American tiger beetles, unexpectedly finding that many oviposit only after digging some distance below the surface of the soil. This information is extremely valuable for those interested in rearing tiger beetles for description of larval stages, expanding the window of survey for species with limited temporal occurrence, and cross-breeding studies. To that end, and of greatest interest to me, they have included numerous observations from their own studies that have resulted in the development of successful protocols and rapid rearing of large numbers of larvae to adulthood.

cso 66-4Mco14.qxdActually, there is one more thing… For several years now the December issue, as a bonus, has been accompanied by the Patricia Vaurie Series Monograph as a supplement to that year’s volume. This year’s issue features a revision of the scarab genus Euphoria by Jesús Orozco, and although I have not studied it carefully it looks like a robust treatment of the group. Yes, I know that scarabs are not one of my primary interest groups, but show me a coleopterist that—regardless of the group they work on— does not stop and collect these gorgeous, colorful, flower-loving beetles whenever they encounter them and I’ll show you a coleopterist that is far too restrictive in their natural history interests! Based on examination of nearly 19,000 specimens from 67 collections, the work considers 59 valid species (ten of which are described as new) distributed throughout the Western Hemisphere. Complete with keys to species and, for each, synonymy, description, diagnosis, taxonomic history, natural history, temporal occurrence geographic distribution, and—of critical importance in my opinion—full data for all specimens examined, it is everything a good revision should be. Then there are the color plates—one full page for each species—with a large dorsal habitus view, closeups of the head, male genitalia, and color variants, a temporal distribution chart, and a map of its geographical distribution. Again, while I may not be a serious student of scarabs, you can bet that I’ll be going back through my holdings of Euphoria beetles and checking them to make sure they conform to this new standard of knowledge on the group.

REFERENCES:

Brust, M. L., C. B. Knisley, S. M. Spomer & K. Miwa. 2012. Observations of oviposition behavior among North American tiger beetle (Coleoptera: Carabidae: Cicindelinae) species and notes on mass rearing. The Coleopterists Bulletin 66(4):309–314.

Fisher, W. S. 1942. A revision of North American species of buprestid beetles belonging to the tribe Chrysobothrini. U. S. Department of Agriculture, Miscellaneous Publication 470, 1–275.

Hansen, J. A., J. P. Basham, J. B. Oliver, N. N. Youseef, W. E. Klingeman, J. K. Moulton & D. C. Fare. 2012. New state and host plant records for metallic woodboring beetles (Coleoptera: Buprestidae) in Tennessee, U.S.A. The Coleopterists Bulletin 66(4):337–343.

Hespenheide, H. A. 1974.  Notes on the ecology, distribution, and taxonomy of certain Buprestidae.  The Coleopterists Bulletin 27(4) [1973]:183–186.

Knull, J. N. 1920. Notes on Buprestidae with description of a new species (Coleop.). Entomological News 31(1):4–12.

MacRae, T. C. and G. H. Nelson. 2003. Distributional and biological notes on Buprestidae (Coleoptera) in North and Central America and the West Indies, with validation of one species. The Coleopterists Bulletin 57(1):57–70.

Nelson, G. H., G. C. Walters, Jr., R. D. Haines, & C. L. Bellamy.  2008.  A Catalogue and Bibliography of the Buprestoidea of America North of Mexico.  Coleopterists Society Special Publication No. 4, The Coleopterists Society, North Potomac, Maryland, 274 pp.

Orozco, J. 2012. Monographic revision of the American genus Euphoria Burmeister, 1842 (Coleoptera: Scarabaeidae: Cetoniinae). Coleopterists Society Monographs, Patricia Vaurie Series No. 11, 182 pp.

Raje, K. R., V. R. Ferris & J. D. Holland. 2012. Two color variants of Sternidius alpha (Say) (Coleoptera: Cerambycidae) show dissimilar cytochrome oxidase I genes. The Coleopterists Bulletin 66(4):333–336.

Westcott, R. L. & T. C. Murray. 2012. An exotic leafminer, Trachys minutus (L.) (Coleoptera: Buprestidae), found in Massachusetts, U.S.A. The Coleopterists Bulletin 66(4):360–361.

Copyright © Ted C. MacRae 2013

Mr. Phidippus gets his loot

/ Ted C. MacRae / 12 Comments
Synoptic collection of tiger beetles

Synoptic collection of tiger beetles for Mr. Phidippus.

I’m sure by now Mr. Phidippus is wondering where his loot is. You see, some months ago Mr. Phidippus won BitB Challenge Session #5 with a solid string of 1st and 2nd place finishes in that session’s five ID and super crop challenges. The top three points earners at the end of each session are offered a variety of prizes, and among the choices offered Mr. Phidippus chose to receive a small collection of beetles from my collection. However, I’ve been remiss in my follow up, with only a heavy travel schedule and seemingly endless string of commitments when I am at home to offer as excuses for such.

At long last, however, I am making things right and have put together this small synoptic collection of tiger beetles that I hope Mr. Phidippus will find useful. Some of the species selected might be common in some areas, while others are certainly found very seldomly—and even then only by those who know what they are looking for. Nevertheless, one of the most fascinating features of tiger beetles is their extreme polytopism, so even commonly encountered species can look very different depending on what part of their range they come from. A perfect example of this is Cicindela scutellaris, represented in the box above by three individuals: one from Kansas (subspecies scutellaris), one from northeast Missouri (subspecies lecontei) and one from southeast Missouri (an unusual population representing an intergrade of subspecies lecontei and subspecies unicolor). Ranging from wine-red to blue-green to brilliant red and green, they are perhaps the best example of tiger beetle polytopism gone wild!

So, Mr. Phidippus this one is for you. Congratulations again on your win, and thank you for your patience!

Copyright © Ted C. MacRae 2013

Best of BitB 2012

/ Ted C. MacRae / 23 Comments

Welcome to the 5th Annual “Best of BitB”, where I pick my favorite photographs from the past year. 2012 was one of the most intensive travel years I’ve ever had—I spent 8 weeks in Argentina from February through April, made separate trips to Puerto Rico and Arkansas in May (bracketing a personal week in California), traveled almost weekly to Illinois and Tennessee from June to September (interrupted by a personal week in Florida in July), toured the southeastern U.S. (Arkansas, Louisiana, Mississippi and Georgia—great food!) in early September, chased tiger beetles in Oklahoma, Texas and Arkansas in late September, went back to Argentina for a week in October, and capped off the travel year by attending the Entomological Society of America Annual Meetings in Knoxville, Tennessee (for the first time in more than 10 years!)—whew! While many would cringe at such a travel load, I am among the lucky few who actually get paid for doing something that is also my hobby—entomology! This gives me ample opportunity to further hone my photography skills (nine of the 13 photos I’ve selected below were actually taken while I was on business travel), resulting in two key accomplishments this year—my first ever photography talk at the ESA’s insect photography symposium and my first commercial sales (look for the BitB commercial site to go online in 2013).

Enough blather! Here are my favorite BitB photographs from 2012. Click the link in the text below the photo to see the original post. I would greatly appreciate knowing if you have a favorite (and why)—your feedback will be enormously helpful to me as I continue to learn and develop as a photographer.  For those interested, here are my previous year picks for 2008, 2009, 2010 and 2011. And, as always, thank you for your readership!

Spintherophyta (?) sp. in flower of Abutilon pauciflorum | Buenos Aires, Argentina

From  (posted 2 Feb). One of my 2012 learnings was that sometimes a photograph that is not so close is more effective than one that is as close as possible. In one of my earlier attempts at “not-so-close” macrophotgraphy, the soft colors of the flower compliment the brash shininess of the tiny leaf beetle that has been feeding on its pollen. Pink lines lead the eye directly to the subject and create a pleasing composition, and pollen grains stuck to the beetle—a distraction in some situations—add to the miniature natural history story of the photo.

Apiomerus flavipennis with stink bug prey and kleptoparasitic flies | Chaco Province, Argentina

From  (posted 11 Mar). I selected this photo solely for the complex natural history story drama it shows—stink bug (Piezodorus guildenii) feeding on soybean becomes prey of an assassin bug (Apiomerus flavipennis), with volatiles from the chemicals it emitted in a vain attempt to defend itself serving as cues to kleptoparasitic flies (families Milichiidae and Chloropidae) that benefit from the assassin bug’s labors.

Planthopper nymph | Buenos Aires Province, Argentina

From  (posted 26 Mar). Another learning that I began putting into practice in 2012 was the use of low perspective for compositional impact. The cryptic coloration of this planthopper nymph (family Fulgoridae) made it almost invisible on the branch on which it was sitting when viewed from a normal “top-down” human perspective. Getting “down under” it, however, brought the nymph to life and emphasized its unusual form.

Megabaris quadriguttatus | Corrientes Province, Argentina

From  (posted 12 Apr). I spent much of 2012 working on the “blue sky background” technique, with these weevils from northern Argentina representing one of my better attempts. Macrophotography of insects with a blue sky background involves setting exposure, ISO, and aperture to achieve two separate exposures—full flash illumination of the subject for maximum depth-of-field, and ambient light from the sky to create a clean, uncluttered, natural-looking background. In this shot I managed to achieve an almost ideal shade of blue to compliment the wild black, white and red colors of the beetles. (My one criticism of the photo is having clipped one of the beetle’s feet.)

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

From  (posted 16 May). This photo is unusual if nothing else. Focus, lighting, depth-of-field, and composition are all better than can be hoped for in a single shot, but the subject—perfectly alive—is in a most unusual position. Read the original post to find out how this happened.

Perisphaerus sp. (a pill roach) | Vietnam (captive individual)

From  (posted 27 May). White-box photography is an excellent technique for clean, uncluttered photographs of insects, but it also isolates them from their natural surroundings and limits their natural history appeal. The best white-box photos are those that highlight a key feature or behavior of the subject—in this case a pill roach’s comically conglobulating defensive posture.

Micronaspis floridana (Florida intertidal firefly) larva | Pinellas Co., Florida

From  (posted 31 July). Here is another photo whose back story played a big part in its selection. This firefly larva not only represents a rare Florida-endemic species but was also first seen by my then 12-year old nephew, who willingly accompanied me through a dark, spooky salt marsh in the middle of a humid Florida night to see what he could learn. The lesson here for budding natural historians (and old-timers like me) cannot be overstated!

Arctosa littoralis (beach wolf spider) | Lewis Co., Missouri

From  (posted 23 Aug—prelude to  posted 28 Aug). Those who follow this blog know of my obsession with close-up portraits, and while tiger beetles are the subjects I most commonly photograph in this manner, I am always on the lookout for good subjects in other taxa. This wolf spider “face” almost looks human, with “two” eyes, two “nostrils” and a shiny upper lip above huge (albeit hairy) buck teeth! It’s enough fill-the-frame spidery goodness to melt (or explode) the heart of even the most ardent arachnophobe!

Anticarsia gemmatalis (velvetbean caterpillar) egg on soybean leaf

From Life at 8X—Guide to lepidopteran eggs on soybean (posted 3 Sep). “Life at 8X” was a new series I introduced this year, featuring insects photographed at magnifications testing the upper limit of my equipment and photographic skills. Diffraction is the chief difficulty with magnifications as high as this and is the primary flaw in the above photograph. Nevertheless, such view of a moth egg on the underside of a soybean leaf provides a spectacular view of the otherwise unseen micro-world that lives right beneath our noses.

Megacyllene decora (amorpha borer) on snakeroot flowers | Mississippi Co., Missouri

From  (posted 12 Sep). This second example of “blue sky background” was taken later in the year and was considerably more difficult to capture than the first because of the larger size of the subject and resulting need for a longer focal length macro lens. Getting a well-lit, focused, and composed image with a desirable shade of blue in the background depended not only on finding the proper camera settings, but also secure body and camera bracing techniques for this completely hand-held shot.

Cicindelidia politula politula (Limestone Tiger Beetle) | Montague Co., Texas

From  (posted 28 Sep). I will go ahead and say it—this is my favorite photograph of 2012. As discussed under the first entry, panning back from the subject can allow for some very interesting compositions. This photo combines charismatic pose by a wary subject with panning back and low perspective to create an image that scores high in both natural history and aesthetic appeal.

Calosoma sayi (black caterpillar hunter) | New Madrid Co., Missouri

From Black is beautiful! (posted 7 Nov). Of course, close-as-possible can also be used to create striking photos, especially if the subject exhibits features that are best seen up close. Anything with jaws fits the bill in my book, and highlighting the mandibular sculpturing of this caterpillar hunter (a type of ground beetle) required precise angling of the flash heads for maximum effect.

Cicindela repanda (Bronze Tiger Beetle) | St. Louis Co., Missouri

From  (12 Nov). This final selection is not a rare species, but it is as close as I have come to what I consider the “perfect” tiger beetle macrophotograph—a close, low angle, lateral profile of an adult in full-stilt posture (a thermoregulatory behavior), well lit, perfectly focused, and with a dynamic but pleasingly blurred background. It’s a perfect storm of a photo that took the better part of two hours to achieve—rarely do all of these elements come together in a hand-held photograph of an unconfined tiger beetle in its native habitat.

Well, there you have it. I hope you’ve enjoyed my selections, and again please do let me know if you have a personal favorite. See you in 2013!

Copyright © Ted C. MacRae 2012

Eye to eye to eye to eye with a tiger beetle larva

/ Ted C. MacRae / 2 Comments

After the past few years of hunting tiger beetles, I’ve learned not only how to find the larval burrows but—at least for most of the species occurring in Missouri—how to identify the larvae in the field. While conclusive identifications rely upon morphological characters, a preliminary field ID is often possible based on a combination of burrow size, placement, soil type and knowledge of which species are likely to occur in a given habitat. Tiger beetle larvae don’t have the same aesthetic appeal to many people that the adults have, and for this reason many species remain undescribed in the larval stage—even the well-studied North American fauna has only about 60% of its species with the larval stages described (Pearson et al. 2006). Nevertheless, the ability to find, collect and rear tiger beetle larva remains an important part of my studies because it not only expands my survey power (most tiger beetles have more restricted temporal occurrence as adults than as larvae) but can also lead to novel findings such as previously undescribed larvae and unknown parasitoid associations.

Tetracha virginica 3rd instar larva | Mississippi Co., Missouri

Tetracha virginica 3rd instar larva | Mississippi Co., Missouri

This larva was dug from its burrow in bottomland forest habitat in the southeastern lowlands of Missouri. However, before I even saw the larva I knew it belonged to the genus Tetracha and probably represented the species T. virginica (Virginia Metallic Tiger Beetle, according to Erwin & Pearson 2008). How did I know this? First, the size of the burrow (~8 mm in diameter) excluded all but one other non-Tetracha species known to occur in Missouri—Cicindelidia obsoleta vulturina (Prairie Tiger Beetle), a species known to occur only in the dry, rocky, dolomite glades in the White River Hills region of extreme southwestern Missouri. Secondly, while T. carolina (Carolina Metallic Tiger Beetle) is also found in southeastern Missouri, that species has been associated almost exclusively with treeless habitats—at least in southeastern Missouri (K. Fothergill, personal communication). Since the burrow from which this individual was dug was found in wet, bottomland forest, chances were high that it instead represented T. virginica.

Simple, thorn-like outer hooks with much smaller inner hooks distinguish Tetracha larvae from other tiger beetle genera.

Simple, thorn-like outer hooks with much smaller inner hooks distinguish larvae of Tetracha.

Notwithstanding the circumstantial evidence, there are morphological characters that also distinguish both the genus and the species of this larva. Of primary importance are the hooks and setae on the prominent “hump” of the fifth abdominal segment. This hump is braced against the vertical wall of the larval burrow as it sits at the entrance waiting for passing prey. Once the prey is seized, the hump armature provides traction against the burrow wall, preventing the struggling prey from pulling the tiger beetle larva out of its burrow (where it would not only be ineffectual as a predator but also highly vulnerable to predation itself). Tiger beetle larvae can often be distinguished at the generic level by the shape and size of the main hooks. Tetracha larvae have four hooks—two outer and two inner—that are simple and thorn-like, with the inner hooks much smaller than and placed much closer to the outer hooks than to each other (other genera either have six hooks, or they have the outer pair 1) highly curved or 2) the inner pair larger and nearly as close to each other as to the outer hooks). There are also fine details of the pattern of the setae (smaller hairs) on the hump that identify this larva as T. virginica, but the presence of numerous hairs over the surface of the abdominal segments is a much easier character to see in the field (see first photo).

Note the white-margined pronotum and nearly equal sized simple eyes.

Note also the white-margined pronotum and nearly equal sized simple eyes.

Finally, there is that head—two pairs of large, simple eyes sitting behind gaping, cocked jaws that give them an oh so alien aspect! An often metallic, shield-like pronotum sitting behind the head, both used in concert to seal the burrow entrance as the larva lies in wait, serve to complete the alien ensemble but also offer clues to the larva’s identity. All larvae of Tetracha and closely related genera bear a distinctive rim of white around the pronotal margin, making them instantly recognizable even while still sitting in their burrow. Also useful is the relative size of the eyes, which in the case of Tetracha the second pair of eyes are nearly as large as the first pair (Amblycheila and Omus have the second pair distinctly smaller than the first, while Cicindela and related genera also have the eyes more nearly equal-sized).

P.S. This is what I was photographing when my friend Kent Fothergill surreptitiously took this photograph of me!

REFERENCES:

Erwin, T. L. and D. L. Pearson. 2008. A Treatise on the Western Hemisphere Caraboidea (Coleoptera). Their classification, distributions, and ways of life. Volume II (Carabidae-Nebriiformes 2-Cicindelitae). Pensoft Series Faunistica 84. Pensoft Publishers, Sofia, 400 pp.

Pearson, D. L., C. B. Knisley and C. J. Kazilek. 2006. A Field Guide to the Tiger Beetles of the United States and Canada. Oxford University Press, New York, 227 pp.

Copyright © Ted C. MacRae 2012

One Bad Beetle

/ Ted C. MacRae / 9 Comments

Almost every tiger beetle trip that I take has a mix of gimmes and stretch goals. That’s alright—it’s impossible to find everything every time out, and if I eschewed the common and was happy only when I found something truly rare, then I would probably find myself rather unsatisfied most of the time. For the stretch goals, however, “success” can mean many things—obviously the best case scenario is to find it in good enough numbers to allow responsible collection of an adequate series and photograph enough individuals in situ to ensure that at least a few shots will have the focus, lighting, and composition that I want. Success can also be something less than that—maybe I find only a few and don’t get a very good series, or I have trouble getting field shots and am not happy with the shots I got…or worse I don’t even get field shots! The least successful version of “success” is when I end up with just one single beetle, and the only photographs I get are very ordinary-looking shots of that one beetle in confinement. Like what happened with Cicindela decemnotata (Badlands Tiger Beetle).

IMG_3717_1080x720

Soda Lake, Wyoming—we searched theses areas of alkaline exposures but never found beetles…

Chris Brown and I knew this species would be a stretch goal when we added “Soda Lake, Wyoming” to the itinerary of our 7th Annual Fall Tiger Beetle Trip™ (location “H” on this map). Cicindela decemnotata is the westernmost representative (Rocky Mountains from the northwestern Great Plains and northern Great Basin north to Yukon) of a group of species that seem to be closely related and resemble each other in their green coloration varying degrees of red on the head, pronotum and elytra and their variably developed white elytral markings (Pearson et al. 2006). Cicindela limbalis, C. splendida and C. denverensis occur as a partially allopatric species complex further east in the Great Plains, while C. sexguttata, C. patruela and C. denikei occupy more forested regions even further to the east. On this trip we were focusing on Great Plains tiger beetles and the dune specialists of the Yampa River Valley of northwestern Colorado. Our drive from northwestern Nebraska to the Yampa Valley would skirt the eastern edge of C. decemnotata‘s distribution, so we decided to stop by Soda Lake where Matt Brust had seen the species in previous years.

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…until we started searching these small ridges of exposed sandy soil.

It took most of the morning to reach the spot, so by the time we arrived we were anxious to get out and start searching the sage brush habitat. For me it was an unfamiliar landscape—at that time my northwesternmost push for tiger beetles yet, and like many western habitats it seemed vast and unending. We were optimistic, however, because it just “looked” like good tiger beetle habitat, with ribbons of alkaline flats weaving through open brush. Of course, as time passes and one starts to recognize that they are again searching ground already covered with no sign of beetles, optimism begins to wane and searches become more deliberate. We were there for almost an hour before I heard Chris call out. He had abandoned the alkaline flats—obvious habitat it would seem—and started looking upon some slightly sandier low ridges a little further to the south. I hustled to where he was standing, and we both looked at the beetle, calmly sitting on the sand, as we deliberated our next move. Should we try to photograph it? It seemed not at all skittish—but what if we failed, it got away, and then we never saw another one? We played it safe, netted it (easily), and placed it in a vial for transfer to a container of native soil should further efforts at finding and photographing the species fail. It was perhaps another 45 minutes before we saw another beetle—I don’t know if it was just a less cooperative individual or the heat of the day had kicked in, but as soon as I started my approach it was gone. We saw another not long after, but same story. Finally we saw one last beetle that seemed to tolerate my approach to the point that I even began looking for it in the view finder—at which point it promptly zipped away. This small prospect of success only served to prolong our vain searching before we eventually we accepted defeat and tried to be happy with the single individual that we had caught and the photographs that we would take of it in its artificial home.

Cicindela decemnotata

Cicindela decemnotata (Badlands Tiger Beetle) | Soda Lake, Wyoming

Part of me really doesn’t like showing photographs of confined tiger beetles—not for any philosophical reasons, but because I just don’t like the way they look. Rarely do they exhibit the elegant stilting and other thermoregulatory behaviors that place them in much more pleasing postures when photographed in situ. Rather, they often have a “hunkered down” look that says “I’m not happy and I don’t want to be here, so I’m not going to smile for the camera!” Since these photos were taken, I have learned a few tricks to deal with confined beetles and achieve more aesthetically pleasing photographs—these include the use of much larger arenas, allowing the beetles more time to accommodate to their environs, and elevating the substrate relative to the camera (maybe a subject for a future post). In the end, however, they are still confined and can’t be passed off as anything but that.

The bold white markings, media band sharply angled and not reaching the edge of the elytra, and ''greasy'' appearance distinguish this species.

The bold white markings, media band sharply angled and not reaching the edge of the elytra, and ”greasy” appearance distinguish this species.

As an aside, tiger beetle pros Barry Knisley, Ryan Woodcock and Mike Kippenhan have recently published the results of an impressive study of this species in which a combination of morphological and molecular evidence support the recognition of four subspecific entities—three described as new (Knisley et al. 2012). The molecular analyses not only support the subspecific distinctions postulated from morphology but also suggest that populations have undergone rapid phylogenetic radiation in the recent geological past. Much of the area occupied by C. decemnotata was covered by an ice shield during the most recent glaciations and, thus, has opened up for colonization only during the past 10,000 years (Pearson and Vogler 2001). The molecular analyses showed a relatively low amount of genetic divergence within C. decemnotata populations, which combined with marked morphological differences suggests recent and rapid radiation—most likely in the wake of glacial recession. A similar situation has been observed with members of the Cicindela maritima species-group, which occupy much the same range as C. decemnotata and, presumably, have experienced similar selection pressures in the recent geological past.

REFERENCES:

Knisley, C. B., M. R. Woodcock & M. G. Kippenhan. 2012. A morphological and mtDNA analysis of the badlands tiger beetle, Cicindela (s. str.) decemnotata Say, 1817 (Coleoptera: Carabidae: Cicindelinae) with the description of three new subspecies. Insecta Mundi 0214:1–49.

Pearson, D. L., C. B. Knisley & C. J. Kazilek. 2006. A Field Guide to the Tiger Beetles of the United States and Canada. Oxford University Press, New York, 227 pp.

Pearson, D. L. and A. P. Vogler.  2001. Tiger Beetles: The Evolution, Ecology, and Diversity of the Cicindelids.  Cornell University Press, Ithaca, New York, 333 pp.

Copyright © Ted C. MacRae  2012

Where siblings mingle: Ellipsoptera marginata vs. E. hamata

/ Ted C. MacRae / 14 Comments

When Erwin & Pearson (2008) formally broke up the great genus Cicindela by elevating most of its former subgenera to full genus rank, it caused a bit of consternation amongst some North American cicindelophiles. The argument went something like, “Now we have all these new genus names to learn, and we’ll have to relabel and reorganize everything in our collections, and how do we know the names won’t change again, and we can’t even tell them apart in the field anyway, and blah blah…” Pardon me, but since when did taxonomy become more about slotting species into fixed, easy-to-learn categories and less about best reflecting dynamic knowledge of complex evolutionary relationships? In the case of Cicindela and its former subgenera, however, even these arguments don’t hold up to close scrutiny—tiger beetle enthusiasts in North America should have already been quite familiar with the former subgenera due to their inclusion in the widely accepted Pearson et al. (2006) field guide, many of which actually do present a unique suite of morphological/ecological characters that facilitate their recognition in the field, and I personally find that nomenclatural recognition of individual lineages helps my attempts to learn and understand them much more than dumping them into a large, all-encompassing genus based on superficial resemblance. As for insisting that names don’t change, well that has never been a tenet of taxonomy. Stable, yes, but fixed and immutable, no.

Ellipsoptera marginata male | Pinellas Co., Florida

Enough waxing philosophic. One of the more distinctive of the former subgenera is Ellipsoptera. Morphologically the genus is defined by details of male genitalia, but the 11 North American species are generally recognizable in the field by their relatively “bug-eyed” look and long legs (Pearson et al. 2006) and, as a group, seem ecologically tied to extreme habitats with sandy and/or saline substrates that are nearly or completely devoid of vegetation. Coastal marshes and mudflats, saline flats, sandy river banks, and deep sand ridges representing ancient coastlines are some of the habitats where species in this genus are most commonly encountered. Most of the species exhibit a fairly uniform facies but differ in the details of maculation and dorsal coloration, but two species that stand apart from the rest are E. marginata (Margined Tiger Beetle) and E. hamata (Coastal Tiger Beetle) due to the highly diffuse middle band of their elytra. These are both eastern coastal species and presumably represent sibling species that have diverged based on geographical range partitioning—E. marginata along the Atlantic Coast and E. hamata along the Gulf Coast. In the field, the two species are almost identical in appearance but nonetheless easily identifiable based on geographical occurrence. There is, however, a small stretch of coastline—the lower Gulf Coast of Florida—where the ranges of the two species overlap and geography alone isn’t sufficient for species determination.

Ellipsoptera hamata lacerata male | Dixie Co., Florida

Fortunately, despite their strong resemblance to each other, field identifications in areas where these species co-occur are still possible due to the presence of small but distinct sexual characters present in one species but absent in the other. Close examination is necessary to see the characters (or their absence), so it is best to net a few individuals and examine them in the hand or, as I have done here, look at them through the viewfinder of a camera. The photos in this post include the male and the female of both species, each showing the presence or absence of the distinguishing character.

Ellipsoptera marginata female | Dixie Co., Florida

In most tiger beetles, male individuals are distinguished by a number of secondary sex characters, but easiest to see in the field are the brush-like pads on the underside of the front tarsi (“feet”). Males of E. marginata and E. hamata are further distinguished from each other by the presence (E. marginata) or absence (E. hamata) of a distinct tooth on the underside of the right mandible. Photo 1 above shows a male E. marginata from Pinellas Co., Florida, and the tooth is easily seen in that relatively distant view. Photo 2 above shows a male E. hamata lacerata (Gulf Coast Tiger Beetle)—the Floridian subspecies, and while a small bump can be seen on the underside of the right mandible, it is not nearly as well developed into a distinct tooth as in E. marginata.

Ellipsoptera hamata lacerata female | Dixie Co., Florida

Female tiger beetles, on the other hand, lack the brush-like tarsal pads present in the males and are further distinguished by the “mesopleural coupling sulcus”—an area just behind the side of the pronotum that receives the male mandible during mating and is thus devoid of setae (compare the females in Photos 3 and 4 with the males in Photos 1 and 2). Neither E. marginata nor E. hamata females possess the mandibular tooth found in E. marginata males, but they can be distinguished from each other by their elytral apices. In E. marginata females (Photo 3), the elytra are curiously “bent” at the tips, forming a distinct indentation at the apex of the elytra where they meet, while female E. hamata (Photo 4) lack this indentation.

Are there other tiger beetle sibling species groups for which you would like to see comparative posts such as this one?

p.s. I completely neglected to mark yesterday’s 5th anniversary of Beetles in the Bush! I don’t know how I missed a milestone as big as five years—hopefully my ability to provide interesting content is faring better than my middle-aged memory!

REFERENCES:

Erwin, T. L. and D. L. Pearson. 2008. A Treatise on the Western Hemisphere Caraboidea (Coleoptera). Their classification, distributions, and ways of life. Volume II (Carabidae-Nebriiformes 2-Cicindelitae). Pensoft Series Faunistica 84. Pensoft Publishers, Sofia, 400 pp.

Pearson, D. L., C. B. Knisley and C. J. Kazilek. 2006. A Field Guide to the Tiger Beetles of the United States and Canada. Oxford University Press, New York, 227 pp.

Copyright © Ted C. MacRae 2012

Persistence Pays

/ Ted C. MacRae / 6 Comments

For the past three years I’ve crisscrossed the country in search of some of North America’s rarest tiger beetles, each time hoping to get that “perfect” photograph of an unconfined beetle exhibiting natural behavior in its native habitat. I’ve managed to get photos of most, though there are a few that I wish I could do over, but the only one that I think really comes close to the ideal I have in my mind is this one of Cicindela formosa generosa, featured in the ESA 2013 World of Insects Calendar (and, ironically, taken only about 5 miles from my home).

A consequence of all this attention to uncommon species is that I’ve somewhat neglected getting good photographs of some of our most common tiger beetles. One of these is Cicindela repanda (Bronze Tiger Beetle), which can be found near almost any body of water throughout the bulk of eastern North America. This summer I resolved to correct that situation, but I found this to be more difficult than anticipated. The first time I tried to photograph the species was when I encountered them in late July on a wide, open beach along the Mississippi River on a hot, summer day. I found the beetles almost completely unapproachable due to the extreme heat and lack of any cover that could be used to my advantage. I had better luck in mid-August when I attracted some individuals to an ultraviolet light that I had setup one night at a spot further north along the river. Those photos were acceptable technically but lacking otherwise, primarily because the beetles didn’t assume any of the charismatic poses associated with the thermoregulatory behaviors exhibited by active beetles in the middle of a hot summer day. Finally, at the end of August, I encountered the species yet again on a small patch of sandy/muddy river bank along the Mississippi River just south of St. Louis. It was another hot day—quite hot actually—but with the help of some features of terrain I was finally able to get that photo of the species that I’ve been wanting.

Cicindela repanda (Bronze Tiger Beetle) | St. Louis Co., Missouri

I like this photo for a number of reasons. The beetle is nicely profiled while paused “tall” on its front legs (a common posture on hot days as they try to lift themselves up off the hot soil surface), the angle is low, and the subject and foreground are well focused in front of a nicely blurred backdrop of rocks. It is these rocks that actually helped me get this photo. I had chased several individuals down on the open sand for some time, but since the day was as hot as my first attempt and I wasn’t having any better luck. Every now and then one of the beetles that I was “working” would fly up into this rockier area, and I noticed that I was able to get closer to these beetles because I was able to stay lower as I made my approach. I began preferentially working beetles towards the rocks and finally got one that settled down and started showing normal searching behaviors despite the fact that I was already in fairly close range. At that point, it became a matter of waiting for the beetle to “lower his guard” while I assumed a shooting position, and as soon as it began acting normal I slowly closed in and began taking shots.

Getting close is a process, as these successive shots demonstrate.

This collage shows the four shots immediately preceding the final photo and how each shot brought me a little closer to the beetle (and that final composition that I wanted). The beetle was still in search mode as it crawled up the side of one rock and I began taking photos, but upon reaching the top it paused and lifted itself up high on its front legs. I knew I would have 5, 10, maybe 15 seconds at the most to capture this pose before it began moving again, so I closed in slowly but assertively and fired a shot every couple of seconds until I got the one that I wanted. At that moment, the beetle flew away, and although I tried for another 20 minutes or so I was unable to get another beetle back up on the rocks for more shots. How fleeting success can be!

Copyright © Ted C. MacRae 2012

How to deal with a crappy photo of a beautiful beetle

/ Ted C. MacRae / 21 Comments

One thing I’ve discovered after trying my hand at insect macrophotography for the past three years is that I take a lot more photos than I can possibly post. As a result, I tend to focus my efforts on more recent photos, especially those that have some kind of interesting natural history story to tell. Photos that don’t get posted soon after I took them tend to accumulate in my virtual “not yet posted” files, and periodically I need to browse through them to re-acquaint myself with any that I may have since forgotten about. Not all of these “other” photos are bad or uninteresting—they just happened to be taken at a time when I had other photos that I was more interested in using. Admittedly, however, there truly are some rather ugly photos in these archives, and the older they are the more frequently I find myself asking, “Why in the heck did I even keep that photo?” (hopefully this indicates improvement in my standards of what constitutes a photo worth keeping).

Cicindela limbalis | nr. Laramie, Wyoming

There is, however, a lesson here to be learned, and that is don’t be too quick to send to the recycle bin a photo that at first sight appears not worth keeping. Take, for example, this photograph of Cicindela limbalis (Common Claybank Tiger Beetle). This pretty little species is broadly distributed in Canada and the northern U.S. from New England across the Great Plains to the eastern edge of the Rocky Mountains. Different populations show differing degrees of maculation, and here in Missouri the species is nearly immaculate. I found the individual in the above photo in Wyoming’s Medicine Bow National Forest as an example of the more completely maculated forms. However, since it was the only individual I saw in that location I didn’t try to photograph it in the field. Instead, I captured it and photographed it later in the “studio” (my hotel room). Sadly, this was in September 2010 when I was still a rank beginner in terms of insect macrophotography, and as a result I was far less versed on such details as lighting and composition than I am now. I’m ashamed to say that I thought this photo was “good enough.”

Of course, by today’s standards that is one crappy photo! If it wasn’t the sole photo that I have from that population I wouldn’t hesitate to throw it away. However, since I’ve been putting some effort recently into honing my Photoshop skills, I thought I would see if I could “rescue” from this crappy photo a halfway decent one. I did this as follow:

  • I opened the “Levels” tool, clicked on the “Set White Point” button, and touched the cursor to an area of the upper background. This not only eliminated most of the gray tinge in the background but also brightened up the beetle quite a bit. I brightened the beetle even more by pulling the left slider button in the “Input Levels” box a little more to the right (12). In the case of this photo, such levels adjustments were sufficient, but in some cases I might also slightly reduce shadowing using the “Shadows/Highlights” tool (2–10% is usually enough) or adjust color using the “Adjust Hue/Saturation” tool (whether you increase or decrease saturation, a light touch is best).
  • With the background brightened up, the debris spots were even more visible and needed to be cleaned up. This was easily accomplished with the “Spot Healing Brush” tool. I keep the size setting as small as possible for each spot while still encompassing the entirety of the spot. Debris spots next to or on the surface of the beetle are better dealt with using the “Clone Stamp” tool—this tool is a little more involved than the Spot Healing Brush, since a source point needs to be selected for each spot. However, it is more effective than the Spot Healing Brush for spots that are in areas where the background is not uniform. Again, I use the smallest size possible and carefully consider the source point for each clone to achieve the best results.
  • The last major problem with this photo was its composition. If I were to take it again today, I would angle the front of the beetle higher in the photo and not clip the middle and hind tarsi or antennal tip as I did in this photo. There is not a lot (though there is a little) that can be done about the clipping, but I used the “Straighten” tool to change the angle of the beetle by clicking on the tip of the abdomen and dragging the cursor to somewhere between the lower front leg and antenna. This resulted in a more pleasing pose for the beetle, but of course it also created triangular areas of blank canvas on each side that had to be dealt with. To do this, I cropped the edges of the photo to remove as much of the blank canvas as I could without cropping off any more of the beetle (I did end up cropping a little bit of the left hind leg), then used the Clone Stamp tool to fill the remaining blank areas with white background (this is much more difficult when the background is not as uniform as in this photo). Careful cloning is required in areas that are close to the beetle to prevent unintended alterations, and in this case I even had to clone in a fake lower tarsus for the middle leg and antennal tip for the left antenna to fill gaps that I could not crop. Cloning in new body parts is not always possible, and even when it is possible it’s not easy; however, with care and practice reasonable results can be achieved. In the case of this beetle it was not too difficult since the body parts that needed to be cloned were just short extensions of already blurred parts.

Lastly, I used typical “Unsharp Mask” settings to sharpen the photo, and here is the final result:

This photo won’t win any awards, but it is a completely serviceable illustration of the species.

This is still not a great photo—in addition to the clipping, the focus is a tad too deep and the beetle has assumed that dreaded “ground hugging” pose that I so detest with confined subjects. Nevertheless, I wouldn’t be ashamed to use this photo if none better were available.

What alternative techniques would you have used on reworking this photo?

Copyright © Ted C. MacRae 2012