Tiger Beetles at Florida’s “Road to Nowhere”

(continued from the previous post, Tiger Beetles Agree—It’s Hot in Florida!)

During the time that I explored the pine sandhill habitat at Withlacoochee State Forest in Citrus County, I kept close watch for any individuals amongst the dozens and dozens of Cicindela abdominalis (Eastern Pinebarrens Tiger Beetle) that I encountered that might exhibit the deeply pitted rather than smooth elytral surface that would identify it as the closely related Florida-endemic, Cicindela scabrosa (Scabrous Tiger Beetle).  However, no such individuals would be seen (my first tiger beetle failure of the trip), and having already spent more than two hours at the site I decided it was time to move on the the “Road to Nowhere.”

"Road to Nowhere," 11.1 mi S Jena on Hwy 361, Dixie Co., Florida

The Road to Nowhere is a tidal marsh (also known as “coastal salt marsh”) near Steinhatchee in Dixie County (11.1 mi S Jena on Hwy 361).  Although I was not aware of it prior to my August visit, this locality has achieved legendary status among tiger beetle enthusiasts because of the great number of species that can be seen there—as many as 6–10 species in the right season.  Being a coastal wetland with moist, saline substrates, these would include such species as Cicindela trifasciata ascendens (Ascendent Tiger Beetle), Habroscelimorpha severa (Saltmarsh Tiger Beetle), the rarely collected H. striga (Elusive Tiger Beetle), and Eunota togata togata (White-cloaked Tiger Beetle), in addition to Ellipsoptera marginata (Margined Tiger Beetle) and E. hamata lacerata (Gulf Beach Tiger Beetle) which I had already found a few days earlier.  As I found the highway leading to the spot and begain to drive its upper reaches, I looked longingly at the barren sand exposures along the sides of the road thinking that C. scabrosa, already known from the area (Choate 2003) must be there.  However, it was well into the afternoon hours by then, and having already failed to find the species at Withlacoochee State Forest, I decided I should press on and see what the Road to Nowhere had to offer.

Cicindela (Cicindelidia) trifasciata ascendens—Ascendent Tiger Beetle

Almost immediately I began seeing tiger beetles.  The first species I saw was C. trifasciata ascendens—rather common on areas of the flats close to the water’s edge.  I recognized them instantly, as I had not only seen this species some years ago in south Texas, but also in southern Missouri as a lone vagrant (Brown and MacRae 2005).  The dark brown dorsal coloration and thin, sinuous, S-shaped middle maculation are diagnostic for the species (Pearson et al. 2006).  While it was by now late afternoon, the heat of the day had not yet begun to subside, and the beetles were extremely active and flighty.  The difficulty in approaching them closely enough for photographs was exacerbated by the wet, muddy substrate and incessant drone of tenacious mosquitoes intent on breaching my invisible shield of DEET.  Eventually, however, and only due to one decidedly more cooperative individual (above), I succeeded in getting a few shots with which I was happy. 

Habroscelimorpha severa—Saltmarsh Tiger Beetle

Far less common than C. trifasciata ascendens, but equally skittish, was the impressive H. severa.  I have also seen this species before in south Texas, though not in great numbers, and its shiny green surface with maculations reduced to small spots at the middle and rear of the elytra are unmistakealbe.  It was the hardest to approach of the species I saw, and the above (only slightly cropped) photograph is as close as I was able to get (it is also the only photograph from the field session that was good enough and close enough to keep).  This species tends to be most active in the morning and again in the evening, so most of my late-day efforts focused on this species—in fact, it was almost too dark to see by the time I finally quit my attempts at photographing the species.  I brought back one live individual and took some “studio” photographs after I returned home, but I’m still not any happier with them than this lone field shot.

Ellipsoptera hamata lacerata—Gulf Beach Tiger Beetle (reduced maculations)

When I first saw the species represented by the individual in the above photograph, I had not a clue as to its identity—the dark elytra with only a marginal band was unlike anything I would have expected to see.  Quickly thumbing through my “bible” (Pearson et al. 2006), I kept stopping at the plate containing Cicindela marginipennis (Cobblestone Tiger Beetle).  I knew this was impossible, as that species is restricted to several disjunct cobblestone habitats further north.  I collected the specimen for a voucher, keeping it alive for studio photographs, but it wasn’t long before I saw another similar-looking individual.  I decided I must be overlooking something, so after getting photographs and collecting the specimen for another voucher I went back through Pearson.  This time I focused only on the species that could possibly occur here, and realized that it was simply E. hamata lacerata with its normally diffuse middle elytral maculations highly reduced (traces of the middle band can be seen in the photograph).

Ellipsoptera marginata—Margined Tiger Beetle

Ellipsoptera marginata was the most abundant species at this location, and on this day I succeeded in getting a nice photograph of a female with her distinctively downbent elytral apices (see closeup photograph in this post).  This species is very similar to E. hamata, with which it co-occurs along the Gulf Coast of peninsular Florida, but can be immediately recognized by the bent elytral apices (female) or distinct tooth on the underside of the right mandible (male).  Both of these species are distinguished from all other species in the genus by the diffuse middle maculation of the elytra. 

At least two additional species occur at this site, one of which (E. togata) I saw but a single individual of and was unable to photograph, and the other (H. striga) which I did not see.  In fact, the Road to Nowhere is apparently “the” spot for finding the latter species, which occurs predominantly at night and is seen primarily by its attraction to ultraviolet lights.  While I would have liked to stay after dark and setup lights to see this species, I had neither the time nor the equipment to do this.  It may, after all, have been too late in the season anyway—since my visit I’ve heard stories from other tiger beetle aficionados who say the whole area can be filled with collectors from all over the country with their blacklights and bucket traps and someone yelling “striga!” every hour or so.  No such scene developed during my visit, so I suspect my visit was on the late side of the season and that the 5 species I did see represents a pretty good day regardless.  The long drive back to St. Petersburg marked the end of my tiger beetle exploits in Florida, at least for this year.

For another tiger beetling experience at Road to Nowhere, read this post by Doug Taron, who visited the site even later in the season (October).  Although he didn’t see as many tiger beetles, he does provide some interesting details regarding the shady origins of this place.

Photo Details: Canon EOS 50D, ISO 100, 1/250 sec.
Habitat: Canon 17-85mm zoom lens (landscape, 66mm), f/9, natural light.
Insects (except E. marginata): Canon 100mm macro lens (manual), f/22–25, MT-24EX flash w/ Sto-Fen diffusers.
E. marginata: Canon MP-E 65mm 1–5X macro lens (manual), f/16, MT-24EX flash w/ Sto-Fen diffusers.


Brown, C. R. and T. C. MacRae. 2005.  Occurrence of Cicindela (Cicindelidia) trifasciata ascendens (Coleoptera: Cicindelidae) in Missouri. Cicindela 37(1–2):17–19.

Choate, P. M., Jr. 2003. A Field Guide and Identification Manual for Florida and Eastern U.S. Tiger Beetles.  University Press of Florida, Gainesville, 224 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 2009

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Florida Metallic Tiger Beetle

Tetracha floridana

Tetracha floridana (Florida Metallic Tiger Beetle), dorsal view

In my previous post, I showed some photographs of the larva of an undetermined species of tiger beetle that I collected from its burrow in dry ground adjacent to a coastal salt marsh near St. Petersburg, Florida. I had assumed the larva belonged to the genus Cicindela or one of its former subgenera and was suprised to learn that this assumption was incorrect when the adult emerged 2 months later. Looking back at the photos, however, I realized that the photos and the information I gave regarding its location and habitat contained all of the necessary information to identify this larva. Five points to Mike Baker, who correctly deduced the genus (Tetracha), and in fact the larva represents Tetracha floridana (Florida metallic tiger beetle).

Hump of 5th abdominal segment, showing simple, thorn-like inner and outer hooks

The hump of the 5th abdominal segment bears simple, thornlike hooks.

The larva can be placed in the genus Tetracha by virtue of its simple, thorn-like hooks (in other eastern U.S. tiger beetle genera, the outer hooks are distinctly curved).  Two other genera of Nearctic tiger beetles that do not occur in Florida also bear simple hooks—Omus (Night-stalking Tiger Beetles, occurring along the Pacific Coast) and Amblychelia (Giant Tiger Beetles, occurring in the central and southwestern U.S.); however, the former bears three rather than two pairs of hooks, and the latter has the inner and outer hooks distinctly separated from each other.


Tetracha floridana (Florida Metallic Tiger Beetle), lateral view.

Four species of Tetracha occur in the U.S., three of which occur in Florida—T. carolina (Pan-American Big-headed Tiger Beetle), T. floridana (Florida Metallic Tiger Beetle), and T. virginica (Virginia Big-headed Tiger Beetle).  However, T. carolina is restricted in the state to the panhandle and interior of the peninsula along rivers and in disturbed sparsely vegetated areas (Choate 2006).  Of the two remaining species, T. virginica is widespread throughout the southern two-thirds of the eastern U.S. and occurs in a variety of habitats (Pearson et al. 2006), while T. floridana is restricted to salt marsh and mud flat habitats along the Gulf coast of Florida from Dixie County south to the Keys (Choate 2006).  While the widespread occurrence and generalist tendencies of T. virginica might suggest that it is the more likely choice, the locality and habitat match precisely with T. floridana.


The anterior lobes of the apical lunules are divergent.

Tetracha floridana is very similar to T. carolina and was long considered a subspecies of that more widely distributed species until Naviaux (2007) elevated it to species rank in his revision of this large genus.  Tetracha floridana is distinguished from T. carolina by the divergent anterior lobes of the apical lunules (photo above) and the uniformly black to dark green elytra that lack any violet or coppery reflections in the anteriolateral regions (photo below) (Choate 2003).

The anteriolateral areas of the elytra lack violet or copper reflections

The anteriolateral areas of the elytra lack violet or copper reflections.

I was happy as heck when I saw the first newly emerged adult in the rearing container, as this is a true Florida endemic.  I have encountered the two other eastern U.S. species commonly under street lamps and at building lights here in Missouri—T. virginica throughout the state and T. carolina in the southeastern lowlands, where it appears to reach its northern limit of distribution.  A fourth U.S. species in the genus, T. impressa (Upland Metallic Tiger Beetle) (T. affinis” in earlier works), occurs in northern Mexico and the Lower Rio Grande Valley (LRGV) of south Texas (Erwin and Pearson 2008).  Although I have not yet encountered it on any of my many trips to the LRGV (all of which pre-date my current cicindelophily), I understand it is regularly attracted to building and street lights in Brownsville (Pearson et al. 2006).  I believe I will have to go down there again and verify this for myself someday.

Feasting on a corn rootworm larva.

Feasting on a corn rootworm larva.

The last photo in this series illustrates the unique feeding behavior of these beetles, which despite their terrifyingly toothy mandibles are strictly fluid feeders.  The long, sharp mandibular teeth function primarily in prey subdual and in slicing and shredding their tissues, while the maxillae (second pair of feeding appendages behind the mandibles) and labium (fused third pair of appendages) comprise an “oral mill” that masticates the prey and and rolls it into a bolus.  Two brush-like structures can be seen behind the mandibles in the photo above—these are part of the maxillary laciniae and apparently function in containing and shaping the bolus as it is being masticated.  While this occurs, proteolytic enzymes are extruded from the midgut and mixed with the bolus to liquify its digestible components, which are then sucked into the beetles tiny mouth by the action of a pharyngeal pump.  Like the larva, the adult beetle thus “chews” but does not swallow its prey—a manner of feeding that is not too unlike that of spiders and other arachnids (sans the venom).

Photo details:
All photos: Canon EOS 50D, manual mode, ISO-100, 1/250 sec, MT-24EX flash w/ diffuser caps.
Photo 1: Canon 100mm macro lens w/ 68mm extension tube, f/25, 1/2 power flash.
Photo 2: Canon MP-E 65mm 1–5X macro lens, f/16, 1/8 power flash.
Photos 3–5: Canon 100mm macro lens w/ 36mm extension, f/18–f/22, 1/4 power flash.
Photo 6: Canon 100mm macro lens w/ 68mm extension, f/20, 1/2 power flash.


Choate, P. M., Jr. 2003. A Field Guide and Identification Manual for Florida and Eastern U.S. Tiger Beetles.  University Press of Florida, Gainesville, 224 pp.

Choate, P. M., Jr.  2006.  Tiger Beetles of Florida, Cicindela spp., Megacephala spp. (Insecta: Coleoptera: Cicindelidae).  University of Florida, IFAS Extension Service Circular EENY-005, 5 pp.

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.

Naviaux R. 2007. Tetracha (Coleoptera, Cicindelidae, Megacephalina): Revision du genre et descriptions de nouveaus taxons. Mémoires de la Société entomologique de France 7:1-197.

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 2009

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Anatomy of a Tiger Beetle Larva

My first experience looking for tiger beetles in Florida had gone well.  Despite its small size and urban surroundings, the narrow strip of coastal scrub and saltwater marsh along the intracoastal waterway behind my sister-in-law’s condominium boasted a robust population of what I took to be a single tiger beetle species.  The specimens I collected and photographs I took would later reveal that two co-occurring and closely related species were present: Ellipsoptera marginata (Margined Tiger Beetle) and E. hamata lacerata (Gulf Beach Tiger Beetle).  I had spent close to two hours under the August sun observing and photographing the beetles before I decided that I had given the preserve a thorough enough look.


As I was heading back, I noticed a little bit of high ground alongside a red mangrove thicket and went over to give it a look.  As I approached I saw something I hadn’t yet seen that day – tiger beetle larval burrows.  Larval burrows, especially larger ones such as these were, are unmistakeable – almost perfectly circular (slightly cut out on one edge) and smoothly beveled around the perimeter.  There were a number of burrows clustered on the small bit of high, dry ground, and my first thought was that their inhabitants represented the same (what I thought was a single) species that I had encountered so commonly that day as adults.  I then reasoned, however, that more likely they represented another species whose adults are active later in the season – perhaps one of the so-called “spring/fall” species whose larvae typically reach maturity during the heat of summer.  The size of the burrows (~5mm dia) suggested they were inhabited by 3rd instar larvae (the final instar before pupation), in which case it may be possible to rear a few to adulthood – if I could get at them. I tried fishing (Pearson and Vogler 2001) a few holes with a grass blade but didn’t get any bites, so I decided to watch for awhile and see if any of the larvae, believing the danger of my approach had passed, would reappear at the tops of their burrows.  Waiting for tiger beetle larvae to appear is a crap shoot – maybe they’re active, and maybe they’re not, and crouching in the stifling summer air of a coastal marsh in Florida is not an easy thing to do for very long.  Fortunately my wait was short, as within a few minutes I saw one re-appear at the top its burrow.  I slowly got out my knife and moved to place the tip on the soil about 1″ from the burrow at a 45° angle for an attempted tunnel block (Pearson and Vogler 2001), but it spooked and dropped back down into its burrow before I could get then knife in place.  No matter, I knew it was in there now and that it would likely reappear if I could muster the patience.  I positioned the knife and waited – crouched under the baking Florida sun, until when it did re-appear I plunged the knife into the soil with authority.  It was a good jab – I had blocked its retreat without injuring it, and a quick flip of the knife popped out the soil plug and exposed the startled larva, flipping vigorously in a vain attempt to escape before settling down amidst its unfamiliar, exposed surroundings.


For those of you who have never seen a tiger beetle larva, they are among the most other-wordly creatures one can imagine.  The large, heavily sclerotized head bears two long, sickle-shaped, upward-pointing mandibles and up to three pair of highly-acute eyes whose arrangement on each side conveys the image of a “face” with congenital birth defects.  The top of the head is flattened to lie flush with the surrounding soil as the larva sits at the top of its burrow, and huge, powerful mandibular muscles fill the cranial cavity.  The remainder of the body – long, narrow, and cylindrical – hangs from the head at a 90° angle down into the burrow and is unremarkably grub-like, save for a curious hump on the dorsal side of the 5th abdominal segment.  Close examination of the hump reveals an intricate pattern of forward-facing hooks and spines that function in anchoring the larva against the side of its burrow to prevent struggling prey from dislodging it.  The life of a tiger beetle larva is a life of waiting – unlike the adults who run down their prey, the larvae sit in their burrows and wait for prey to come to within lunge’s reach.  While the eyes of most grub-like insects detect little more than light and dark, those of tiger beetle larvae are densely packed with photoreceptors that permit detailed focusing and depth perception for detecting whether potential prey has ventured close enough to their burrow (Pearson et al. 2006).  When that happens, they strike with lightning speed, plunge their mandibles into their prey, and drag it down into the depths of their burrow where it is summarily dispatched with a few bites of their powerful mandibles.  Larvae consume they prey in a manner similar to that of adults in that they chew but don’t swallow their prey. Rather, they secrete digestive secretions containing proteolytic enzymes that begin digesting the prey extra-orally as they chew.  The resulting bolus is masticated and its liquid components sucked out until nothing but a dry wad of indigestable chitin remains, which is spat out of the burrow (Pearson and Vogler 2001).


Looking at this strange insect, it occurred to me that I had not yet attempted macrophotographs of a tiger beetle larva out of its burrow, and this would be a good opportunity to get more practice with my Canon MP-E 65 mm macro lens – a lens with incredible magnification capabilities, but one that is also a bit of a temperamental beast to use hand-held in the field.  The subject was unusually cooperative, perhaps too stunned by its sudden predicament to know what to do, and as I took the photographs I focused in particular on characters of the head and dorsal hump (often useful in identifying tiger beetle larvae, at least to genus).  Time was growing short once I finished taking photographs, so I placed the larva in a vial and returned the following day to extract a chunk of native soil to place in a rearing container, managing to collect two more larvae as well (unfortunately, one became instant “prey” for the other.  Note to self: when placing multiple tiger beetle larvae in a container of soil, seal the artificial burrows into which you place each one!).  I paid little further attention to the photographs, other than to transfer them onto my computer and add metadata upon my return to St. Louis.  I didn’t know what species the larvae represented, but I assumed they were something in the genus Cicindela or one of its several former subgenera.  However, had I studied the photos and considered the locality and habitat, I would have realized that my assumption was incorrect¹.  That realization would come in surprise fashion two months later when the two adults emerged within a few days of each other…

¹ Ten points to whoever can use this information to arrive at an identification before my next post 🙂


Photo details:
All photos: Canon EOS 50D, manual mode, ISO-100, 1/250 sec, MT-24EX flash w/ diffuser caps.
Photo 1: Canon 100mm macro lens, f/22, 1/4 power flash (photo slightly cropped).
Photos 2-4: Canon MP-E 65mm 1-5X macro lens f/16, 1/8 power flash.


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.

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 2009.

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(My) Introduction to Florida Tiger Beetles

On the last day of July, I hopped into my stuffed-to-the-brim SUV and began the +1000-mile drive to St. Petersburg, Florida.  I had with me my camera and my collecting gear, but also my bike, some beach wear… and my family!  No, this was not a collecting trip, but a family vacation.  We would be staying at my sister-in-law’s condo with my niece and enjoying typical Florida vacation fare – beaches, Disney World, sightseeing.  I even brought my road bike along to enjoy some pancake-flat terrain (a rarity around St. Louis) for a nice change of pace.  Still, I can be rather single-minded when it comes to opportunities for bug collecting, and summer in Florida presents opportunities galore!  Virtually everything there is different, and while I have been to Florida a number of times, my visits have all been during spring and prior to my more recent interest in tiger beetles.  It would be a family vacation, but still I would find a way to sneak off a couple times and satisfy my compulsions, and while the girls talked about Disney World and the beach, visions of Cicindela abdominalis, C. highlandensis, C. scabrosa, Ellipsoptera gratiosa, E. hamata lacerata, E. hirtilabris, E. marginata, Habroscelimorpha dorsalis, H. severa, and H. striga danced through my head!

I wouldn’t have to go far to find my first Florida tiger beetles.  My sister-in-law’s condo is in Seminole (west side of St. Petersburg peninsula), and as my niece and her husband showed us around after our arrival, they pointed out the “wild area” off their back patio next to the intertidal waterway and suggested, innocently, that I could go bug collecting back there.  In such a developed urban/tourist area, I figured it must be highly disturbed, dominated by exotics, and offering little in the way of quality habitat for the serious bug collector.  However, that night, as a cacophony of nasal queenks from the area made it clear that a healthy population of what I presume to be green treefrogs were thriving in the area, I reconsidered my skepticism and decided to take a quick look a day later.  What I found was a small but high-quality strip of coastal scrub and saltwater marsh bordering the intracoastal waterway, with thickets of red mangrove (Rhizophora mangle) along the water’s edge, black mangrove (Avicennia germinans) “woodlands” in the high scrub areas, and moist, briney, barren ground in between (Photo 1).  The whole area couldn’t have been more than a hundred yards wide but extended along the length of the waterway, and a wooden sign as I entered the area indicated it was a bona fide, albeit private, nature preserve established as part of the condominium development.

Intertidal salt marsh, Tara Cay Sound Nature Preserve, Seminole, Florida

Intertidal salt marsh, Tara Cay Sound Nature Preserve, Seminole, Florida

Within minutes after entering the preserve I saw the first tiger beetle.  I didn’t know what it was, and my first stalking efforts were woefully inadequate.  I saw another one a few minutes later and got within net handle distance but muffed the swing.  A few feet further along the path and onto an exposure by the water revealed several individuals, one of which I was finally able to capture after several clumsy misses.  I hadn’t yet memorized key characters for all of the species I had the potential to encounter, but I could see in the hand that this individual almost certainly belonged to the genus Ellipsoptera (Ellipsed-winged Tiger Beetles) because of its resemblance to E. macra (Sandy Stream Tiger Beetle) and E. nevadica knausii (Knaus’ Tiger Beetle), which I had photographed earlier this year in Missouri and Oklahoma, respectively.  With one now in the hand as a studio backup, I began my efforts to obtain field photographs.  The beetles were extremely wary, with fast running and strong flight capabilities that made them very difficult to approach.  It was only their abundance and my dogged persistance that allowed me to finally get close enough to one (Photo 2) to fire off a sequence of frames.  I then spent some time collecting a voucher series – finally getting a beat on their behavior and able to capture them with a little more efficiency despite their ultra-wariness before concentrating on getting more photographs of different individuals (including those shown in Photos 3 and 4).

Ellipsoptera marginata - Margined Tiger Beetle

Ellipsoptera marginata - note "tooth" under right mandible of this male

Ellipsoptera marginata - Margined Tiger Beetle

Ellipsoptera marginata - another male, with a distinctly bronzed pronotum


Ellipsoptera hamata lacerata - Gulf Beach Tiger Beetle (mate guarding)

I returned to the condo after a couple of hours – completely drenched (remember, it was August in Florida!). When I had the chance to consult my “bible” (Pearson et al. 2006), I learned there there were two possibilities: Ellipsoptera marginata (Margined Tiger Beetle), occurring along the Atlantic seaboard from Maine to the Gulf coast of Florida; and Ellipsoptera hamata lacerata (Gulf Beach Tiger Beetle), resembling and closely related to E. marginata and occurring along the Gulf Coast from Florida to Texas.  Both species inhabit coastal beaches, mud flats and salt marshes, and their distributions overlap along Florida’s Gulf Coast. While they are easily distinguished from other species in the genus by the distinctively diffuse middle band of the elytra, distinguishing between the two requires examination of the male right mandible (marginata bears a distinct tooth on the underside, hamata does not) or female elytral apices (marginata curiously bent down at a 90º angle, hamata not).  At this point, I didn’t know if I had one species or two – and if I did have two, did I have photographs of both (and would I be able to identify them)?

Fortunately, closer examination of the voucher series I collected revealed both species present, and even more fortunately I had managed to get photographs of both.  The individual in Photo 2 is a male, and the angle of the photograph clearly reveals a distinct tooth on the underside of the right mandible, identifying it as E. marginata.  Photo 3 is another male, and although the angle doesn’t afford a view of the mandibles, what can be seen is a bronze cast to the pronotum – in my voucher series, all of the E. marginata specimens have a bronze cast to the pronotum, while the E. hamata lacerata specimens exhibit an olive cast. This suggests that this individual also represents E. marginata. In Photo 4, no tooth can be seen on the male mandible, but the angle of the photo doesn’t necessarily make it visible were it to exist.  The male does, however, exhibit an olive cast on the pronotum, and the female elytral apices show no indication of being bent down as would be expected for E. marginata (see Photo 5 below of E. marginata photographed a few days later at another locality).  As a result, the individuals in Photo 4 can be identified as E. hamata lacerata.

Ellipsoptera marginata - female elytral apices showing curiously "bent tips"

Ellipsoptera marginata - female elytral apices showing curiously "bent tips"

Of the 19 vouchers that I collected, 15 represent E. marginata and 4 represent E. hamata lacerata.  This exemplifies the challenges of field identification and photography of insect species in unfamiliar places.  Had I been satisfied with photographing only one or two individuals of what I thought were all the same species, I would have missed one of the species.  The experience further exemplifies the importance of adequate voucher series, as it was only a result of close examination of that series that I realized two species were present.  Based on the numbers of individuals that I collected, as well as the photographs that I took, it appears that E. hamata lacerata was much less common at that location than E. marginata. This difference in population density between two similar, co-occurring species emphasizes the importance of sampling an adequate number of individuals at a given location before concluding what species are – and are not – present.


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 2009

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