tiger beetles

A festive (tiger beetle) birthday

/ Ted C. MacRae / 24 Comments

Last Thursday was my birthday, and as has become my custom, I took the day off and went on my ‘Annual Season Opening Birthday Bug Collecting Trip.’  One or two of you might remember how these plans were scrubbed last year by a last minute business trip, during which I discovered Pipestone National Monument in southwest Minnesota. That experience – and the post that I wrote about it – remain high among my all-time favorites. Despite that, nothing was going to derail my plans to go collecting this year, and at 5:30 in the morning I awoke to begin what would turn out to be as enjoyable and successful a day as I could hope for. I had convinced my colleagues and long-time collecting buddies Rich Thoma and Chris Brown to take the day off as well and accompany me down to the lowlands of southeastern Missouri to search for additional localities of the festive tiger beetle – Cicindela scutellaris.

Records of Cicindela scutellaris in southeast Missouri

Records of Cicindela scutellaris in southeast Missouri

As far as is currently known – C. scutellaris is represented in Missouri by three highly disjuct populations in the extreme northwestern, northeastern, and southeastern corners of the state.  The two northern populations are unambigously assignable to the northern subspecies lecontei, although their absence from areas further south in Missouri along the Missouri and Mississippi Rivers remains a mystery.  The southeastern population apparently represents an intergrade population with influences from both lecontei and the southeastern subspecies unicolor.  While this population was discovered many years ago (I first collected it in the mid-1980s), it remained known only from sand forests in Holly Ridge Conservation Area on Crowley’s Ridge.  A second population was discovered several years ago on sand exposures in the extreme western lowlands near the Ozark Escarpment when Chris Brown and I began our formal survey of tiger beetles in Missouri, and last year I succeeded in locating several populations of the beetle in the critically imperiled sand prairie relicts located along the spine of the Sikeston Sand Ridge.

cicindela_scutellaris_p1020910_2This year, we wanted to determine if intergrade populations also occurred on the Malden Sand Ridge – the southernmost expanse of sand exposures in the southeastern lowlands.  We didn’t know if they did – presettlement sand prairies were less abundant on the Malden Ridge due to its higher soil organic content.  As a result, no sand prairie relicts survived the Malden Ridge’s complete conversion to agriculture.  Undeterred, I got onto Google Maps and scoured satellite imagery of the ridge and located several spots that seemed to have potential – even though they were agricultural fields, they appeared to be of sufficient expanse and with enough sand to possibly support populations of the beetle.

So, on the morning of April 23, my ‘Annual Birthday Season Opening Bug Collecting Trip’ began by meeting up with Rich and Chris and driving the 223 miles from Wildwood to Kennett to explore several locations for a beetle based only on the suggestion of a flickering computer screen.  The first of these locations was a bust – there was a house constructed right in the middle of the site that wasn’t on the Google Map.  cicindela_scutellaris_p1020889_2Maybe the beetle occurred here and maybe it didn’t, but the last thing I wanted to do on a Thursday morning was interrupt a homeowner from their morning routine and ask them if we could collect bugs in their front yard.  Besides, there was another locality just a couple miles up the road that looked equally promising.  We found the spot and drove by slowly – it was an agricultural field that looked like it had been fallow for at least a short time, and although it did not look great (not as much sand as I had hoped) we eventually decided that since we were there we might as well take a look.  It wasn’t long before we saw an individual near the highest part of the field, and through a couple hours of exploring and digging adult burrows we had observed a limited number of adults.  Success!  The landowner happened by while we were there and graciously allowed us to continue our searches.  Through her, we learned that the field had been under soybean cultivation during the previous season.  This was good news to learn that beetles were inhabiting sand exposures on the Malden Ridge despite its complete conversion to agriculture.

Having confirmed the occurrence of C. scutellaris on the Malden Ridge, we then began driving to the next putative locality some miles north along the ridge.  Along the way, Chris spotted a rather large sand expanse in another agricultural field right next to the highway.  cicindela_scutellaris_p1020906_2Even though I hadn’t detected it in my Google Map search, it looked promising enough to explore, and so we did a quick U-turn and found a place to pull over.  This spot can only be described as the ‘festive tiger beetle motherlode’ of southeast Missouri!  Even though the field was obviously under active agricultural use, the beetles were abundant within the fairly large expanse of exposed sand within the field (photo below).  We were quickly able to collect a sufficient series to document the beetle’s range of variation and set about obtaining additional photographs.  I felt fortunate to be able to photograph this mating pair, which nicely illustrates the white labrum of the male (top) versus the dark labrum of the female (bottom) – one character that distinguishes this intergrade population from the similar-appearing six-spotted tiger beetle (C. sexguttata – commonly encountered along woodland trails throughout the eastern U.S., and with both sexes exhibiting a white labrum).  Note also how the male is holding his legs out horizontally (a behavior I’ve seen with other mating pairs) and the more heavily padded tarsi on his front legs. The latter specialization is thought to aid in grasping and holding the female (Pearson et al. 2006), although in this instance it clearly is not serving that function, but I have not yet determined for what purpose the horizontal posturing of the front legs is all about (perhaps it is related to alarm behavior).

cicindela_scutellaris_habitat_p1020899_2We completed the day by documenting the occurrence of this species on the third of only three sizeable sand prairie relicts that remain on the Sikeston Sand Ridge – a private parcel located a few miles south of the other two preserves.  These observations have increased our confidence that C. scutellaris is secure in Missouri’s southeastern lowlands, and that – thankfully – no special conservation measures will be required at this time to assure its continued existence.  We also now have enough material on hand to characterize the range of variation exhibited by individuals across this population.  We hope this will allow a greater understanding of the relative influence of lecontei populations to the north versus unicolor populations to the south in contributing to the makeup of this population.

Since it was my birthday, it was appropriate that I should discover this “gift” next to the rim of my net after I slapped it over a mating pair of beetles.  I haven’t found a large number of Native American artifacts during my time in the field, but this has to be most impressive of those that I have found – it is in almost perfect condition, with only the smallest of chips off of one of the lower corners.  Edit 5/5/09: After a little research, I believe this to be a spear point from the Archaic period (12,000 to 2,500 years ago).

arrowhead_p1020900_2

p.s. – my 100th post!

REFERENCE:

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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Bon appétit!

/ Ted C. MacRae / 8 Comments

I collected this larva in northwest Nebraska during last year’s Fall Tiger Beetle Trip.  I collected an adult Cicindela lengi (blowout tiger beetle) at the spot – a species that greatly resembles but is much less common than the ubiquitous C. formosa (big sand tiger beetle – see my post Cicindela lengi vs. Cicindela formosa for a comparison of the two species).  Before finally finding that adult, however, I had fished out several larvae from the site in the hopes that they represented that uncommon species (see how I did this in my post Goin’ fishin’).  After collecting the larvae and placing them in a small terrarium with native sandy soil, they burrowed in but then closed up shop – I wasn’t sure whether they had survived or not.  In early December I put the terrarium in a 10°C incubator for the winter and brought it back out earlier this month.  Yesterday, happily, this larva and one other opened up their burrows again, so with any luck I’ll feed them well and they’ll complete their development.  While I do hope they represent C. lengi, other possibilities include C. scutellaris (festive tiger beetle), which would not be exciting, and C. nebraskana (prairie long-lipped tiger beetle), which would be VERY exciting.  One species I do not have to worry about it being is C. formosa, as the larvae of that species make very unique excavations in the sand with the burrow opening directed towards the excavation (I don’t believe I’ve posted photos of that here, yet – I’ll have to do so soon).

In the meantime, here is a closeup of the larva in the video prior to feeding. Those of you who have ever reared or photographed tiger beetle larvae will know just how easily “spooked” these larvae can be – any sudden movement will cause the larva to “drop” into its burrow and sit there for awhile. As a result, it was a real challenge to go through the whole process of taking first the photos and then the video while feeding it without causing it to drop.

cicindela_sp_larva_p1020936

Coming soon – lunchtime for adults!

Copyright © Ted C. MacRae 2009

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Coral Pink Sand Dunes tiger beetle – range map

/ Ted C. MacRae / Leave a comment

Those of you on RSS feed might be interested in revisiting my previous post, Coral Pink Sand Dunes tiger beetle on ARKive.  I’ve added a Google screen shot to the post that shows a visual perspective of the entire range of Cicindela albissima within a tiny inset of the state of Utah.  The image provides a sobering reminder of just how vanishingly small the range of this species is.  If we, as a society, cannot take the steps required to ensure the survival of a beautiful little species such as this one – living on only the tiniest sliver of the lands under our stewardship, it speaks ill of our ability to do so for other species with much greater habitat requirements.

Copyright © Ted C. MacRae 2009

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Coral Pink Sand Dunes tiger beetle on ARKive

/ Ted C. MacRae / 22 Comments

I’ve been meaning to write about ARKive for awhile now. ARKive is a unique collection of videos, images and fact-files assembled from among the world’s very best wildlife videographers and photographers in an attempt to create a centralized digital library of life on Earth. Their short to mid-term priority is the completion of audio-visual profiles for the 16,300-plus species on The IUCN Red List of Threatened Species, before moving on to profiling all species that have ever been filmed or photographed. With backing from many of the world’s leading conservation organizations, ARKive hopes to “promote public understanding and appreciation of the world’s biodiversity and the need for its conservation, through the power of wildlife imagery.”

With tiger beetle season almost now upon us, it seems appropriate to highlight the media collection that ARKive has assembled for one of North America’s most spectacularly beautiful and critically imperiled tiger beetles, Cicindela albissima (Coral Pink Sand Dune tiger beetle). This amazing species is not only stunning in appearance, with its nearly pure white elytra, but has perhaps the most restricted habitat of any tiger beetle species in North America – the entire population being restricted to 400 hectares within coral-pink-sand-dunes_3Utah’s Coral Pink Sand Dunes State Park and the adjacent Bureau of Land Management (BLM) dune management area (Pearson et al. 2006). The Google screen shot at right shows the entire range of this species as a light pink swath (inset shown on larger map of the state of Utah).  Regarded initially as a subspecies of the widespread C. limbata (sandy tiger beetle), recent molecular studies showed this beetle to be only distantly related to that species and, thus, deserving of full species status (Morgan et al. 2000).

Unfortunately, the beetle’s highly restricted habitat continues to be adversely affected by ongoing, recreational off-road vehicle use, especially in the interdunal swales used by the larvae. Impacts occur not only by direct run-over mortality, but also through disruption of normal adult and larval activity, damage to vegetation, reduction of arthropod prey of C. albissima, and mixing of the upper soil layer which increases desiccation of the larval microhabitat (Knisley and Hill 2001). The species was nominated for federal protection under the Endangered Species Act in 1996 (when it was still considered a subspecies of C. limbata), and two years later a Conservation Agreement between BLM, U.S. Fish and Wildlife Service, Utah Department of Parks and Recreation and Kane County was established in an effort to protect the critically sensitive habitats in which this species lives. Despite these conservation measures, ongoing monitoring and research within the protected areas has documented a continuing decline in the population, suggesting that these areas may not be of sufficient size to enable the population to increase, and off-road vehicle use continues outside of the protected areas (U.S. Department of Interior, Fish and Wildlife Service (FWS) 2008). While still only a candidate for federal listing as an endangered or threatened species, the FWS now considers the magnitude of the threat from off-road vehicles, in view of these recent findings, to be high and imminent. As a result, the FWS has increased the priority of the species’ candidacy from 8 to 2 (1 being the highest priority a candidate species can receive).

While I would dearly have loved to embed one of ARKive’s extraordinary videos or photographs of C. albissima within this post, copyright considerations do not allow that.  What I can do is provide hyperlinks directly to the site, and I encourage everyone to visit ARKive and see their images of this gorgeous species.

Photos by Christine Breton: adult beetle, dorsal view, adult beetle, adults mating, habitat

Videos by Ganglion Films: overview, adults mating, adult burrowing in sand, OHVs threatening protected habit.

In addition to the ARKive images, Chris Wirth, author of the blog Cicindela, has taken photographs of this species and presents stunning examples of both the larva and the adult in his post Cicindela albissima (Re-post). I myself am making plans to visit Coral Pink Sand Dunes – perhaps this season – to find and photograph this species for myself. When I succeed, rest assured those photographs will appear on this site.

REFERENCES:

Knisley, C. B., and J. M. Hill. 2001. Biology and conservation of the Coral Pink Sand Dunes tiger beetle, Cicindela limbata albissima Rumpp. Unpublished report.

Morgan, M., C. B. Knisley and A. Vogler. 2000. New taxonomic status of the endangered tiger beetle Cicindela limbata albissima (Coleoptera: Cicindelidae): evidence from mtDNA. Annals of the Entomological Society of America 93(5):1108-1115.

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.

U.S. Department of Interior, Fish and Wildlife Service. 2008. 50 CFR Part 17. Endangered and threatened wildlife and plants; review of native species that are candidates for listing as endangered or threatened; annual notice of findings on resubmitted petitions; annual description of progress on listing actions; proposed rule. Federal Register 73(238) (December 10, 2008):75176-75244.

Copyright © Ted C. MacRae 2009

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Tiger Beetle Safari

/ Ted C. MacRae / 24 Comments

In looking back at my posts over the past few weeks, I realized that it has been far too long since I’ve actually talked about beetles.  Perhaps “Petals In The Bush” would be a better name for this blog!  I still have some botanical thoughts to get off my chest before the insect season starts in earnest, but until then, and in anticipation of the upcoming summer’s hunts, I offer this fun, light-hearted introduction to collecting and keeping tiger beetles by Peter Schriemer.  Pay particular attention to the method he uses to capture these elusive little creatures:

Tiger Beetles are my favorite type of beetle! Entomologist John Acorn got me hooked on these little guys. They live across the country in various habitats, so you may not need to travel far to go on a Tiger Beetle Safari of your own!

Vodpod videos no longer available.

more about “Tiger Beetle Safari“, posted with vodpod

Capturing tiger beetle adults can a little (lot) more difficult than implied by this video. Adults have excellent eyesight, and many species are extremely wary. It takes practice, patience, and lots of second chances. The collecting method shown in the video is what I refer to as the “stalk and slap” method – the beetle is slowly stalked until within net reach, and the net bag is slapped over the beetle.  This method works well enough, but it has its limitations.  If there are any gaps between the ground and the net rim, the beetle will quickly dart through them and fly away.  This is easy to prevent on sandy and soft clay substrates, as the net rim can be sealed against the ground by kneeling quickly on each side of the rim to embed it slightly and using the hands to hold up the net bag and locate the beetle.  Still, there are a few things I don’t like about this method – the beetle may hide against the inside of the rim and be difficult to locate, and once found it may be difficult to grab the beetle through the net if it is against the ground (don’t even try lifting the rim and reaching under – the beetle will zip out and be gone).  This method can also be taxing on the legs, as each attempted capture involves kneeling and standing back up (getting harder and harder for these 50+ year old knees to do).

The major limitation of the slap method, however, is that it doesn’t really work on hard, uneven surfaces. Many species are found in glades and other habitats with exposed rock substrates. In these types of habitats, the net rim simply cannot be clamped tightly enough to eliminate the gaps (not to mention the added difficulties in kneeling on these surfaces).  Because of this, I have adopted a technique that I call the “tap and swipe” method.  Here again, the beetle is stalked until within net reach (made easier with a longer handle), but rather than slapping the net bag over the beetle, the rim of the net is tapped against the ground next to the beetle and then assertively swiped sideways to catch the beetle just as it starts flying.  A quick 180° flip of the net rim closes the opening to prevent the beetle from escaping, and it is easily seen in the hanging net bag, where it can be grabbed from outside the net bag with one hand to secure it before reaching into the net bag with the other hand.  With a little practice, one eventually learns to reach down into the open net bag and grab the beetle while preventing it from flying up and out.  All of this can be done while standing, so it’s easier on the knees.

The tap method does require more knowledge about the beetle’s escape behavior in order to anticipate how quickly and in which direction the beetle will fly – some species delay take off just slightly, thus requiring a slight “pause” between the tap and the swipe. However, once their behavior is learned I have found this method to be more consistently successful than the slap method – even on soft substrates.  For species that I haven’t encountered in the field before, I use the slap method at first (if I can) until I have a feel for their escape behavior. If I can’t, I use the tap method and hope for the best!

Copyright © Ted C. MacRae 2009

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Illinois Butterfly Monitoring Network

/ Ted C. MacRae / 6 Comments

For those of you who plan to be in the Chicago area on Saturday, March 7th, perhaps you’ll be interested in attending the 2009 Illinois Butterfly Monitoring Network Annual Indoor Workshop. I’ll be giving a talk entitled, “From Hilltops to Swamps: Insects in Missouri’s Rarest Prairies,” in which I’ll focus on the natural history and some associated insects in two of Missouri’s most critically imperiled natural communities – the loess hilltop prairies in the northwestern corner of the state, and the sand prairies of the southeastern lowlands. How a beetle guy ended up being invited to talk to a butterfly group is still a little confusing to me, but apparently IBMN Director, Doug Taron (author of Gossamer Tapestry) put in a good word for me.

The Illinois Butterfly Monitoring Network (IBMN) is a citizen scientist program monitoring the health of butterfly populations throughout northeastern and central Illinois.

The IBMN was initiated in 1987 by The Nature Conservancy to explore the effects of habitat management on invertebrates. From 7 sites in the Chicagoland area in its first year, the program has expanded greatly and is now monitoring more than 100 sites throughout Illinois.  Butterflies are ideal “indicator organisms” with which to monitor the effects of prescribed burning and other management techniques, since many species are restricted to intact prairie and savanna remnants by narrow habitat requirements.  The fact that they are relatively easy to identify allows them to be monitored in a cost effective manner with the help of dedicated amateurs.  Much the same can be said for tiger beetles (which will – surprise! – be featured prominently my talk).

The workshop will be held Saturday, March 7, 2009, 9:30 AM until 3:00 PM at the Gail Borden Public Library, 270 North Grove Avenue, Elgin (directions).  Registration is required, contact Mel Manner at (847) 464-4426 or by email.

Copyright © Ted C. MacRae 2009

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Top Ten of 2008

/ Ted C. MacRae / 10 Comments

For the first post of 2009, I begin with a look back at some of my favorite photos from 2008 (idea stolen from Alex Wild and others).  I initially hesitated to do a “best photos” post since I’m not really a photographer – just an entomologist with a camera.  Nevertheless, and with that caveat in mind, I offer ten photos that represent some of my favorites from this past year. To force some diversity in my picks, I’ve created “winning” categories (otherwise you might just see ten tiger beetles!). Click on the photos to see larger versions, and feel free to vote for your favorite. If so, what did you like about it? Was there a photo I didn’t pick that you liked better?  Enjoy!

Best tiger beetle

Cicindela formosa generosa

From “All the better to see you with, my dear!” (September 2008).  Picking a top tiger beetle photo was tough with so many to choose from.  Ultimately, I decided I really like these face-on shots, and of the several I’ve posted this one of Cicindela formosa generosa has the overall best composition, balance and symmetry.  I considered this one of Cicindela formosa formosa – with its half-cocked jaws, it probably has better personality.  However, the one above got the final nod because it is a true field shot of an unconfined, unmanipulated individual.

Best jewel beetle

Aegelia petelii

From Buppies in the bush(veld) (December 2008).  Although taken back in 1999, I just recently scanned and posted this photo of Agelia petelii from South Africa.  I like the bold, contrasting colors of the beetle combined with the soft colors of the host foliage.  Runners up included these photos of Evides pubiventris with its sumptuous iridescent green blending beautifully with the green background (but suffering slightly from shallow depth of field) and Chrysobothris femorata with its intricate surface sculpturing.

Best longhorned beetle

Tetraopes femoratus

From Rattled in the Black Hills (September 2008).  This was an easy choice – none of the other longhorned beetle photos that I posted during 2008 matched this photo of Tetraopes femoratus for clarity, composition, and the striking contrast between the red color of the beetle and the green color of the host plant.  I especially like the detailing of the body pubescence.

Best non-beetle insect

Proctacanthus milbertii

From Magnificently Monstrous Muscomorphs (November 2008).  I do like other insect besides beetles, and robber flies are hard to beat for their charisma.  This photo of Proctacanthus milbertii (which, as Chris Taylor pointed out, literally translates to “Milbert’s spiny butt”), has great composition and nice, complimentary colors.  I like contrast between the fine detail of the fly and the soft background.

Best non-insect arthropod

Argiope aurantia

From Happy Halloween! (October 2008). I didn’t have many non-insect arthropod photos to choose from, but this photo of a female Argiope aurantia (yellow garden spider) would be deserving of recognition no matter how many I had to choose from. I like the bold, contrasting colors and symmetry of the spider in front of the dappled background of this photo.

Best non-arthropod animal

Prairie rattlesnake (Crotolus viridis)

Another one from Rattled in the Black Hills (September 2008).  This is admittedly not the best photo from a purely technical perspective – it’s a little out of focus, and the color is a bit off.  However, no photo could better convey the moment – confronted with a live, angry prairie rattlesnake (Crotalus viridis) (among the more aggressive species in the genus).  The forked tongue and rattle – blurred in motion – were icing on the cake.

Best wildflower

Victoria Glades

From Glades of Jefferson County (July 2008).  I had several wildflower closeups to choose from, but I kept coming back to this field shot of pale purple coneflower (Echincea simulata) and Missouri evening primrose (Oenethera macrocarpa).  The eastern redcedars (Juniperus virginiana) in the background are at once indicative of their preferred habitat (limestone/dolomite glades) and also testament to their threatening encroachment.

Best tree

Calocedrus decurrens

From the very simply and aptly named Lake Tahoe, California (March 2008).  Incense cedar (Calocedrus decurrens), with its reddish, deeply furrowed bark and great height, is one of the most majestic of western conifers.  I was captivated by this tree – beautiful even in death and contrasting nicely with the surrounding green foliage.

Best rockscape

Pipestone National Monument, Old Stone Face

From Pipestone National Monument (April 2008).  “Old Stone Face” is one of Pipestone’s most recognizable geologic features, and the short angle of the sun on this early spring day provided nice detail to the cracks and fissures of the rock – almost appropriately adding a weathered “age” to this old man.

Best landscape

Emerald Isle, Lake Tahoe

Another one from Lake Tahoe, California (March 2008).  Few places on earth are more photogenic than Lake Tahoe, and this perspective overlooking Emerald Bay is among the finest views I’ve seen.  Brilliant blue skies and majestic snow covered mountains reflected perfectly from the still surface, with Fannette Island providing a perfect focal point for the photo.

Best miscellaneous

Water drops, Ozark Trail, Trace Creek SectionFrom Ozark Trail, lower Trace Creek Section (December 2007).  While technically not a 2008 photo, it’s close enough.  This was one of the first macro photographs I took with my camera, and it remains one of my favorites.  A chance occurence of an unlikely subject, created by cold temperatures and heavy moisture-laden air. I like the contrast between the water drops – sharp, round, and clear – with the vertical shapes of the leaf petioles and background trees.  Viewing the image full-sized reveals the reflection of the photographer in the leftmost water drop.

Subsequent edit: Okay, so after I put this post together, I realized I actually featured eleven photos – too much difficulty choosing, I guess. Let’s call it a baker’s ten.

Cicindela lengi vs. Cicindela formosa

/ Ted C. MacRae / 8 Comments

Back to beetle blogging – I hope everyone enjoyed their holiday break as much as I. One of the tiger beetles that I most hoped to see on my trip to Nebraska and South Dakota last September was Cicindela lengi (blowout tiger beetle). This is another one of the several tiger beetle species confined to dry sand habitats in the central/northern Great Plains (Pearson et al. 2006). Its common name would suggest it prefers sand blowouts, the most barren of dry sand habitats and where the co-occurring C. limbata (sandy tiger beetle) can be found. In reality, it also can be found in slightly more vegetated habitats such as dune margins, sand flats, and sandy roadsides along with the much more common C. formosa (big sand tiger beetle) and C. scutellaris (festive tiger beetle). It can also be found occasionally on sand bars along rivers, where the aptly-named C. lepida (ghost tiger beetle) is likely to occur, and in the northern part of its range it even inhabits boreal coniferous forest along sandy roadsides.

Cicindela lengi lengiDespite its relatively loose habitat requirements, C. lengi is not a common species. In Nebraska it may be locally abundant (Spomer et al. 2008), and while planning my trip I was fortunate to get a specific locality from Steve Spomer and Matt Brust for one of these localized populations in far northwestern Nebraska. [Happily, that locality was very close to the locality where I would be looking for another priority species for the trip, C. nebraskana (prairie long-lipped tiger beetle)]. The site – a sandy roadside embankment – was characterized by a very fine-grained sand, which Matt Brust tells me the species appears to favor over the coarser-grained sands more typical of the Sandhills to the east. Success did not come easily – when no adults were seen at the site after two consecutive days of searching, I hedged my bets and extracted larvae that I hoped would represent this species for an attempt at rearing them out to adulthood in the laboratory. Persistence paid off, however – a hunch told me to make one more visit to the site after a couple days in the Black Hills, with two adults (and another C. nebraskana!) being my reward.

The individual shown in the above photo was an unexpected surprise. It was captured a day later in the Sandhills proper at a locality where I expected to see not this species, but C. limbata (which I did succeed in finding at a nearby locality – see “Cicindela limbata – epilogue“). When I first saw this individual, I thought it was the ever present C. formosa (pictured below), which it greatly resembles and which, along with C. scutellaris, occurs commonly in suitable sand habitats throughout the Sandhills. Cicindela formosa formosaSomething about the way it flew gave me pause, however, and after capturing and looking closely at it in my hand I realized what it was. Cicindela lengi is distinguished from C. formosa morphologically by its slightly narrower form and longer, narrower labrum, but the quickest field identifier is the obliquely straight humeral marking (“C”-shaped in C. formosa). There are subtle behavioral differences also – both species are alert and quick to fly, but C. lengi lands quickly after a short flight, whereas C. formosa flies further and tends to land with a comical bounce and tumble or two across the sand. Cicindela lengi and C. formosa are not closely related despite their similar appearance – the former is assigned to subgenus Cicindela (Tribonia), while the latter is assigned to the nominate subgenus. The individual pictured above represents the nominate C. lengi lengi – populations north of Nebraska and Colorado exhibit a distinct coppery underside to the thorax and are assigned to subspecies C. lengi versuta, while populations in the southwestern part of its range show broadly coalesced elytral maculations and are assigned to subspecies C. lengi jordai.

REFERENCES:

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.

Spomer, S. M., M. L. Brust, D. C. Backlund and S. Weins. 2008. Tiger beetles of South Dakota & Nebraska. University of Nebraska-Lincoln Special Publication, 60 pp.