tiger beetles

St. Anthony Dune Tiger Beetle

/ Ted C. MacRae / 17 Comments

Sand dune habitat for Cicindela arenicola | vic. Idaho Falls, Idaho

After kicking off the 2011 fall tiger beetle trip by finding Cicindela formosa gibsoni and C. scutellaris yampae in the Yampa Valley sand dunes in northwestern Colorado, I was even more optimistic about my chances of seeing the main goals of the trip—the four C. maritima species group endemics that inhabit sand dunes in Idaho (St. Anthony Dune Tiger Beetle—C. arenicola, and Bruneau Dune Tiger Beetle—C. waynei), Utah (Coral Pink Sand Dune Tiger Beetle—C. albissima), and Colorado (Colorado Dune Tiger Beetle—C. theatina).  Each of these closely related species is restricted to a single sand dune system in their respective states, resulting in small populations that are especially vulnerable to drought and threats to their required habitats (primarily invasive plants and offroad recreational vehicles).  Cicindela arenicola, described from the St. Anthony Dune system of southeastern Idaho (Rumpp 1967) was our first target, and while the drive through the Snake River Valley—aspen and maple in blazing full color—was stunningly beautiful, all I could think about during the 6-hour drive was the rising temperatures outside and the tendency of these sand dune tiger beetles to dig in if it gets too hot.  I had information about several localities along the St. Anthony Dune system, and by the time we arrived at the first of these it was already early afternoon.

Cicindela arenicola adult burrows

Walking onto the dunes at a locality near Idaho Falls, it didn’t take long to find the unmistakable signature of adult activity—burrows.  Many insects (especially bees) and even non-insects (spiders, solifugids, etc.) that live on sand dunes create burrows that can look similar to those created by adult tiger beetles.  However, after years of experience I can almost tell at a glance whether a burrow has been created by a tiger beetle versus some other arthropod by the size and shape of the opening and appearance of the diggings.  When there is doubt, a little bit of excavating with a knife gives further clues in the shape of the tunnel—flatter than most other diggers and angling almost horizontally back into the sand before taking a dive a few inches back.  Wind quickly obliterates evidence of the burrow entrance and pile of diggings, so when these are present and fresh-looking the beetles have either just dug in or just dug out.  I excavated a number of burrows that turned out to be empty, suggesting the beetles were out and about if only I could find them.  And find them I did, mostly along the sloping, south-facing dune face above the flatter sand plain below.  They were as beautiful as I imagined they would be—bold, white markings, screaming green and copper highlights on the head and pronotum, and a dense covering of white hairs on the sides and undersurface.  They were also extremely active and wary, so much so that I didn’t even attempt to photograph them for the time being despite the decent number of individuals that we saw at the site.

Cicindela arenicola adult excavating burrow (click for better view of beetle just inside burrow entrance)

Cicindela arenicola in completed adult burrow | September 2011 | Idaho Falls, Idaho

There were other nearby sites that I had planned to check also, but with good numbers seen already and several other interesting insects (e.g., Crossidius spp.) found in abundance on the blooms of snakeweed plants growing on the backside of the dunes, there was really no reason to go anywhere else.  Besides, I still had not even attempted a field photograph of C. arenicola (although I had made sure to capture some live adults for studio shots that night as a backup).  As the sun began sinking in the western sky and temperatures began to cool off, I noticed the adults were becoming scarce and that fresh burrows were appearing on the dune surface.  In contrast to earlier in the day, adult beetles were found in nearly every burrow that I excavated—the beetles were digging in, and if I wanted field photographs it was now or never.  I managed a few distant shots of the first several adults I tried to stalk, but none of these were close to keepers.  I eventually noticed that beetles in the sparsely vegetated areas of the dune seemed to be slightly more approachable than those out on the open dune surface (perhaps they felt a little more secure in the presence of some cover), and although the vegetation often obscured clear views of the beetles, it was at least a more manageable problem than not even being able to approach them.  Finally, after considerable effort, I managed the photograph shown below.  I’d like to take credit for the near perfect composition and focus, but it was an actually a completely accidental shot.  I had been stalking the beetle for some time and had finally gotten closer to it than I had managed for any other beetle.  Rather than a presenting me with a lateral profile, the beetle was directly facing me as I closed in for the shot. Just as I pressed the shutter the beetle turned profile and then darted off.  Other than nipping the middle tarsus I don’t think I could’ve framed this uncropped photo better if I had tried.

Cicindela arenicola | September 2011 | vic. Idaho Falls, Idaho

Cicindela arenicola is closely related to C. waynei (known only from sand dunes in and around Bruneau Dunes State Park in southwestern Idaho), and it is only recently that the two have been considered separate species.  Cicindela waynei differs in its generally green rather than bronze coloration, more expanded white markings, and the presence of a curious upward projecting tooth on the male mandible (Pearson et al. 2006).  There are some populations in south-central Idaho assigned to C. arenicola that show an intergradation of characters between the two species, primarily in the presence of individuals with green coloration and expanded markings, so I found it interesting to encounter just such an individual at this southeastern Idaho site as well.  The individual, a male (and photographed in a terrarium that evening), looks very much like C. waynei except that it lacks the distinctive mandibular tooth characteristic of that species.

Male from same locality with green elytra and expanded markings

Cicindela arenicola is largely restricted to the Snake River Plain of southern Idaho, with a small population also occurring in the Centennial Sandhills of southwestern Montana (Winton et al. 2010). The sand dunes on which these beetles depend have suffered numerous assaults in recent years at the hands of man, with exotic invasives (Bouffard et al. 2009), trampling by cattle (Bauer 1991), and offroad vehicular traffic having the greatest impact on tiger beetle populations.  The species has been considered for listing on the Endangered Species List due to the imperiled nature of its limited habitat, but to this point such status has not yet been accorded.  It has, however, been listed as globally imperiled by the Idaho Department of Fish and Game and the Bureau of Land Management.  Most people are completely unaware that this beetle exists, and probably fewer still would even care.  For me personally, however, the chance to see this rare and beautiful beetle in its native habitat and spend time watching its behavior was a thrill I won’t soon forget.

Tiger beetle's-eye view of its preferred sand dune habitat.

I haven’t forgotten about the challenges that led to this post.  However, the hour is late and I need my rest.  Points will be awarded over the next day or so, and the winner of BitB Challenge Session #4 will be crowned!  In the meantime, I’ve released the submitted comments so you can see how your answers fared against the competition—no do-overs!

REFERENCES:

Bauer, K. L. 1991. Observations on the developmental biology of Cicindela arenicola Rumpp (Coleoptera: Cicindelidae). Great Basin Naturalist 51:226–235.

Bouffard, S. H., K. V. Tindall and K. Fothergill. 2009. Herbicide treatment to restore St. Anthony tiger beetle habitat: a pilot study. Cicindela 41(1):13–24.

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

Rumpp, N. L. 1967. A new species of Cicindela from Idaho (Coleoptera: Cicindelidae). Proceedings of the California Academy of Science 35:129–140.

Winton, R. C., M. G. Kippenhan and M. A. Ivie.  2010.  New state record for Cicindela arenicola Rumpp (Coleoptera: Carabidae: Cicindelinae) in southwestern Montana.  The Coleopterists Bulletin 64(1):43–44.

Copyright © Ted C. MacRae 2011

The Methocha

/ Ted C. MacRae / 5 Comments

As pointed out in my recent post, , there is much to learn still regarding tiger beetle larval parasitoids. In addition to bee flies (order Diptera, family Bombyliidae) of the genus Anthrax, tiphiid wasps (order Hymenoptera, family Tiphiidae) in the genus Methocha also parasitize tiger beetles in their larval burrows. Unlike bee flies, however, which sneakily lay their eggs in and around tiger beetle burrows when their victim isn’t watching, Methocha females aggressively engage the larva and even allow themselves to be grasped within the beetle larva’s sickle-shaped mandibles in order to gain entry to the beetle’s burrow.

Methocha appears to be a rather diverse genus, but it’s taxonomy is still incompletely known. George Waldren from Dallas, Texas is working on a revision of the genus and has found several new species in Texas alone. George is interested in seeing Methocha material from other areas as well and recently sent me the following reminder that adult females are active now:

…if you know of any areas with many tiger beetle larvae, now is the time to find Methocha. They superficially look like Pseudomyrmex ants, but once you see one you’ll catch on to them quickly. I collected more than 70 females today in a large aggregation of Tetracha carolina burrows.

In a subsequent message he adds:

Collect as many as you can, since they seem to be highly seasonal and rare most of the year. I almost always find them around beetle populations in sandy creek beds and receding bodies of water. A pooter works best if they are abundant and there isn’t much for them to hide under. Using your fingers also works—the sting is mild and usually doesn’t pierce the skin (depends on the person and size of the wasp). Vial collecting one by one works just as well.

Methocha females are generally overlooked due to their specialized life history and few specimens are in collections. Males are better represented since they’re easily collected with malaise traps.

If you have any Methocha specimens or manage to collect some, please contact George (contact info can be found at his BugGuide page). BugGuide does have a few photographs of these wasps to give you an idea of what they look like, but this excellent video titled “The Methocha” from Life in the Undergrowth with David Attenborough provides an unparalleled look at their appearance and behavior:


Copyright © Ted C. MacRae 2011

Cicindela scutellaris yampae – Yampa Festive Tiger Beetle

/ Ted C. MacRae / 6 Comments

In A Field Guide to the Tiger Beetles of the United States and Canada (Pearson et al. 2006), Cicindela scutellaris yampae (Yampa Festive Tiger Beetle) is one of 223 species and subspecies listed in the book’s index to species and subspecies. Although the book’s alphabetical listing places it second to last in the list, it surely must be considered near the top of any list based on beauty. It is also among the most geographically restricted tiger beetles in North America, restricted to the Maybell Sand Dunes in northwestern Colorado where it occurs with the equally beautiful, rare, and restricted Cicindela formosa gibsoni (Gibson’s Big Sand Tiger Beetle). Like that subspecies, C. s. yampae was one of six endemic sand dune tiger beetles targeted in this year’s Annual Fall Tiger Beetle Trip™, and as these photos show I was lucky enough to find it.

Cicindela scutellaris yampae | nr. Maybell, Colorado

As a species, C. scutellaris is one of North America’s most widely distributed and polytopic species, with the nominate and lecontei forms inhabiting a wide swath of the Great Plains and Midwest.  Around the eastern, southern, and western perimeters of its geographical distribution occur numerous named subspecies exhibiting a tremendous diversity of variations on the species’ “normal” coloration and maculation.  Cicindela s. yampae is most similar to the nominate subspecies due to its green head and prothorax with purple-red elytra, but it differs in possessing a broad white maculation on the side of each elytron (top photo).  There are individuals, however, in which the maculation is reduced to isolated spots (bottom photo), resembling somewhat the pattern of maculations seen in C. s. lecontei further to the east.

C. scutellaris yampae w/ reduced maculations

Pearson et al. (2006) note that records over the years suggest the remaining populations of this beetle are small. We did not see many individuals on our visit to the type locality east of Maybell early this past week (perhaps no more than seven total), and we saw none at a formerly larger sand dune about 10 miles west of Maybell.  In past years this latter site has supported good numbers of the beetle, but it has apparently succumbed to vegetational encroachment of the formerly more open sand dune. As far as I am aware there are no conservation measures in place on any level to protect these remaining populations and ensure that adequate suitable habitat remains to enhance the beetle’s long-term prospects.

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 2011

Cicindela formosa gibsoni… or not!

/ Ted C. MacRae / 11 Comments

Last Friday I began the 2011 Annual Fall Tiger Beetle Trip™. This year’s edition was actually a last-minute change—my original plans to collect wood for rearing wood-boring beetles in south Texas thwarted by that state’s long and continuing drought (along with the unwillingness of some of the area’s federal wildlife refuge managers to grant my research study permits despite the work I’ve done there in past years—apparently only institutional and not personal research is now deemed credible by these courageous individuals who are doing their best to protect the natural resources in their charge). My travel funds are limited, and rather than throw good money at a bad situation, I decided to pursue greater chances of success and make the trip that I have wanted to do for some time now—the Great Sand Dunes tour through the Rocky Mountains and Great Basin. The target species include many of the classic western sand dune species, and I hope to feature most of them in the days and weeks after the conclusion of the trip this coming weekend.

Cicindela formosa gibsoni | nr. Maybell, Colorado

The first of these target species that I encountered is the subject of this post, Cicindela formosa gibsoni (Gibson’s Big Sand Tiger Beetle).  This large, robust, and gorgeously marked subspecies is highly restricted in occurrence, curiously to two areas separated by more than 1,000 km—the Maybell Sand Dunes in northwestern Colorado (Moffat County) and the Great Sand Dunes of southwestern Saskatchewan.  It is distinguished from the nominate form and other subspecies by having the white markings of the elytra so expanded in most individuals that they coalesce and cover nearly the entire elytral surface.  The result of such a large white surface with contrasting red-purple head, thorax, and elytral sutural area is one of North America’s most spectacularly marked tiger beetle species.  The individual photographed here was one of many observed a few days ago on the Maybell Sand Dunes¹, and I feel truly lucky to have been able to personally witness these striking beetles flying powerfully across the dunes in their small home range, landing far away with the comical bounce and tumble that is characteristic of this and the other subspecies.

¹ In the interest of full disclosure, these photos were taken later in the day using subjects confined in a terrarium of native substrate. I had intended to photograph them in the field; however, they unexpectedly began digging burrows around 2 p.m., and my efforts to stalk the last few stragglers before they disappeared were not successful.


An interesting situation occurs regarding the taxonomy of this subspecies.  Despite the nearly identical appearance of adults from both the Saskatchewan and Colorado populations, logic and differences in larval coloration suggest that these two populations have arisen independently, their common appearance a result of convergence rather than shared ancestry.  Molecular studies are in progress to determine more conclusively whether this is true (hopefully augmented with material collected during this trip).  The subspecies was originally described based on specimens collected in Saskatchewan, thus, if convergence is confirmed the Maybell population will find itself needing a new name.

Congratulations to Doug Taron, who narrowly beat perennial heavyweight Ben Coulter, Tracy Mormon and Mr. Phidippus for the ID Challenge #12 win.  The overall standings remain unchanged, with Ben still in the lead with 65 points, Mr. Phidippus 2nd with 54 points, and Roy completing the podium at 39 points.  The final standings may seem like a lock, but there will still be one more challenge in the session—anything can happen!

Copyright © Ted C. MacRae 2011

A cicindelophilic wish list

/ Ted C. MacRae / 3 Comments

  • Cicindelia obsoleta vulturina disjuncts bolting across lichen-covered sandstone balds.
  • Cicindela scutellaris yampae—red, white and blue in all its glory!
  • Big, bold, hugely white Cicindela formosa gibsoni bouncing across the sand.
  • Cicindela arenicola dancing across the St. Anthony dunes.
  • Hugely-mandibled male Cicindela waynei riding the backs of their lovers.
  • The almost pure white Cicindela albissima in its own tiny little corner of Utah.
  • Cicindela theatina, perhaps most colorful of the western sand dune species.

In a perfect world, I will make it to every one of these locations and encounter each and every species in the list. More realistically, it would be presumptuous to expect complete success on such a quickly planned, last minute trip—I’ll be happy to make it to at least some of these sites and find what I’m looking for. Beyond the above species there should also be the more reliable Cicindela lengi, C. tranquebarica, and the nominate forms of C. formosa and C. scutellaris—classic denizons of the west. When I get a chance to take a look in alkaline flats, perhaps I’ll also be able to add C. willistoni or C. parowana to the bounty list. When I can take specimens, I will (responsibly), and when I can’t I’ll hopefully take acceptable photos. Really though, this is mostly about getting out and seeing a huge swath of the country that I’ve never seen before during the most gorgeous time of year. I’ll see it my way—up close and personal and not just blasting by at 70 mph. Sometimes life just doesn’t get any better!

Copyright © Ted C. MacRae 2011

Not all Florida tiger beetles are rare

/ Ted C. MacRae / 6 Comments

Tetracha carolina (Carolina Metallic Tiger Beetle) | Dixie Co., Florida

I fear my recent series of posts from Florida might leave readers with the impression that all of that state’s tiger beetle species are rare endemics occurring in tiny remnants of relictual habitats and encountered only by the most intrepid collectors enduring the harshest of conditions.  While it’s true that Florida has its share of such species (perhaps more than any other state in the country), it is also home to numerous species that most cicindelophiles would consider rather common—even pedestrian.  “Common” is a relative term, however, depending on where you live, and featured here is a species that until recently would have been for me just as exciting a find as Cicindelidia scabra or Habroscelimorpha striga.

Purple reflections and expanded apical lunules on the elytra distinguish this species from T. floridana

Tetracha carolina (Carolina Metallic Tiger Beetle) is one of the most widely distributed tiger beetle species in the Western Hemisphere, occurring not only across the southern U.S. but also the West Indies and south through Mexico, Central America, and the west coast of South America to Chile.  It was only during the past 10 years, however, that I actually saw the species for myself in Missouri, as it is restricted to the Mississippi Alluvial Plain in the extreme southeastern corner of the state (the so-called “Bootheel”).  Not much was known about the status of this species in Missouri the first time I encountered it under building lights at the University of Missouri Delta Research Center in Portageville.  It was my first experience with “nocturnal tiger beetling,” and you can imagine my excitement at seeing these green and purple beauties glittering in the light of my headlamp.  We now know that the species, despite its restricted occurrence in Missouri, is actually quite common in a variety of habitats in that part of the state, including even agricultural fields where they hide during the day under irrigation pipes (Fothergill et al. 2011).

I simply can't resist these tiger beetle face shots!

The individual in the photographs shown here was seen at the famed “Road to Nowhere” site in a remote part of the Florida Gulf Coast—one of eight total species of tiger beetles that I’ve seen at this site during my two August visits (2009 and this year).  This site is actually one of a few places in Florida where this species co-occurs with T. floridana (Florida Metallic Tiger Beetle), an endemic species restricted to estuarian habitats in the southern half of the Florida peninsula, and until recently considered a subspecies of T. carolina (Naviaux 2007).  The brilliant purple reflections in the basal half of the elytra clearly distinguish this individual as T. carolina, as did its occurrence up on the drier sandy roadside rather than down in the salty mud flats preferred by T. floridana.  Also seen at this site up along the road were numerous adults of the broadly distributed T. virginica (Virginia Metallic Tiger Beetle), making this one of the few sites in the country where three of the four U.S. species of Tetracha can be found (the fourth, T. impressa—Upland Metallic Tiger Beetle, is a Neotropical species that reaches the U.S. only in the Lower Rio Grande Valley of south Texas).

REFERENCE:

Fothergill, K., C. B. Cross, K. V. Tindall, T. C. MacRae and C. R. Brown. 2011. Tetracha carolina L. (Coleoptera: Carabidae: Cicindelitae) associated with polypipe irrigation systems in southeastern Missouri agricultural lands. Cicindela 43(3): in press.

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.

Copyright © Ted C. MacRae 2011

Two things I love about glades during fall…

/ Ted C. MacRae / 9 Comments

…prairie dock (Silphium terebinthinaceum) in bloom…

Prairie dock (Silphium terebinthinaceum) in bloom | Caney Mountain Cons. Area, Ozark Co., Missouri

…and prairie tiger beetles (Cicindelidia obsoleta vulturina) on the prowl…

Prairie tiger beetle (Cicindelidia obsoleta vulturina) | Caney Mountain Cons. Area, Ozark Co., Missouri

On the last weekend of August I made another trip to the White River Hills of north-central Arkansas in a last gasp effort to confirm the occurrence in the area of the swift tiger beetle (Cylindera celeripes).  Records of this species include a single individual collected in 1996 at a site near Calico Rock, but two trips to the area this past June had already failed to reveal its presence.  I didn’t really expect that I would find it this time either, and such was the case.  However, what I was expecting/hoping to see was the beginning of the fall emergence of the prairie tiger beetle.  The Missouri/Arkansas disjunct population of this handsome species is perhaps my favorite tiger beetle of all, not only because of its good looks but because of the many spectacular fall collecting trips I’ve taken through the White River Hills to look for it.  In this regard I had success, although only two individuals were seen all day long.  The area around Calico Rock seemed dry, apparently having been missed by the thunderstorms that rolled through the area a week earlier and that would have surely triggered full bore adult emergence. 

Long Bald Glade Natural Area, Caney Mountain Cons. Area, Ozark Co., Missouri

The following day I returned to Caney Mountain Conservation Area on the Missouri side, where last fall I had finally found prairie tiger beetles after years of searching what must be the extreme northeasternmost limit of its distribution.  Fresh evidence of recent rains was seen, and accordingly the beetles were out in fairly decent numbers in the same area where I found them last fall.  I took the opportunity to photograph a few individuals (which I had not done last year) and then turned my attention to looking for other insects.  I had my eye out for the spectacularly beautiful bumelia borer (Plinthocoelium suaveolens) and eventually found one.  I hoped also to see the marvelously monstrous Microstylum morosum (North America’s largest robber fly), which I found at this site in 2009 as a new state record and was rewarded with two individuals (these will serve as vouchers for the state record, since I didn’t collect it in 2009).  Temperatures were rather warm and both of these latter species are traditional “summer” species; however, the presence of prairie tiger beetles, the tawny tinge to the prairie grasses, and the noticeably longer shadows under a deep blue sky told me that fall was, indeed, on the way.

Prairie tiger beetle (Cicindelidia obsoleta vulturina) | Caney Mountain Cons. Area, Ozark Co., Missouri

While prairie tiger beetles are (at least for me) the most iconic harbinger of fall in the White River Hills, another classic fall sight was the thick stands of prairie dock plants with their tall, bolting flower spikes.  In Missouri this plant serves as a larval host for the longhorned beetle Ataxia hubbardi.  In my early years of collecting in Missouri’s glades, I delighted in finding adults of these beetles clinging to the flower stalks during fall—presumably laying eggs from which larvae would hatch and bore down into the tap-root.  Although commonly regarded as a pest in sunflower in the southern Great Plains, individuals associated with prairie dock in Missouri’s glades seem different—smaller, narrower, and darker—than those found on sunflower and other more common hosts.  Additional material will be needed to make a final assessment on whether these individuals represent a distinct taxon; however, I have not been able to find this species on prairie dock in Missouri since I moved back to the state nearly 16 years ago.  The reason for this sudden disappearance remains a mystery, and perhaps it is purely coincidental that the Missouri Department of Conservation began managing all of their glades with prescribed burns during my previous 5-year absence from the state.  In the meantime, I will continue to examine prairie dock stems every fall in the hopes that once again I will find the beetles and be able to come to a decision about their taxonomic status.  Perhaps I should re-focus my efforts in “low quality” (i.e., never-burned) gladey roadsides rather than our state’s “high quality” (i.e., high floral diversity) natural areas.

Copyright © Ted C. MacRae 2011

Mini-review of the Cicindelidia abdominalis species-group

/ Ted C. MacRae / 8 Comments

Now that I have seen and photographed in the field all four species of the Cicindelidia abdominalis species-group, I thought some might find it useful to have a summary of each species with comparisons, photographs and a key to distinguish the four species. The key presented below is based on that found in Brzoska et al. (2011), which itself is a modification of couplet 8 in the key to the species of Common Tiger Beetles (Cicindela) found in Pearson et al. (2006). Following the key are comparative notes for each species that discuss key characters and give specific information about their distribution, along with field photographs to illustrate the distinguishing characters.

Key to the Cicindelidia abdominalis species-group

1. Elytral surface covered with deep punctures, pronotum with dense decumbent setae (old specimens may have the setae rubbed off and the presence of setal punctures should be checked), usually with 6 labral setae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

— Elytral surface (excluding presutural foveae) relatively smooth, with shallow punctures, pronotum glabrous or with fine pronotal setae, usually with 4 pronotal setae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2(1) Elytra black, with a post median marginal spot, usually with a vestige of a middle band, restricted to peninsular FL north of Miami-Dade County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C. scabrosa (Schaupp)

— Elytra green or bronze-green, rarely with a post median marginal spot, and without evidence of a middle band, restricted to Miami-Dade County, FL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C. floridana (Cartwright)

3(1) Pronotum, and mes- and metepisternum glabrous, restricted to Polk and Highlands Counties, FL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C. highlandensis (Choate)

— Pronotum with fine decumbent setae, and mes- and metepisternum with decumbent setae, widespread across southeastern U.S. Coastal Plain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C . abdominalis (Fabricius)

Cicindelidia scabrosa—Scabrous Tiger Beetle

This species is largely limited to oak/pine scrub habitats in peninsular Florida north of Miami-Dade Co., although it does just sneak north of the border into souutheastern Georgia. From Cicindelidia abdominalis and C. highlandensis it can be distinguished by the distinctly punctured rather than smooth elytra and the presence of dense white setae along the lateral margins of the pronotum. From C. floridana it can be distinguished by the black rather than coppery-green coloration and the usual presence of a post-median spot along the lateral elytral margins. More information about this species can be found in my post, “The (almost) Florida-endemic Cicindelidia scabrosa.”

Cicindelidia scabrosa
Cicindelidia scabrosa | Levy Co., Florida

Cicindelidia floridana—Miami Tiger Beetle

Only recently rediscovered after being thought extinct for nearly a century, this species is most similar to C. scabrosa but is restricted to pine rockland habitat in Miami-Dade Co. where C. scabrosa does not occur. Like that species it exhibits the distinctly punctured rather than smooth elytra and dense white setae along the lateral margins of the pronotum that distinguish both species from C. abdominalis and C. highlandensis; however, its coloration is brilliant coppery green rather than black like C. scabrosa, especially in living individuals seen in the wild. More information about this species can be found in my posts, “Rediscovery of Cicindela scabrosa floridana” and “Photographing the Newly Rediscovered Cicindelidia floridana.”

Cicindelidia floridana
Cicindelidia floridana | Miami-Dade Co., Florida

Cicindelidia highlandensis—Highlands Tiger Beetle

This species is most similar to C. abdominalis, sharing with it the smooth elytra and glabrous pronotum that distinguish both species from C. scabrosa and C. floridana. Unlike that more widespread species, however, C. highlandensis is found only along a narrow band of sand scrub habitats on the Lake Wales Ridge in Polk and Highland Cos., central Florida, and it can be distinguished from it by the lack of white setae on the pronotum and mes- and metepisterna (lateral portions of the thorax above the middle and hind legs). More information about this species can be found in my post, “Highlands Tiger Beetle.”

Cicindelidia highlandensis
Cicindelidia highlandensis | Polk Co., Florida

Cicindelidia abdominalis—Eastern Pine Barrens Tiger Beetle

This is the only relatively broadly distributed species of the group, occurring in a variety of dry sand habitats along the southeastern U.S. Coastal Plain from New Jersey west to Louisiana and south into the northern half of Florida. Aside from its non-endemic distribution, this species can be distinguished from C. scabrosa and C. floridana by its smooth elytra and lack of dense white setae along the lateral pronotal margin, and from it’s most similar relative C. highlandensis by the presence of fine, decumbent (lying down) setae on the pronotum and on the mes- and metepisterna above the middle and hind legs. More information about this species can be found in my post, “Tiger Beetles Agree—It’s Hot in Florida!.”

Cicindelidia abdominalis
Cicindelidia abdominalis | Withlacoochee Co., Florida

REFERENCES:

Brzoska, D., C. B. Knisley, and J. Slotten. 2011. Rediscovery of Cicindela scabrosa floridana Cartwright (Coleoptera: Cicindelidae) and its elevation to species level. Insecta Mundi 0162:1–7.

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 2011