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

Back to some hard-core, field natural history.  Two years ago, on my virgin experience at collecting tiger beetles in Florida, I visited a spot called “Road to Nowhere”¹ at the suggestion of North American Tiger Beetle Master Dave Brzoska.  He said as many as 6–10 species can be seen there if the season is right, although my early August timing might be a tad late.  Despite having only a few hours from late afternoon to dusk to explore the area, I came close with the following five species: Cicindela trifasciata ascendens (Ascendent Tiger Beetle), Habroscelimorpha severa (Saltmarsh Tiger Beetle), Eunota togata togata (White-cloaked Tiger Beetle), Ellipsoptera marginata (Margined Tiger Beetle) and E. hamata lacerata (Gulf Beach Tiger Beetle) (see Tiger Beetles at Florida’s “Road to Nowhere”).

¹ For those of you who haven’t heard of the “Road to Nowhere,” it ranks as one of the top tiger beetle “hot spots” in the country (perhaps second only to Arizona’s famous Wilcox Playa).  According to Doug Taron at Gossamer Tapestry, the site—an expansive coastal salt marsh and mud flat along the isolated central Gulf Coast of Florida—was built some decades ago at the behest of corrupt state officials as a landing strip for small airplanes running drugs into this country.

One species I did not see on that trip is Habroscelimorpha striga (Elusive Tiger Beetle).  The common name is well deserved—the species is restricted to salt marshes, mud flats, and openings in coastal pine forest along the west and northeast coasts of Florida and South Carolina, and apparently nobody has ever seen it during the day (Pearson et al. 2006)!  Despite this, the Road to Nowhere is one place where the species can be seen somewhat reliably through its attraction to ultraviolet “blacklights.”  With this in mind, I began my 48-hour tiger beetle blitz during last August’s family vacation to Florida by timing my departure from St. Petersburg so that I arrived at the Road to Nowhere as dusk was falling—just in time to setup the lights, sit back with a beer, and wait for H. striga to cover the sheet!  The plan had a few kinks—I got a little bit of a late start, so by the time I got to Steinhatchee it was already getting dark.  Because of this, I missed one of the turns (my memory isn’t as good as it used to be) and got lost.  By the time I finally got my bearings, it was pitch black as I drove the 11-mile length of that lonely road through sand scrub and coastal marsh to a point where the road just simply stops.  Although the area is no longer used much for drug running, I still felt somewhat vulnerable as I setup the blacklight at the edge of the expansive salt mud flat.  There was one additional kink—I had forgotten to bring my copy of Pearson et al. (2006), any North American tiger beetle aficionado’s “Bible.”  Having only my memory of reading about the species to draw on, I hoped that I would recognize it if I saw it, or least recognize it as something different from the other species I expected to see there.

I’ve heard stories about the area being filled with tiger beetle collectors from all over the country with their blacklights and bucket traps, with someone yelling “striga!” every hour or so. However, I was the only person there that night. I hoped I wasn’t too late, as August is at the back end of the known adult activity period. Very quickly three other species, E. hamata lacerata, E. marginata and H. severa (the latter similar to H. striga, but much more abundant) began literally swarming all over the sheet and ground beneath. It was exciting at first, as I’d never encountered these (or any other tiger beetles) so abundantly at blacklights. In time, however, I satisfied my appetite for specimens and actually started becoming rather annoyed at their abundance—as if they might be “chasing away” the rare H. striga that was attracted to the light before I had a chance to see it.

Eventually, however, it happened. I spotted a somewhat different looking tiger beetle, but instead of yelling “striga!” my reaction was “What is that?” It was dark(ish), and I noted a subsutural row of green punctures on each elytron—”Is that punctulata?” I picked it up and looked at it closely, still thinking maybe punctulata but not sure. It was shinier, and a little bigger, and I noted the presence of marginal white spots at the middle and rear of the elytra. “No, that’s not punctulata… Is it striga? It must be striga! Yeah, it’s striga!” I dug down into the deep recesses of my memory and recalled that H. striga, indeed, was a darkish species, although I could not recall anything about the row of punctures. I finally decided that it really couldn’t be anything else but H. striga, an ID arrived at by process of elimination rather than recognition. Looking back, I feel a little cheated—I never got my “striga!” moment, that instant of sudden jubilation.  Instead, it was just a slow, creeping realization of what I had (listen to me—complaining about finding H. striga!).

I would actually find about a half dozen individuals of H. striga that night. The first one, per standard procedure, went live into a vial as a backup for studio photos if I didn’t manage to get any in the field.  That proved unnecessary, however, as I was able to photograph the two subsequent individuals shown in this post. It was not just H. striga that kept me busy with the camera, but feeding, perching, and trophy-bearing individuals of E. hamata lacerata and some other species that I have still to discuss as well. It was non-stop action from the time I setup the lights, interrupted only briefly at one point as I nervously watched a set of car headlights approach from the distance, stop a few hundred yards up the road, and then slowly turn around and disappear. By the time I finally took a moment to look at my watch it was already 1 a.m.! Soaking wet from the nighttime humidity, dirty from laying on the salty, muddy ground, and exhausted from the 4 hour drive and non-stop action after my arrival, I finally packed up the lights and began the drive back to civilization—praying that I would be able to find a motel without too much delay!

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