endemic species

Revisiting the Highlands tiger beetle (Cicindelidia highlandensis)

/ Ted C. MacRae / 12 Comments

In September 2016, I had the opportunity to attend the Annual Meeting of the Entomological Society of America in Orlando, Florida, which was being held in conjunction with the International Congress of Entomology. My first thought when I made plans to attend these meetings was that this would be a chance for me to get another look at the Highlands tiger beetle (Cicindelidia highlandensis). One of Florida’s rarest endemic tiger beetles, this species is restricted entirely to remnant sand scrub and pine woodland habitats along the Lake Wales Ridge of Polk and Highlands Counties in central Florida (Choate 2003). I was thrilled to have found adults (in good numbers) on my first attempt back in 2009, and I was also thrilled to have successfully managed to photograph the beetle at that time. However, in the years since, I have become increasingly dissatisfied with those photographs—taken during what was my very first year of insect macrophotography. I’ve learned a lot since then about lighting, diffusion, and composition, but perhaps the biggest annoyance of those photographs is the fact that in every one the antennae and/or legs are “clipped”—a result of my being so enamored with my newfound macrophotographic capabilities that I nearly completely ignored other aspects of photographic composition.

Chris Brown photographing Cicindelidia highlandensis

Chris Brown photographs a Highlands tiger beetle.

Chris Brown—long-time field accomplice and himself a tiger beetle aficionado and insect macrophotographer—was also at the meetings, and since he had never seen the Highlands tiger beetle before we made plans to slip away one day and visit the spot where I had seen them back in 2009. I knew our chances of finding them were slim—it was very late in the season (late September), and the species is a so-called “summer species” with peak of adult activity in July and August. We figured, however, that even if we didn’t find adults we would still enjoy the day in the field, and for some time after arriving at the site that’s all it was. Finally, in an open sandy area near a small lake we saw the first adult. I let Chris take his shots, as this was his first opportunity (see photo above), while I continued to search for additional adults. Eventually I found one and began the long process of “whispering” to it to coax it into allowing me the photographs I desired.

Cicindelidia highlandensis

Highlands tiger beetle (Cicindelidia highlandensis).

As you can see in the photograph above, my compositional preferences have changed since I took those first photographs back in 2009. In contrast to the “as close as possible” style that I initially adopted, I now prefer to back off from the beetle enough to include elements of the habitat in which it occurs. While this compositional style may show less detail on the beetle itself, I believe it adds perspective and results in a more interesting and aesthetically pleasing photograph. I also now like to get down as low as I can, often placing the camera directly on the ground rather than always shooting from “elbow-height”, for a more unique perspective of the beetle, and my use of better flash diffusion results in more even lighting and minimizes the distracting specular highlights that are often the hallmark of flash macrophotography.

Cicindelidia highlandensis

This individual demonstrates the thermoregulatory “stilting” behavior of the adults.

Sadly, my flash unit failed soon after I began photographing the beetle, which is a real shame because the beetle began demonstrating the characteristic “stilting” behavior that the adults use for thermoregulation in their hot environment. The photograph above is the only one that I could “rescue” through some rather heavy-handed post-processing to make up for the failure of the flash unit to fire (it is fortunate that I have shifted to routinely using a combination of ambient light and fill-flash rather than flash only, or I would have had not even this photograph to rescue!). I suppose this means I’ll just have to revisit this species once again (now that I have not one but two new flash units!), which isn’t all bad because I would also love to see and photograph once again the moustached tiger beetle (Ellipsoptera hirtilabris), another Florida endemic (or near so) that I saw here also during my first visit but not during this one.

The Highlands tiger beetle belongs to a group of species called the abdominalis species-group, with all four of the included species (C. abdominalis, C. floridana, C. highlandensis, C. scabrosa) occurring in Florida (three of which are endemic or near-endemic to Florida). For those interested, I have seen and photographed all four of the species and presented a “mini-review” with photographs and links to posts with more detailed information about each species, along with a key to the species to allow for their identification.

REFERENCES:

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.

© Ted C. MacRae 2019

Two endemic Jamaican jewel beetles: one known, one not?

/ Ted C. MacRae / 1 Comment

I recently received a batch of jewel beetles from Enrico Ruzzier of Italy. It was an impressive sending (as is any sending of jewel beetles!) collected from diverse parts of the world, but what really caught my eye were two specimens he had collected earlier this year in Jamaica—both representing species in the genus Chrysobothris. Most members of this genus are moderate-sized in relation to other species in the family, but at only 5 and 6 mm in length the two specimens I received are downright tiny. They also are extraordinarily pretty compared to most species in the genus by virtue of their striking patterns of metallic green, red, and blue to violaceous colors! Even more interesting, however, was their West Indian provenance. This “biodiversity hotspot” enjoys not only high species diversity but also high species endemism as a result of the 7,000+ islands that comprise it. This is especially true for Jamaica, where my records indicate that 64% of the known jewel beetle fauna (16 of 25 species) occurs nowhere else.

One of the specimens was easily identifiable as Chrysobothris quadrimaculata (Fabricius, 1776) because of the transverse green, violaceous, and reddish-cupreous bands on the pronotum and metallic green “cross” on the elytra separating four large violaceous spots, each with a reddish-cupreous central area (Fisher 1925). This species has so far been found only in Jamaica and appears to be uncommon in collections. As far as I can tell, the only illustration of the species is a 224-year old drawing appearing in Olivier (1790)¹. Considering this and the extraordinary beauty of this little beetle, it seems appropriate to post a photo here (sent to me by Enrico in his initial query regarding its identity).

¹ This early landmark taxonomic publication is occasionally offered for sale by rare book dealers at asking prices that run in the thousands of dollars! Fortunately, the National Library of France has made a pdf of the book available for free download.

Chrysobothris quadrimaculata (Fabricius, 1776)

Chrysobothris quadrimaculata (Fabricius, 1776). Photo by Enrico Ruzzier.

The second specimen, even smaller but no less pretty than the first, has defied all attempts at identification. It does not key out in Fisher (1925) and clearly differs from the four species and one subspecies known to occur in Jamaica (all of which are endemic). Further comparison with descriptions of all known West Indian species also fails to turn up a match. Considering this and the fact that many West Indian Chrysobothris seem to be quite rare in general (Maier & Ivie 2012), I would not be surprised if this specimen turns out to represent yet another (and as yet undescribed) endemic species for Jamaica. I am hopeful (although not optimistic) that posting a photo here (also provided by Enrico Ruzzier) will prompt those with West Indian material in their collections to examine their holdings and see if any additional specimens can be located.

Chrysobothris n. sp. ex Jamaica

Chrysobothris n. sp.? Photo by Enrico Ruzzier.

REFERENCES:

Fisher, W. S. 1925. A revision of the West Indian Coleoptera of the family Buprestidae. Proceedings of The United States National Museum 65:1–207 [BioDiversity Heritage Library, BioStor].

Maier, C. A. & M. A. Ivie. 2013. New species and records of Chrysobothris Eschscholtz (Coleoptera: Buprestidae) from Montserrat, Saba, and Anguilla, with a key to the Chrysobothris thoracica species-group in the West Indies. The Coleopterists Bulletin 67(2):81–88 [BioOne].

Olivier, A. G. 1790. Entomologie, ou histoire naturelle des insectes, avec leurs caractères génériques et spécifiques, leur description, leur synonymie, et leur figure enluminée. Coléoptères. Tome 2, genera 9–34 (32. Bupreste), pp. 1–485, 63 plates, Baudouin, Paris [Bibliothèque nationale de France].

© Ted C. MacRae 2014

Colorado’s Great Sand Dunes Tiger Beetle

/ Ted C. MacRae / 19 Comments

Great Sand Dunes National Park | Saguache and Alamosa Counties, Colorado (click for 1680 x 887 version)

Last year’s Annual Fall Tiger Beetle Trip entered its last day as an unqualified success. Travel partner Jeff Huether and I were doing the “Great Western Sand Dune Tour” on a quest to find and photograph some of North America’s most geographically restricted tiger beetles. The first four days featured successful visits to northwestern Colorado’s Maybell Sand Dunes for Cicindela scutellaris yampae and Cicindela formosa gibsoni, southeastern Idaho’s St. Anthony Sand Dunes for Cicindela arenicola, and southwestern Utah’s Coral Pink Sand Dunes for the prize of the trip—Cicindela albissima. The only endemic that we had failed to find was Cicindela waynei at southwestern Idaho’s Bruneau Sand Dunes (hopefully this was a result of poor fall emergence conditions rather than an indication of further decline of this perilously endangered species).

Small sand dune west of GSDNP in the Nature Conservancy's Medano-Zapata Ranch.

Day 5 featured a visit to southwestern Colorado’s Great Sand Dunes to look for the endemic Cicindela theatina. As on every day previous of the trip, the morning drive saw cool but rising temperatures under bright, sunny skies, so we were optimistic about our chances. Between Great Sand Dunes National Park (type locality of the beetle) and The Nature Conservancy’s Medano-Zapata Ranch west of the park, the entire 290 km² range of C. theatina is on protected land. Not knowing whether the beetle would be out and, if so, how extensively it would occur, our plan was to approach the Park from the west through Zapata Ranch and stop at any sand dunes we sighted along the way until we found the beetle.  It didn’t take long—as soon as we entered the Ranch we began to see small sand dunes in the distance, and within minutes after making the 1-km hike towards one particularly promising looking dune we saw the beetles. Even though this was the fifth western sand dune endemic I had seen in as many days, the first moment I laid eyes upon it was no less exciting—flashing red and green on coppery, white marked elytra, it seemed all hair and teeth!

Great Sand Dunes tiger beetle (Cicindela theatina) | Medano-Zapata Ranch

Despite this being my first sighting of the species, there was no doubt about it’s identity. The only other tiger beetle that occurs with and could possibly be mistaken for C. theatina is the blowout tiger beetle, C. lengi; however, the broad marginal band that runs completely around the elytra and the green/brown dorsal coloration of C. theatina are enough to distinguish it from that species. Temperatures were still a bit on the cool side, but the beetles were already remarkably active and skittish. Like the other sand dune species we had already seen, they were enormously difficult to approach—numerous failed attempts were necessary before I encountered the slightly more cooperative female shown in these photos (although she still required several minutes of stalking to get her sufficiently accustomed to my presence to allow these shots).

Like most sand dune tiger beetles, adults are densely hairy on the lateral and ventral surfaces.

Adults ''hug'' the sand for warmth during the cooler morning hours.

The dense covering of white hairs on the lateral and ventral surfaces of the adults belies their adaptation to the abrading sands of their wind-swept habitat. Scouring sands, however, are not the only hardships that the adults must contend with. Temperatures on the dunes can range from as low as 40° F on a chilly morning to nearly 140° F during the heat of the day. Accordingly, much of the adult beetle’s activities revolve around thermoregulation to maintain optimal body temperatures for activity (Pineda and Kondratieff 2003). These include not only stilting, shade-seeking, and mid-day burrowing to avoid excessive warming (see my post  for examples of these behaviors), but basking to gain warmth when temperatures are still a bit too cool for effective foraging (photo above).

Fabulous metallic red and green highlights on the head and pronotum contrast with the reddish brown elytra and their white lateral markings.

Despite the fact that the entire range of this species is encompassed by protected land, WildEarth Guardians filed a petition for federal listing as an endangered species in 2007 (Tweit 2010). Whether protection will be granted remains to be seen—Coral Pink’s C. albissima has a global range only 1.3% the size of C. theatina‘s range (only slightly more than half of which is on protected land), yet that species has been awaiting listing for nearly three decades now! (Too bad C. theatina doesn’t have real fur, feathers, or those endearing mammalian eyes that would surely allow it to jump to the front of the line.)

For the first time in BitB Challenge history, we have a 4-way tie for the win. Dorian Patkus, Mr. Phidippus, Mike Baker, and David Winter all share the honors for . Mr. Phidippus is the big winner, however, as he strengthens his grip on the overall lead with a lead of 13 or more points over his nearest rivals (Roy, Tim Eisele, Mike Baker, and Dennis Haines). The competition is far from over though—a single misstep is all it would take to see the emergence of a new leader before this session is over.

REFERENCES:

Pineda P. M. and B. C. Kondratieff. 2003. Natural history of the Colorado Great Sand Dunes tiger beetle, Cicindela theatina Rotger. Transactions of the American Entomological Society 129(3/4):333–360.

Tweit, S. J. 2010. Beetle Mania. National Parks 84(4):24–25.

Copyright © Ted C. MacRae 2012

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

Why I Roamed the Marsh at Night

/ Ted C. MacRae / 22 Comments

Tetracha floridana (Florida Metallic Tiger Beetle) | Pinellas Co., Florida

For two years I waited.  The narrow strip of coastal scrub and mangrove marsh along the intracoastal waterway behind my sister-in-law’s condominium in Seminole, Florida had been an unexpected surprise during my first visit in August 2009.  Despite its small size and urban surroundings, it proved to be a good spot for tiger beetles, including Ellipsoptera marginata (Margined Tiger Beetle) and the closely related E. hamata lacerata (Gulf Coast Tiger Beetle).  Also living there was a much rarer tiger beetle—the Florida-endemic species Tetracha floridana (Florida Metallic Tiger Beetle), but I did not know this at the time.  In fact, had I not happened upon some larval burrows as I was leaving the preserve and decided to collect a few and rear them to adults, I would still not know they were there.  Only after the two larvae that made it back to St. Louis alive emerged as adults in their rearing container did I realize what I had found.  The reason I had not seen any adults during my visit was simple—they, like all members of the genus to which they belong, are strictly nocturnal!  Nevertheless, I knew I would return sooner or later and have another shot at seeing adults of this species in the wild.

A male, distinguishable by the thick brushy pads on the front tarsi.

And return I did.  My wife and I decided fairly early this year that we wanted to return to Florida for our summer vacation.  She likes the beach and her sister, and the kids like the beach and their aunt.  I don’t like the beach so much (though my sister-in-law is pretty cool), but I love Florida for its diversity of tiger beetle species and their high level of endemism.  During my 2009 trip I managed to find nine species, which, in addition to T. floridana, included also the very rare and potentially threatened Cicindelidia highlandensis (Highlands Tiger Beetle), known only from the Lake Wales Ridge in central Florida, and the (near) endemic Ellipsoptera hirtilabris (Moustached Tiger Beetle).  This year I set my sight on several other endemics—e.g. Cicindelidia floridana (Miami Tiger Beetle)—and near-endemics—e.g. Cicindelidia scabrosa (Scabrous Tiger Beetle).  My searches for these targets would have to wait for a few days, but for T. floridana I had only to wait until nightfall on the day we arrived.  The bleating chorus of tree frogs was my signal, and as the rest of the family retired to their bedrooms I geared up with my collecting fanny pack, camera bag and headlamp and headed out to the marsh.

The species lacks the violaceous reflections found on the elytra of T. carolina.

As I mentioned in my previous post, it was a little unnerving to walk into the marsh surrounded by darkness and greeted by scuttling hordes of sea slaters.  The anticipation of finally seeing T. floridana, however, was more than enough motivation to forge onward while deliberately scanning the ground with my headlamp.  For some amount of time I focused on the more barren areas, which is where I would have expected the adults to occur, but only after I also began scanning some of the sparsely vegetated ground—typically slightly elevated above the moister and more barren areas—did I see the first adult.  Its agile dash into and through the vegetation upon my approach was a little surprising and required more effort than I expected to finally capture it.  Elation!  Finding rare species is always a treat, but it is extra special when you find one where nobody previously knew it existed.  Over the course of the next 1½ hours (as well as the following night and two nights after that) I would see countless adults, giving me comfort that I could collect a reasonable voucher series without causing negative impacts on the population.

A female oviposits in the soil amongst the sparse, salt-tolerant vegetation.

I had hoped to see mating pairs but never did; however, I did find a female in the act of oviposition.  Consistent with the apparent adult preference for sparsely vegetated areas rather than barren ground, the female was nestled amongst the vegetation while she excavated a hole for the egg she would lay.  On the last night that I visited the marsh, I focused my efforts on finding larval burrows, starting in the area where I had seen them two years ago.  I only found a few but succeeded in fishing one 3rd-instar larva out of its burrow.  You see, even though I photographed one two years ago, the larva of this species remains undescribed in the literature.  Since I allowed the two larvae I had collected to complete their development to adulthood, I still lacked preserved specimens that could be used for the basis of a description.  I now had one, but for a formal description it would be better to have at least a few examples.  Remembering that I had seen the female ovipositing amongst vegetation rather than out in the open, I began searching the nearby vegetated areas for burrows.  This approach was met with better success, and from the dozen or so burrows that I was able to find, I succeeded in fishing out two more 3rd-instars.  I already have several preserved larvae of Tetracha virginica (Virginia Metallic Tiger Beetle) and a single T. carolina (Carolina Metallic Tiger Beetle) collected in southeastern Missouri by my good friend Kent Fothergill—this small series of T. floridana now leaves me lacking only the also-undescribed T. impressa (Upland Metallic Tiger Beetle) among the four North American (sensu stricto) species of Tetracha.  I will be anxious to compare the larvae of T. floridana I now have with those of T. carolina and T. virginica in an effort to find species-specific characters.

This male is sporting some very impressive teeth on his mandibles.

Copyright © Ted C. MacRae 2011