Big, Bold, and Beautiful

Cicindela formosa generosa | Castlewood State Park, Missouri.

Last fall I took my younger daughter to the Al Foster Trail on the western side of Castlewood State Park, just a few miles down the road from my house.  As we walked the trail through typical bottomland forest next to the Meramec River, I noticed what appeared to be open ground on a rise to the north of the trail.  When I went up to investigate, I saw a rare sight for Missouri—dry sand!  Obviously a deposit from some past flood event, the post oaks established around its perimeter and native warm season grasses sparsely dotting its interior suggested it had been laid down many years ago.  Such sights were likely common along the big river systems of pre-settlement Missouri, as natural flooding cycles laid sand deposits up and down the river courses, each deposit gradually succumbing to vegetation as new deposits were laid down elsewhere.  Today, with channelization and levees for flood control, the Missouri and Mississippi Rivers are just narrow, hemmed-in shadows of their former selves, unable to lay down such deposits in most years until, at last, catastrophic flooding occurs on a grand scale (as is occurring now).  Feeding into the Mississippi River just south of the Missouri River is the Meramec River—as the state’s only still-undamned undammed river system, it still has opportunity on occasion to lay down these interesting dry sand habitats.

The dark brown coloration of this rather ''dirty'' individual is typical of most Missouri populations.

When I see dry sand habitats in Missouri, three tiger beetle species immediately come to mind—Cicindela formosa (big sand tiger beetle), C. scutellaris (festive tiger beetle), and Ellipsoptera lepida (ghost tiger beetle).  My colleague and co-cicindelophile Chris Brown and I have spent many a weekend traveling up and down the state’s river systems with these species in mind.  None of them are rare in the state, but their fidelity to deep, dry sand habitats also makes them by no means common.  It is always cause for celebration when a new site is discovered for one of these species somewhere in Missouri.  Thus, it was in anticipation of one (or more) of these species that I returned to the spot last week on the first truly gorgeous spring day of the season.  Could it really be that, after ten years of searching for these species throughout the state, I would find a population just a few miles down the road from my house?!

A number of individuals in this population show traces of the bright coppery red coloration more typical of nominotypical populations west of Missouri.

Walking onto the site, I began to see tiger beetles immediately.  However, they were Cicindela tranquebarica (oblique-lined tiger beetle), a common species in Missouri that enjoys not only dry sand habitats, but also wet sand, wet mud, dry clay, and even concrete habitats—hard to get excited about such a habitat slut!  Nevertheless, within minutes I began seeing more robust beetles that were unmistakably big sand tigers.  Big, bold, and beautiful, the beetles were wary in the late afternoon heat and quickly launched into their powerful escape flights that ended comically some 20 yards away with a characteristic bounce and a tumble.  Such behavior might seem to make them impossible to photograph, but I’ve been at this for awhile and know their behavior pretty well—a slow, cautious approach, crouching carefully at the right distance, and crawling deliberately on elbows and knees while peering from behind the camera until it shows up in the lens set to 1:3 (one-third life size).  Then it’s a matter of even more slowly closing the distance and scooting around to get the desired angles and composition.  Move slowly enough and they’ll forget you’re there and resume normal behavior—you’ll be richly rewarded with views of foraging, stilting, and other classic tiger beetle behaviors.

Coloration and markings may seem conspicuous but provide excellent camouflage against the pebbley-sand substrate.

Most of the big sand tiger beetle populations we have found in Missouri are typical of the eastern subspecies C. formosa generosa, distinguished from other named subspecies by the dark brown dorsal coloration and thick white markings that are separate dorsally and joined along the outer edges of the elytra (Pearson et al. 2006).  This subspecies is predominantly midwestern and northeastern in distribution, while the typically bright coppery-red individuals assigned to the nominotypical subspecies are found further west in the Great Plains.  There are, however, certain populations in Missouri that show more or less suffusion of coppery-red coloration.  This is typically explained as hybrid influence, as Missouri lies on the western edge of the distributional range of subspecies generosa.  However, we have only seen these coppery-red indications on the eastern side of Missouri, while populations on the western side of the state along the Missouri River exhibit typical dark brown coloration.  The population here in St. Louis Co. is the third population we have found to show this coppery-red influence, and in fact most of the individuals I saw exhibited greater or lesser amounts of this coloration.  My personal belief is that there is no genetic basis for this subspecific distinction, but that the differences in color are instead related to conditions of the soil in which they live—possibly pH.  Sand habitats in the eastern United States are typically acidic, while alkaline soils abound in the Great Plains (formerly a vast sea bottom).  Hey, it’s a thought!

Big sand tiger beetles remain one of my favorite beetle species in Missouri.

The combination of striking coloration and bold white markings exhibited by big sand tiger beetles might seem to make them quite conspicuous and vulnerable to predation—especially in the open, sparsely vegetated areas that they inhabit; however, against the textured sandy substrates on which they are found they are almost impossible to detect until they move.  I’ve learned not to try to see them first and sneak up on them, as this is a lesson in futility.  Rather, I simply walk through an area and fix my sights on individuals as they take flight, watching them as they fly and eventually land and then sneaking up to the spot where I saw them land.  I generally need to stop about 8-12 feet out and study the spot carefully to pick them out, and then I can continue sneaking up on them.

Photo Details: Canon 50D w/ 100mm macro lens (ISO 160, 1/200 sec, f/16), Canon MT-24EX flash w/ DIY oversized concave diffuser. Typical post-processing (levels, minor cropping, unsharp mask).


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

Friday Flower – “Palo Borracho”

Ceibo may be Argentina’s national flower, but Ceiba is its most iconic flower.  That’s right—Ceibo and Ceiba are two, completely unrelated species!  Ceibo is the common name in Argentina for Erythrina crista-galli, a tree in the family Fabaceae, while Ceiba is a genus of flowering trees in the family Bombacaceae that includes the species pictured above—Ceiba speciosa (syn. Chorisia speciosa), known in Argentina as “Palo Borracho.”  This translates literally to “drunken stick”—a reference to the pot-bellied trunk with narrowed base that gives the tree the appearance of a wine bottle (Haene and Aparicio 2007).  Native to the dry forests of northeastern Argentina, C. speciosa has become an enormously popular street tree in the country due to their dazzling displays of hot pink blossoms, especially in Buenos Aires whose green spaces and wide boulevards are lined with grand old specimens.

Interspersed amongst the pink flowering trees are occasional specimens with the flowers mostly white but otherwise looking much the same as C. speciosa.  These are the closely related species C. chodattii (syn. Chorisia insignis), or Yuchán.  This species is native to more western, even drier areas of northern Argentina than C. speciosa and has also become popular as an ornamental tree in urban areas, though it has been planted with less frequency than its hot pink-flowered congener.

Bombacaceae also contains the famously odd baobab and kapok trees—also distingished by bulging trunks that serve as an adaptation for water storage in seasonally dry environments.  The trunks of Ceiba trees exhibit an additional water conservation adaptation with thick, conical-shaped thorns that are also capable of water storage.  The young tree picture here was photographed in Campinas, Brazil and exhibits the green coloration typical of younger trees that functions to augment their photosynthetic capabilities. In fact, the dry forests in which Ceiba spp. evolved often contain a number of unrelated plants that also are thorny and have green bark.


Haene, E. and G. Aparicio.  2007.  100 Trees of Argentina. Editorial Albatros, Buenos Aires, República Argentina, 128 pp.

Copyright © Ted C. MacRae 2011

Feasting on the bounty

Brood XIX periodical cicadas were not the only insects appearing en masse last week at Sam A. Baker State Park in Missouri’s southeastern Ozark Highlands.  As I walked the upland trail, I thought I felt ‘raindrops’ for awhile before realizing that it was frass.  Little pieces of fresh young leaves littered the trail around me, and I realized that an outbreak of caterpillars was hammering the oak trees in this forest.  Unlike the cicadas, which were encountered primarily in the bottomland forest along Big Creek, the rain of poop was restricted to the uplands.  Not surprisingly, I saw caterpillar hunters, Calosoma spp. (family Carabidae—the real Carabidae, not the tiger beetle Carabidae that I’ve begrudgingly had to accept) about as abundantly as I’ve ever seen them.  At first I didn’t notice them until I would scare one up, then spend several frustrating minutes trying to photograph a beetle that just would not stop running.  I tried a few and gave up—after all, they’re just ground beetles (i.e., real ground beetles).  Eventually, I realized that if I noticed them before they noticed me, I could sneak up on them and have my way with them (photographically speaking, that is).  I even found that I could preen nearby leaves and sticks for composition if I did it carefully enough.  Here are a couple of my favorite shots on the day.

I would presume these to represent the fiery searcher, Calosoma scrutator, but apparently C. wilcoxi is similar in appearance.  According to comments by several BugGuide users, C. scrutator is larger (25mm or more in length), has more elongated mandibles and head, and the color of the central purple area of the pronotum is more intense.  Based on those comments, I would say the two individuals in these photographs are C. scrutator.  However, they also note some differences in temporal occurrence that don’t seem to support that.  Moreover, the many individuals I saw that day ranged in size from these larger individuals to some notably smaller ones.

Copyright © Ted C. MacRae 2011

Love is in the air!

My first tiger beetle photograph of the season. There’s nothing more adorable than Spring love!

Cicindela tranquebarica (oblique-lined tiger beetle) | St. Joe State Park, Missouri

Photo details: Canon 50D w/ 100mm f2.4 macro lens (ISO 160, 1/200 sec, f/16), Canon MT-24EX twin flash w/ DIY oversized concave diffuser.

Copyright © Ted C. MacRae 2011