Two new species of Agrilus from Mexico

ResearchBlogging.orgThe enormous, cosmopolitan genus Agrilus (family Buprestidae – commonly called jewel beetles or metallic woodboring beetles) contains nearly 4,000 described species (Bellamy 2008). With many more still awaiting description, it is perhaps the largest genus in the entire animal kingdom (Bellamy 2003). Agrilus species are primarily twig and branch borers, utilizing recently dead wood for larval development – although there are notable exceptions, e.g. Agrilus anxius (bronze birch borer), A. bilineatus (twolined chestnut borer), and A. planipennis (emerald ash borer), which attack the trunks of living trees and, thus, are of significant economic importance in forest and ornamental landscapes. Host specificity among Agrilus species ranges from highly monophagous – associated exclusively with a single plant species – to rather oliphagous – utilizing several, usually related, plant genera. Adults of Agrilus species are most often found on the foliage of their larval hosts and do not generally visit flowers, as is common in some other genera (e.g., Acmaeodera and Anthaxia). Interestingly, despite the diversity and worldwide distribution of the genus, no species of Agrilus are known to be associated with coniferous plants – a fact that has limited their expansion into the vast northern boreal forests.

Texas, Bexar Co., San Antonio, nr. Fort Sam Houston, em. 25.iv-14.v.1997 ex Phoradendron tomentosum coll. ii.1997, D. Heffern & D. W. SundbergAs can be imagined by its enormity, a comprehensive understanding of the genus will remain a distant goal for many years. Progress will come incrementally, as formal descriptions of new species gradually improve our knowledge of the fauna that exists in each of the world’s main biogeographic provinces. In a recent issue of the online journal Zootaxa, Dr. Henry Hespenheide (UCLA) describes two new species of Agrilus from Mexico. These two species are interesting because of their association with ‘mistletoe’ plants in the genus Phoradendron (family Viscaceae1), obligate hemiparasites that attach to branches and stems of various woody trees and shrubs in tropical and warm temperate regions of the New World. Plants in this genus are known to support a variety of host-restricted insect herbivores, principally in the orders Hemiptera, Coleoptera and Lepidoptera. A single buprestid species has been associated with Phoradendron to this point – Agrilus turnbowi, recently described from specimens reared from dead stems of Phoradendron tomentosum attached to mesquite (Prosopis glandulosa) in southern Texas (Nelson 1990) and pictured here from a specimen in my collection that was reared from dead mistletoe collected at the type locality. At the time of its description, this species was not relatable to any of the other known species in the genus.

1 The Angiosperm Phylogeny Group (2003) includes the Viscaceae in a broader circumscription of the family Santalaceae. However, recent molecular studies suggest the Santalaceae are polyphyletic, with strong support for Viscaceae as a distinct, monophyletic clade (Der & Nickrent 2008).

The two new Mexican species – A. andersoni from Guerrero and Puebla (Figs. 1-3), and A. howdenorum from Oaxaca (Figs. 4-6) – are apparently related to A. turnbowi, which they resemble by their purplish-red coloration and complex pattern of golden setae on the elytra. They are also superficially very similar to each other but differ most notably in size and the overall color and pattern of setae on the elytra.

Figures 1–3. Agrilus andersoni Hespenheide: 1. dorsal habitus; 2. lateral habitus (scale bar indicates 2.0 mm); 3. genitalia of male (scale bar indicates 0.5 mm) (from Hespenheide 2008).

Figures 4–6. Agrilus howdenorum Hespenheide: 4. dorsal habitus; 5. lateral habitus (scale bar indicates 2.0 mm); 6. genitalia of male (scale bar indicates 0.5 mm) (from Hespenheide 2008).

Hespenheide speculates that the color and pattern of the golden setae on the elytra may serve to make the beetles less conspicuous by disruptive coloration, noting the similar coloration of the setae to the leaves of Phoradendron as seen in the photograph of Agrilus howdenorum on its host plant (Fig. 7). This form of crypsis may also be enhanced by the purplish-red ground coloration of the adult, which resembles that of the small, darkened blemishes often observed on the foliage of these plants.

Figure 7. Agrilus howdenorum adult on mistletoe host plant near Diaz Ordaz, Oaxaca, México. The golden setae on the elytra are similar in color to the leaves of the mistletoe and may function as a disruptive color pattern. Photograph by C.L. Bellamy (from Hespenheide 2008).


Angiosperm Phylogeny Group. 2003. An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II. Botanical Journal of the Linnean Society, 141: 399-436.

Bellamy, C. L. 2003. The stunning world of jewel beetles. Wings, Essays on Invertebrate Conservation, 26(2): 13-17.

Bellamy, C. L. 2008. A World Catalogue and Bibliography of the Jewel Beetles (Coleoptera: Buprestoidea), Volume 4: Agrilinae: Agrilina through Trachyini. Pensoft Series Faunistica No. 79, 722 pp.

Der, J. P. & D. L. Nickrent. 2008. A Molecular Phylogeny of Santalaceae (Santalales). Systematic Botany, 33(1):107-116.

Hespenheide, H. A. (2008). New Agrilus Curtis species from mistletoe in México (Coleoptera: Buprestidae) Zootaxa, 1879, 52-56

Nelson, G. H. 1990. A new species of Agrilus reared from mistletoe in Texas (Coleoptera: Buprestidae). The Coleopterists Bulletin, 44(3):374-376.

The Five Things Meme

Adrian Thysse has tagged me with The Five Things Meme:

5 things I was doing 10 years ago:

  • Enjoying my second year of fatherhood
  • Revising the North American species of the cerambycid beetle genus Purpuricenus
  • Collecting beetles in Arizona with Chuck Bellamy and Art Evans
  • Learning to speak Spanish
  • Worrying a lot more about career advancement than I do now

5 things on my to do-list today:

  • Take kids to the dentist – check
  • Put up kids tether ball pole – abort (pole sections don’t fit, need to exchange)
  • Vacuum carpets throughout the house – check
  • Hang pictures I took of wildflowers this spring (chosen, nicely framed, and given to me by my wife for my birthday) – check
  • Short 20-mile bike ride – CHECK!

5 snacks I love:

  • Spudmaster CollosalChips, handmade in the heart of Missouri
  • GK Select Gourmet Blend nuts (collosal cashews, almonds, macadamias & pecans)
  • Raspberry or blueberry scone and coffee
  • Pemmican Premium beef jerky, peppered
  • Chocolate covered almonds/raisins/strawberries/etc.

5 things I would do if I was a millionaire:

  • Help my dad retire
  • Enroll kids in private school
  • Substantial contributions to The Nature Conservancy
  • Buy a few acres on the west shore of Lake Tahoe

5 places I’ve lived:

  • Kansas City, Missouri (childhood)
  • Columbia, Missouri (university)
  • St. Louis, Missouri (1st job)
  • Sacramento, California (2nd job)
  • St. Louis, Missouri (3rd job)

5 jobs I’ve had:

  • Injection Mold Operator (3 mos)
  • Pizza Cook (9 mos)
  • Research Assistant (2 yrs)
  • Agricultural Inspector (8 yrs)
  • Research Entomologist (18 yrs)

And I tag Allison Vaughn, Doug Taron, Hugh, cedrorum and Huckleberry.

Pardon my introspection

In addition to this blog, I maintain a second, older blog called Bikes, Bugs, and Bones. That snarkier, decidedly less erudite site was my first venture into the world of blogging, initiated some two and a half years ago not due to any particular vision on my part, but more as a reaction to other blogs that were popping up by people I knew in the St. Louis cycling scene. At that time, I was deeply immersed in the world of amateur bike racing, and a blog seemed to be a natural outlet for reporting my take on the races in which I participated. The title – Bikes, Bugs, and Bones – was a reflection of my propensity to be interested in too many things (with not enough time). In reality, however, my surging interest in cycling had by then pushed my longer held entomological and natural history interests to the back burner, and my posts on that blog – then and now – dealt almost exclusively with bicycles and racing. For several reasons racing was something I needed to do, and I had a good run – winning 14 races in seven years (including three state championships) and crowing it all with a highly respectable finish in the 2007 Etape du Tour (an amateur race held on the “Queen stage” route of the Tour de France). My interest in entomology and natural history never waivered during this time, but the demands of training relegated any meaningful field work to short windows before the racing season began and after it ended each year. Eventually, the entomologist in me could be suppressed no longer, and at the end of last year I decided that I needed to get back to doing what I loved – bug collecting! I made a commitment to return entomology field work to its rightful place as my first priority (after family and work, of course) and race bicycles as time permitted. (I have since completely retired from racing, although I still ride and maintain Bikes, Bugs, and Bones as an outlet for discussing all things cycling.) As an expression of that renewed commitment, I started a new blog – this blog – and after much frustration finding that every blog name I thought of had already been thought of by someone else (and generally abandoned after only a few posts) settled on the name Beetles In The Bush. One year ago today – November 24, 2007 – I posted my first entry to this new blog (a subsequent entry, a list of my publications, was backdated to November 23).

Beetles In The Bush started with a simple mission – to document my entomological and other natural history experiences and provide an outlet for the photographs that I was beginning to take. Late fall is not the best time to begin an insect blog, especially with no insect photos on hand to serve as starter material. As a result, my initial posts appeared rather infrequently – primarily whenever I had the opportunity to do a winter hike. It was those first few hikes, however, and my efforts to write something interesting about the natural history represented in the photographs that I took, that called attention to what I realized was a glaring gap in my overall knowledge of natural history. I was a competent entomologist, to be sure, but that competency did not extend to general botany (other than the mostly woody plants with which the insects I studied were associated), or to the natural communities in which those plants and insects occurred, or to the geology of the landforms that contained those natural communities, or to the manner in which these fields intersect, an understanding of which I would have to have before I could consider myself a competent natural historian. More than just an outlet for posting pictures and stories about my adventures, Beetles In The Bush also quickly became a tool to help me learn more about botany, ecology, geology, and related fields. I have read more non-entomology literature in the past year than I have since earning my degrees, and since knowledge and passion are intimately linked in a positive feedback loop, I’ve found myself becoming even more passionate about entomology, too. I still have much to learn – I am a work in progress, far from complete. But in this case, it is the journey that is also the reward.

Like all bloggers, I’d like to think that I have a large, regular following, and that over time more and more people will find my writings interesting and worthy of their time. The numbers don’t support this – as of this one-year anniversary, Beetles In The Bush has received 6,987 hits – not triffling but by no means extraordinary. While the graph below shows steady growth during the first year of existence, the numbers don’t come within a rifle’s shot of some of the really popular natural history and science blogs. I surmise the main reason for this involves a relatively lower posting frequency – a little more than once per week on average instead of the daily or near daily frequency seen with many blogs. I suppose also my relatively specialized subject matter and tendency to ramble on are contributing factors. I have thought about writing smaller, more frequent posts and expanding my subject matter to create greater interest; however, in doing this I realized that what I enjoy most is writing stories about the things that interest me – stories that teach, stories that impart a sense of the passion that I feel, stories that allow me to reflect on what I’ve learned and what I still don’t know. If that makes a broad, daily readership less likely, so be it – I understand now that I’m doing this as much for me as anyone else. So, I mark this first anniversary with a resolution to wean myself from the lure of trying to increase traffic and refocusing my efforts on doing what I enjoy most – writing silly little stories about the things I stumble upon on my journey to become a better natural historian. For the readership that I do have, I am grateful. More importantly, I am thankful for the goodly number of “friendships” that have resulted from these writings. Thank you for your interest, and I sincerely hope that some day I have the chance to meet many of you in person.

Beetles in the Bush - first year summary

A new species of Xenorhipus from Baja California

ResearchBlogging.orgA few months ago I discussed Trichinorhipis knulli of the tribe Xenorhipidini (family Buprestidae). Members of this tribe exhibit highly sexually dimorphic antennae, with the distal segments of the male antennae highly modified into a very extended flabellate or lamellate condition. The surfaces of the flabellae/lamellae are covered with numerous, presumably olfactory sensillae that are lacking on female antennae (which retain the unmodified serrate condition), strongly suggesting a function involving detection of female sex pheromones. Although chemosensory structures are present on the antennae of nearly all buprestids, the extreme modification exhibited by the males of species in this tribe is not a common occurrence. Nevertheless, similar modifications have evolved independently in a few other genera within the family, including Knowltonia (four species in western North America), Mendizabalia and Australorhipis (monotypic genera in South America and Australia, respectively), and two species of the enormous Australian genus Castiarina. Indeed, males of Knowltonia and the two Castiarina species possess what might be termed ‘bipectinate’ or ‘biflabellate’ antennae due to dual projections from the terminal antennomeres (see Bellamy & Nylander 2007 for a more complete discussion of male antennal modifications in Buprestidae). The tribe Xenorhipidini is the most diverse group in which these modifications have arisen, comprised of the monotypic Trichinorhipis from California and the closely related Hesperorhipis (four species in Arizona and California) and Xenorhipis (until now, 14 species from North and South America and the West Indies).

Xenorhipis bajacalifornica Westcott, 2008 – holotype ♂ (1) & allotype ♀ (2).
Photos by Steve Valley (Oregon Department of Agriculture).

In a recent issue of the online journal Zootaxa, Rick Westcott (Oregon Department of Agriculture) describes a new species of Xenorhipis from the Cape Region of Baja California Sur, Mexico. Although assigned to the genus Xenorhipis, the new species – X. bajacalifornica – seems to bridge the gap between the genera Xenorhipis and Hesperorhipis. As currently recognized, Xenorhipis is distinguished from Hesperorhipis by the shape of the posterior coxal plates, which are scarcely narrowed laterally in the former genus, while in the latter genus they are triangular and with the hind margin strongly oblique. In X. bajacalifornica the posterior coxal plates are somewhat triangular but not as acute laterally as in some species of Hesperorhipis. Xenorhipis bajacalifornica also differs from other described Xenorhipis in its strongly abbreviated elytra, which in males barely reach the second ventrite – similar to species of Hesperorhipis. Other described Xenorhipis exhibit less abbreviated elytra, which cover at least the first three ventrites and in some species almost the entire abdomen. Despite these similarities to Hesperorhipis, a consistent distinguishing character between the two genera was found in the male antenna – in Xenorhipis the flabellar processes begin with the second antennomere, while in Hesperorhipis they begin with the third. It was on this basis that the new species was assigned to the genus Xenorhipis. (The genus Trichinorhipis differs from both Xenorhipis and Hesperorhipis by its rounded rather than quadrate pronotum and its unabbreviated elytra that cover the entire abdomen and has, as a result, been placed in its own subtribe.)

Xenorhipis brendeli ♂Xenorhipis brendeli ♀The photos left show the male (L) and female (R) of Xenorhipis brendeli, the only species in the tribe occurring in eastern North America (west to Minnesota and eastern Texas). Adults of this species are not commonly encountered and have been collected on a variety of deciduous hardwoods but reared almost exclusively from species of hickory (genus Carya). These individuals were reared from dead branches collected in southeastern Missouri – the male from pecan (Carya illinoensis) and the female from shellbark hickory (Carya laciniosa). The male exhibits the scarcely abbreviated elytra that cover almost the entire abdomen (as discussed above). Stan Wellso reported large numbers of males attracted to caged live females in Texas, apparently responding to sex pheromones released by the females.

Xenorhipis osborni ♀Xenorhipis osborni ♂This is another species in the genus – Xenorhipis osborni – known from west Texas. Joseph Knull described the species in 1936 from specimens collected in the Davis Mountains on whitethorn acacia (Acacia constricta), but larval hosts remained unknown until I reared a series of these specimens from dead branches of black acacia (Acacia rigidula) collected above the Pecos River in Val Verde County. I’ve also reared a few specimens from dead branches of catclaw acacia (Acacia greggii) collected in Big Bend National Park, and I wouldn’t be surprised if it breeds in other species of acacia. Again, in this speices the elytra are only slightly abbreviated, though more so than in Xenorhipis brendeli above and also more so in the male (L) than in the female (R). The male of this species is one of the prettiest I’ve encountered in the tribe.

Hesperorhipis albofasciatus ♂Hesperorhipis albofasciatus ♀The genus Hesperorhipis is illustrated here by these photos of H. albofasciatus. These specimens were reared by Rick Westcott from dead branches of walnut (Juglans sp.) – its only known host – collected in Tulare County, California. The elytra in this species are much more abbreviated than in Xenorhipis brendeli and X. osborni but similar to those of X. bajacalifornica – again with the male (L) exhiting greater abbreviation than the female (R). The three remaining species of Hesperorhipis exhibit even more highly abbreviated elytra than H. albofasciatus.

Dr. Charles Bellamy (California Department of Food and Agriculture) is currently revising the tribe. It will be interesting to see how, ulimately, he treats Xenorhipis and Hesperorhipis, given the blended characters exhibited by some species.


Westcott, R. L. (2008). A new species of Xenorhipis LeConte and of Mastogenius Solier from Mexico, with a discussion of Chrysobothris ichthyomorpha Thomson and its allies and notes on other Mexican and Central American Buprestidae (Coleoptera) Zootaxa, 1929, 47-68

Magnificently Monstrous Muscomorphs

I suppose tiger beetles have gotten more than their fair share of attention here lately, so for this post I thought I’d highlight insects of a completely different group – flies! Admittedly, as a coleopterist, I tend to view flies with much the same disdain as your average insect non-enthusiast – as pesky, pestiferous vermin worthy of little more attention than a decisive swat. I don’t begrudge them their amazing diversity – at ~100,000 described species worldwide, they are strong contenders with the Lepidoptera and Hymenoptera as the second largest order of insects (of course, you need all three of these orders combined to match the diversity of the Coleoptera). I am also prepared to accept that they may well represent, at least morphologically, the pinnacle of insect evolution (a position that a few hymenopterists I know might argue with) due to their amazing flight capabilities and the morphological adaptations they have developed for such. These include the development of aristate antennae for detecting wind speed, the conversion of the second pair of wings into stabilizing organs (halteres), and the ability to beat the remaining pair of wings at incomprehensible rates – up to 1,000 times per second in some very small midges (even more baffling when one considers that the wing “beat” is actually just a passive result of rhythmic distortions of the thoracic box). I even acknowledge that the vast majority of fly species are not even pests, living their lives innocuously as herbivores, scavenging organic matter that nothing else wants, and preying upon or parasitizing other insects, including important agricultural pests. Still, flies bug me – mosquitoes prevent me from sleeping under the stars without a tent, deer flies drone around my head incessantly while I’m trying to stalk an elusive tiger beetle, stable flies trick me into assuming they are just another house fly (until they bite me!), house flies (the real ones) rudely land on my sandwich with their filthy feet, and eye gnats insist on committing hary kary in my eyes as I walk the trails (I won’t mention their other common name, derived from their habit of clustering around exposed canid genitalia).

There is, however, one group of flies that possess “cool factor” rivaling that of even the most popular insect groups – robber flies and their kin. I’ve always picked them up as an aside, even sending them off for authoritative ID and constructing an inventory of the species in my collection. The brute of a fly pictured here is not a true robber fly, but in the related family Mydidae. Mydus clavatus can be recognized easily in the field by its large size and distinctive black coloration with red/orange on top of the 2nd abdominal segment. Presumably this is an example of Batesian mimicry modeled upon spider wasps (family Pompilidae) in the genus Anoplius. This mimicry allows them to fly rather boldly in the open and is so persuasive that it can not only fool the casual observer, but even the most knowledgable of entomologists might be loathe to handle it despite knowing better. Although common across the eastern U.S., aspects of its life history are poorly understood. Adults have been reported to be predators of other insects, but apparently there are some doubts about the veracity of such reports. Patrick Coin of BugGuide has observed adults (males?) taking nectar from flowers and has suggested that reports of predation by adults might have been an erroneous assumption due to their relation and resemblance to robber flies. Larvae are reported to be predaceous on woodboring beetle larvae, and I have reared adults of this species from a dead sycamore (Platanus occidentalis) stump in southern Missouri that was infested with mature larvae of the large buprestid species, Texania campestris. This habit is similar to robber flies of the genus Laphria, which mimic bumble bees and carpenter bees.

In Greek mythology, Promachos (Προμαχοε) was “the champion” or one “who leads in battle” – an appropriate generic name for the so-called “giant robber flies” of the genus Promachus. These large flies are dominant and fearless predators that will capture just about any flying insect – even adult dragonflies. There are three species of Promachus in the eastern U.S. that exhibit the yellow and black tiger striping of the abdomen seen in this individual, identified as a female Promachus hinei by Herschel Raney at BugGuide due to its reddish femora and occurrence in the central U.S. Promachus rufipes is similar but has black femora with distinctly orangish tibiae and is more common in the southeastern U.S., whereas P. vertebratus has more muted two-toned legs with smaller dark areas dorsally on the abdominal segments and is more common in the northern states. Additional species occur in the region but lack the tiger striping of the abdomen, and even more species occur in the western U.S. Members of this genus generally lay their eggs on the ground near grass roots, and the larvae burrow into soil after hatching and feed on soil insects, roots, and decaying matter before pupating within the soil in an unlined cell.

During my recent trip to Nebraska I encountered this related robber fly genus Proctacanthus, also determined by Herschel provisionally as P. milbertii. These large robber flies with a prominent beard are similar in habit to Promachus species, laying their eggs in crevices in soil and the larvae feeding on soil insects, roots, and decaying plant matter. Proctacanthus milbertii is a late season species that occurs across much of the U.S. and reportedly loves butterflies. However, Joern & Rudd (1982), in studying predation by this species in western Nebraska (where the individual pictured here was photographed) found that grasshoppers made up 94% of the prey captured by this species. Interestingly, nearly all of the remaining prey captures were other P. milbertii, which was carefully verified as such since mating postures can be easily mistaken for prey handling positions. Grasshopper prey species taken by this species were most strongly influenced by availability rather than size, suggesting that even the largest grasshopper species could be captured as easily as smaller species – a testament to the ferocity of this robber fly.

Another family of flies modestly related to robber flies and also ranking high in “cool factor” are the bee flies (family Bombyliidae). The scaly bee fly, Lepidophora lepidocera (ID confirmed by Joel Kits at BugGuide), is a particularly attractive member of the family. The distinctive, hunch-backed shape of this southern U.S. species is shared with the more northern L. lutea, from which it is distinguished by having pale scales only on the 5th abdominal segment and not on the 4th also. Most bee flies are presumbably mimics of – yes – bees; however, the species in this genus might actually be mimics of robber flies instead. Adults are most often seen taking nectar from flowers – this individual was taken on flowers of tall boneset (Eupatorium altissimum). Larvae are characterized by Sivinski et al. (1999) as kleptoparasites on the provisions of solitary wasps in the families Vespidae and Sphecidae – meaning that the larva does not parasitize wasp larvae directly, but instead usurpes the nest provisions on which the wasp larvae were supposed to feed. The little thieves!

Cicindela scutellaris lecontei x scutellaris unicolor intergrades in southeast Missouri

An individual from Sand Prairie Conservation Area.  Note the uniform blue-gray coloration and complete lack of maculations, making this individual indistinguishable from true unicolor.Cicindela scutellaris (festive tiger beetle) is widely distributed in the U.S., having been recorded from most areas east of the Rocky Mountains except Appalachia, the lower Mississippi River delta, and south Florida. Within this range, the species occupies deep, dry sand habitats without standing water. It is often found in the company of Cicindela formosa (big sand tiger beetle), whose range largely coincides with that of C. scutellaris (except the southeastern Coastal Plain). More than any other North American Cicindela, populations of this species show extraordinary variability in color across its range of distribution. Seven geographically recognizable subspecies are generally accepted, with considerable variation evident within some of these and along zones of contact between them.

An individual from further south on the Sikeston Ridge (~20 mi S of Sand Prairie Conservation Area).  Note the generally blue-green coloration as in unicolor, but it also exhibits fairly well developed maculations and a suffusion of maroon color on the elytra - distinct influences from subspecies lecontei.The greatest portion of the species’ range is occupied by nominotypical populations in the Great Plains and subspecies lecontei in the Midwest and northeast. Similar to what I’ve noted in previous posts for other species, a broad zone of intergradation between these two subspecies occurs along the upper Missouri River. Other subspecies occupy more limited ranges along the upper Atlantic Coast (rugifrons), southeastern Coastal Plain (unicolor), eastern Texas and adjacent areas of northwestern Louisiana and southwestern Arkansas (rugata), and north-central Texas (flavoviridis), and the highly restricted and disjunct yampae is found only in a small area of northwestern Colorado. Populations in the upper Midwest and Canadian prairie are sometimes regarded as distinct from lecontei (designated as subspecies criddlei) due to their broadly coalesced marginal elyral maculations, and an apparently disjunct population of small, blue individuals in south Texas may also be regarded as subspecifically distinct.

Another individual from Sand Prairie Conservation Area.  It is similar to the unicolor-type individual in Photo 1 but also exhibits small maculations derived from its lecontei influence.Although Missouri lies well within the boundaries of its range, this species has been found in only three widely-separated parts of the state – near the Missouri River in the northwest part of the state, near the Mississippi River in the extreme northeast corner, and in the southeastern lowlands (formally known as the Mississippi River Alluvial Basin). The two northern Missouri populations are assignable to and typical of lecontei, with their uniform dull maroon to olive green coloration and continuous to near-continuous ivory-colored border around the outer edge of the elytra. Additional dry sand habitats occur along the lower Missouri River in central and east-central Missouri and along some of the larger rivers that drain the Ozark Highlands; however, this species has not been located in these habitats despite their apparent suitability and occurrence of C. formosa with which it frequently co-occurs. The reasons for this distributional gap between the northern and southern populations – some 400 miles in width – remain a mystery. The southeastern Missouri population is not clearly assignable to any subspecies, apparently representing an intergrade between lecontei to the north and unicolor to the south. Accordingly, individuals from this area are known by the unwieldy appellative “Cicindela scutellaris lecontei x scutellaris unicolor intergrade.” Pearson et al. (2005) states that intergrades between lecontei and unicolor are evident only in northern “Missouri” (an obvious error for Mississippi) and Tennessee. Thus, the existence of intergrades in southeastern Missouri suggests that the zone of intergradation extends further north than previously realized.

A second individual from ~20 mi S of Sand Prairie Conservation Area.  Similar to the individual in Photo 2 except with smaller maculations.  Note the gorgeous suffusion of maroon, especially on head and pronotum - a spectacular individual.Prior to this season, I had located two main population centers in the southeastern lowlands – one at Holly Ridge Conservation Area in Stoddard County, and another at Sand Pond Conservation Area in Ripley County. Holly Ridge is located on Crowley’s Ridge – an erosional remnant of Tertiary sand and aggregate sediments left behind by the late Pleistocene glacial meltwaters whose scouring action formed the surrounding lowlands, while the sandy sediments at Sand Pond were deposited west of Crowley’s Ridge along the southeastern escarpment of the Ozark Highlands during that same period. These erosional and depositional events created the deep, dry sand habitats that Cicindela scutellaris requires. I had known also about the Sikeston Sand Ridge further to the east – another erosional remnant of Tertiary sands deposited by the ancient Ohio River – but had not explored it closely until this season when I initiated my surveys at Sand Prairie Conservation Area. I expected Cicindela scutellaris might occur here, and in my first fall visit in early September I found two individuals in the sand barrens (alongside Cicindela formosa). Another individual was seen here in early October, but more robust populations were observed at a small, high-quality sand prairie remnant (last photo) further to the south along the Sikeston Ridge, and around eroded sand barrens behind private residences still further to the south. Clearly, the species is well-established in the southeastern lowlands wherever open dry sand habitats can be found.

Sand prairie habitat for Cicindela scutellaris in southeast Missouri.  Note the well-spaced clumps of grass, in this case splitbeard bluestem.The individuals shown here exemplify the range of variation exhibited by Cicindela scutellaris populations in southeast Missouri. They greatly resemble subspecies unicolor by their uniform shiny blue-green coloration. Indeed, the individual in the first photo might well be classified as such due to the complete absence of white maculations along the elytral border. Most individuals, however, show varying development of such maculations, ranging from small disconneted spots to the more developed apical “C”-shaped mark – clearly an influence from subspecies lecontei. Another apparent lecontei influence is the suffusion of wine-red or maroon coloration that can be seen on the head, pronotum, and elytra of the individuals in photos 2 and 4. These characters make this population divergent from the typically monochromic unicolor (as its name suggests). Because of their bright green coloration and white maculations, individuals in this population greatly resemble subspecies rugifrons, but that subspecies is limited to the northern Atlantic seaboard. They also resemble the common and widespread Cicindela sexguttata (six-spotted tiger beetle) but can be distinguished from that species by the more noticeably domed profile of the elytra, rounded rather than tapered elytral apex, and dark labrum of the female (both sexes of C. sexguttata have a white labrum).

There is one additional sand ridge in Missouri’s southeastern lowlands – the Malden Ridge. This sand ridge occurs south of Crowley’s Ridge and is much smaller than the Sikeston Ridge. No significant remnant habitats remain on the Malden Ridge, but it is possible that sufficient areas of open sand remain that might support populations of C. scutellaris. Determining whether this is true will require some time studying Google Earth and even more time on the ground to search them out. If they do exist, however, it will be interesting to see what level of influence by lecontei is exhibited in this most southerly of Missouri populations. Only spring will tell!