Missouri

Prey bee mine

/ Ted C. MacRae / 12 Comments
Promachus hinei preying upon a small carpenter bee

Promachus hinei preying upon a small carpenter bee

Robber flies of the genus Promachus – the so-called “giant robber flies” – are among the more conspicuous and fearless predators seen in Missouri’s glades. Able to capture almost any flying insect regardless of size, this individual – seen at Long Bald Glade Natural Area in Caney Mountain Conservation Area – was found snacking on what, according to my hymenopterist friend Mike Arduser, appears to be a female individual of the genus Ceratina (the so-called small carpenter bees in the family Apidae). Of the three “tiger-striped” (referring to the yellow and black striping of the abdomen) species of Promachus in the eastern U.S. species, P. hinei is the most common in Missouri. It is distinguished from the more southeastern P. rufipes by its reddish versus black femora and from the more northern P. vertebratus by the larger dark areas dorsally on the abdominal segments and distinctly contrasting two-toned legs. Despite their common name and impressive size, however, they are not the largest robber flies that can be seen in these glades…

Photo details: Canon 100mm macro lens on Canon EOS 50D (manual mode), ISO-100, 1/250 sec, f/13, MT-24EX flash 1/4 power through diffuser caps.

Copyright © Ted C. MacRae 2009

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Ant-like Tiger Beetle

/ Ted C. MacRae / 23 Comments
Fig. 1. Adult female Cylindera cursitans

Fig. 1. Adult female Cylindera cursitans

One of the more recent of the 24 species of tiger beetles that we’ve collected in Missouri is Cylindera cursitans (Ant-like Tiger Beetle).  Although not yet formally recorded from the state, we’ve known about its occurrence here for some time now based on a single specimen deposited in the Enns Entomology Museum (University of Missouri).  With no more locality information to go on than the frustratingly vague “nr. Portageville,” my colleague Chris Brown and I made several attempts over the years to look for this species – eventually deciding that one particular spot where the highway stretched east of Portageville and dead-ended at the Mississippi River was the most likely collection site.  This locality, which we would come to call the “end of the hiway” spot (I suspect that every state with at least one tiger beetle aficionado has one or more so-named spots), proved to be a true tiger beetle “hot-spot,” with no less than 8 species of tiger beetles found along its sandy banks in our first few surveys.  However, C. cursitans was not among them, and success would only come with a little bit of serendipity when I received an email in 2007 from Kent Fothergill.  Kent explained that he had learned of me from my Missouri Tigers article (MacRae and Brown 2001), offered some comments about the tiger beetles that he had been finding since his recent move to southeast Missouri, and included full label data from the tiger beetles in the small collection of the Delta Research Center where his then-fianceé had secured a position as a research entomologist.  I wrote Kent back, thanked him for the data, and added this plea for assistance:

There is a single specimen of Cicindela cursitans in the UMC collection, it was collected in “nr. Portageville” on July 7, 1991.  We have tried several times without success to locate this species in Missouri – it’s the only species that we have not relocated.  If you have any interest in looking for it that would be great.  Attached is a pdf of recent paper describing its habits and biology in Nebraska.

Fig. 2. Adult female Cylindera cursitans ovipositing into substrate.

Fig. 2. Adult female Cylindera cursitans ovipositing in moist sand/loam substrate.

Little did I know how catalytic that comment would be – the very next day I received an email from Kent not only stating that he found it, but that he found it at the “end of the hiway” spot where we thought it might be.  A digital photo confirmed its identity, and the that weekend I blasted down to meet Kent and see the beetle for myself.  I would see just two beetles that day, but both were at a new locality about one mile south of where Kent had originally spotted them.  Kent would later find them at yet another locality further north along the Mississippi River, and in 2008 the three of us (Kent, Chris, and myself) conducted an intensive survey of potential habitats in southeastern Missouri that identified additional populations both north and south of the original localities.  We concluded that populations of C. cursitans, were restricted in southeast Missouri to the ribbons of wet bottomland forest that occupy the narrow corridor between the Mississippi River and the levees that confine it. However, the populations appeared secure and likely did not require any immediate conservation measures to ensure their long-term survival within the state. 

Fig. 3. Adult male Cylindera cursitans.

Fig. 3. Adult male Cylindera cursitans.

The bottomland forests that harbor C. cursitans in southeast Missouri (Fig. 3) contrast sharply with the wet meadow habitats reported for populations in Nebraska (Brust et al. 2005a). Within these habitats, the beetles themselves are very easily overlooked because of their small size and rapid running capabilities.  In addition, adult activity peaks in June and begin to wane in July.  The combination of these factors explains our initial difficulty in finding the beetle; however, with a proper search image and better understanding of its temporal occurrence and habitat preference, we have since found the beetles to be rather easily located.  A lingering question from last year’s survey is, how far north along the Mississippi River does C. cursitans occur? Furthermore, might the species also occur in northeast Missouri due to its proximity to the Nebraska populations?  Most of Missouri straddles a curious distributional gap that separates the bottomland forest dwelling populations in the southeast from the wet meadow dwelling populations in the upper Great Plains (Hoback and Riggins 2001). This has led some authors to suggest that the observed distribution represents two disjunct forms and potentially two species (Ron Huber, pers. comm.). Additional surveys of potential habitat further north along the Mississippi River and in northwest Missouri along the Missouri River could prove useful in confirming or refuting that suggestion. 

Fig. 3. Habitat for Cylindera cursitans, along Mississippi River, vic. Donaldson Point Conservation Area, New Madrid Co., Missouri.

Fig. 4. Habitat for Cylindera cursitans, along Mississippi River, vic. Donaldson Point Conservation Area, New Madrid Co., Missouri.

While such surveys were not possible this year, long-time fieldmate Rich Thoma and I were able to visit the Southeastern Lowlands in June to examine a few habitats along the Mississippi River found a little further north of the northernmost extent of our 2008 survey area. We succeeded in finding another population at one of these sites near the northern limit of the Southeastern Lowlands.  The individuals shown here (Figs. 1-3) were collected from that location (extreme northeastern Mississippi Co.), confined on local sand/loam substrate, and photographed a few days later.  In one of the photos (Fig. 2), a female can be seen in the act of ovipositing into a hole dug into the substrate with her ovipositor.  The more observant readers might notice a strong resemblance between this species and another species to which I have devoted several posts, Cylindera celeripes (Swift Tiger Beetle).  These two species are, in fact, quite closely related and can be distinguished by characters of the elytra (posterior portion not or only slightly expanded and lateral white maculations complete in cursitans, distinctly expanded and maculations reduced in celeripes) (Pearson et al. 2006), habitat (cursitans in moist lowland sites, celeripes in dry upland sites), and distribution (southeast Nebraska/southwest Iowa is the only area where the distributions of these two species overlap, although C. celeripes has not been seen in Nebraska for nearly 100 years! (Brust et al. 2005b)).

Photo details:
Figs. 1-3: Canon 100mm macro lens with Kenco extension tubes (68mm) on Canon EOS 50D (manual mode), ISO-100, 1/250 sec, f/18, MT-24EX flash 1/2 power through diffuser caps.
Fig. 4: Panasonic DMC-FX3 (landscape mode), ISO-100, 1/25 sec, f/2.8, natural light.

REFERENCES:

Brust, M., W. Hoback and C. B. Knisley.  2005a.  Biology, habitat preference, and larval description of Cicindela cursitans LeConte (Coleoptera: Carabidae: Cicindelinae).  The Coleopterists Bulletin 59(3):379-390.

Brust, M. L., S. M. Spomer and W. W. Hoback.  2005b.  Tiger Beetles of Nebraska.  University of Nebraska at Kearney.  http://www.unk.edu (Version 5APR2005).

 

Hoback, W. W. and J. L. Riggins.  2001.  Tiger beetles of the United States.  Jamestown, ND: Northern Prairie Wildlife Research Center Online.  http://www.npwrc.usgs.gov/resource/distr/insects/tigb/index.htm (Version 12DEC2003).

MacRae, T. C., and C. R. Brown. 2001. Missouri Tigers. Missouri Conservationist 62(6):14–19.

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 2009

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North America’s smallest rattlesnake

/ Ted C. MacRae / 24 Comments

Despite tramping through the brush with great frequency during most of my life, I haven’t really seen that many noteworthy reptiles.  I don’t know whether its because I’ve failed to actually encounter them or whether my singleminded obsession with insects above all other things natural has instead prevented me from seeing what was right in front of me.  Regardless of the reason, all that has seemed to change during the past two seasons (strangely coincident with my decision to start carrying a camera), and I now seem to be enjoying a bit of a reptile bonanza.  Last summer I featured a super-aggressive prairie rattlesnake from a trip to the Black Hills of South Dakota and an uncooperative dusty hognosed snake from Missouri’s critically imperiled sand prairies (both first-time sightings for me).  The reptilian treats continued this year – I saw my first juvenile Osage copperhead in May to go along with the several adults that I’ve encountered, and shortly afterwards during a June trip to northwestern Oklahoma I was treated to a gorgeous male eastern collard lizard, two Texas horned lizards, and a much more cooperative western hognosed snake (the last two being first-time sightings for me).  There was another herp that I saw during that Oklahoma trip, but I did not feature it here because I had stupidly declined to strap the camera bag to my back during a quick look at a roadside habitat.  That sighting was another first-timer for me – a western pygmy rattlesnake (Sistrurus miliaris streckeri).  I’m no herp expert, so wasn’t sure what it was at the time, but I later learned that its small size and distinctive markings were quite diagnostic.

IMG_1014_1200x800
Western pygmy rattlesnake – Sistrurus miliarius streckeri

Amazingly, I encountered this same species again just a few weeks later during a visit to the White River Hills of extreme southwestern Missouri.  It was during the second of two trips to the region to search for the stunningly beautiful bumelia longhorned beetle, Plinthocoelium suaveolens plicatum (family Cerambycidae), and the weather during that day – continuous drizzle and low, threatening clouds – had not been at all conducive for finding such a sun loving beetle.  After searching an area where I knew the beetles occurred, without success, daughter Madison and I resigned that the drizzle was here to stay and decided to pass the rest of the day with some hiking at one of Missouri’s most spectacularly wild and beautiful places, Hercules Glades Wilderness.  A splendid mix of post oak savannahs and limestone glades intersperses through the oak/hickory forests in these rugged hills, creating some of Missouri’s most scenic vistas.  Near the end of the hike at the edge of one of these glades on the high point of Coy Bald, I saw this little individual coiled up underneath an eastern red-cedar (Juniperus virginiana) tree.  Unlike the terrifyingly aggressive prairie rattlesnakes I encountered in South Dakota last fall, this snake seem to be relying upon its cryptic coloration to avoid detection, rattling only after I had approached quite closely… or maybe it was only then I could actually hear the rattle, which was barely audible and sounded much like the buzz of a small katydid.

Pygmy rattlesnakes are the smallest rattlesnakes in North America, growing to around 15-25 inches long – this individual looked to be about 18-20 inches in length.  They are one of only two U.S. species in the primitive rattlesnake genus Sistrurus – the other being the larger wet prairie inhabiting massasauga (S. catenatus).  All other rattlesnakes (28 species, 13 in the U.S.) belong to the genus Crotalus (Smith et al. 2001).  Western pygmy rattlesnakes are not really a western U.S. species, but rather the westernmost subspecies of this southeastern U.S. species (with subspecies miliarius and streckeri occupying the northeastern and southeastern portions, respectively, of its range).  In Missouri, it is not nearly as common as the timber rattlesnake (Crotalus horridus), occurring only in the extreme southern Ozarks along the border with Arkansas and up into the St. Francois Mountains of the eastern Ozarks (Johnson 1997).  Although no known human deaths have ever been caused by this species, known locally as the “ground rattler,” it is nevertheless poisonous and worthy of respect.  I must admit to having been lulled a little bit by its calmness – much like the juvenile copperhead I photographed in May – and found myself tempted to approach ever closer for photographs.  The photograph below represents the closest that I was able to get before it began “striking” at me – whether these were bluff strikes intended to frighten or actual attempts to bite I do not know.  Suffice it to say that I “got the message” and ended my attempts to get even closer.  Daughter Madison watched in nervous amazement as all this was going on, and afterwards I tried to impress upon her young, virgin mind what a rare and wonderful experience we’d just had.  Perhaps I succeeded, as this was the first story she told to her head-shaking mother upon our return home the following evening!

IMG_1016_1200x800

Photo details: Canon 100mm macro lens on Canon EOS 50D, ISO 100, 1/250 sec, f/9-10, MT-24EX flash 1/2 power through diffuser caps.

REFERENCES:

Johnson, T. R. 1997. The Amphibians and Reptiles of Missouri. Missouri Department of Conservation, Jefferson City, 368 pp.

Smith, H. M., E. D. Brodie, D. M. Dennis and S. Barlowe. 2001. Reptiles of North America: A Guide to Field Identification. Golden Field Guide from St. Martin’s Press, New York, 240 pp.

Copyright © Ted C. MacRae 2009

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Friday flower – Sabatia angularis

/ Ted C. MacRae / 19 Comments
Photo details: Canon 100mm macro lens on Canon EOS 50D, ISO 100, 1/60 sec, f/22, MT-24EX flash 1/4 power w/ diffuser caps.

Photo details: Canon 100mm macro lens on Canon EOS 50D, ISO 100, 1/60 sec, f/22, MT-24EX flash 1/4 power w/ diffuser caps.

During my explorations of the glades in the White River Hills in southwestern Missouri this past July, I noticed large populations of a flower that I couldn’t recall having ever seen before.  Vivid, striking pink petals with contrasting yellow anthers and a curiously recurved style, it seemed difficult to believe that I had simply overlooked it during my many previous visits to the area over the past 25 years.  Perhaps it was the time of year – I’ve generally avoided these glades during the month of July – normally hot, dry, and baked to a crisp.  This year and the last, however, have been different, with timely rains resulting in unusually lush July vegetation.  I also had no clue as to the identity of the plant – the square stems and opposite branching suggested a mint of some kind, but the flowers were definitely not “minty.”  I would have to simply take photographs and hope that I captured enough key characters to allow its identification once I returned home.

As it turns out, I was able to easily identify the plant as Sabatia angularis¹ (rose pink, rose gentian) using the late Dan Tenaglia’s excellent Missouri Plants website, and I wasn’t the only person to notice an apparent population explosion of this beautiful species across the Missouri Ozarks (see Justin Thomas’ excellent essay, A Sabatia Induced Rant).  As suggested by the common name, this species is in the family Gentianaceae, but it doesn’t resemble other gentians in general appearance, especially the iconic Gentianopsis crinita (greater fringed gentian) and, closer to home, Gentiana puberulenta (downy gentian), that usually come to mind upon mention of this plant family.

¹ Sabatia, for Liberato Sabbati, an 18th Century Italian botanist; angularis, Latin for angular, referring to the angled stem.

This plant occurs in the eastern U.S. west to Wisconsin in the north and Texas in the south.  Denison (1978) and Kurz (1999) both mention a preference by this species for acid soils, usually in rocky open woods, glades, old fields, and upland ridges – habitats which occur primarily across southern Missouri.  The opposite pattern of branching distinguishes this species from the alternately branched, somewhat smaller, and much less commonly encountered S. campestris (prairie rose gentian), which is most commonly encountered in the unglaciated plains of west-central Missouri.

These plants were common throughout the many glades that I visited during my two trips to the White River Hills in July, adding a vibrant splash of color to the glades after most of the other flowering plants found in these habitats have long flowered out and contrasting beautifully against the green background of uncommonly lush July grasses.

REFERENCES:

Denison, E.  1978.  Missouri Wildflowers.  A Field Guide to Wildflowers of Missouri and Adjacent Areas, 3rd revised edition.  Missouri Department of Conservation, Jefferson City, 286 pp.

Kurz, D.  1999.  Ozark Wildflowers.  A Field Guide.  Globe Pequot Press, Guilford, Connecticutt, 262 pp.

Copyright © Ted C. MacRae 2009

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North America’s longest insect

/ Ted C. MacRae / 26 Comments

This past June might be the most successful month entomologically that I’ve ever had.  The excitement of discovering a robust population of Cylindera celeripes (swift tiger beetle) (previously considered one of North America’s rarest tiger beetles) in northwestern Oklahoma lasted only two weeks before being eclipsed by our long-awaited success at finding this same species also in Missouri.  Icing on the cake was provided by finding Ellipsoptera macra (sandy stream tiger beetle) – the last tiger beetle species we had yet to encounter in Missouri, and significant new records for the tiny prairie cicada, Beameria venosa, and the impressive robber fly, Ospriocerus abdominalis, in Missouri’s critically imperiled loess hilltop prairies.  With that rapid-succession-success, my thoughts immediately turned to another of Missouri’s unique natural communities – the dolomite glades of the White River Hills in the extreme southwestern part of the state.  In fact, I had already been yearning to return to the White River Hills, having last visited some years ago and recalling – from the perspective now as an insect photographer – the many photogenic insect species that I’ve encountered there.  Chief among them is Plinthocoelium suaveolens (bumelia borer), a spectacularly beautiful longhorned beetle of neotropical affinity that must be seen to be believed and which I had observed here several years ago in fair numbers as they perched on the lower trunks of their presumed larval host, Sideroxylon (= Bumelia) lanuginosa of the family Sapotaceae.  I had even mentioned to my colleague Chris Brown, as we began the first day of our planned multi-weekend search for C. celeripes and C. macra in northwestern Missouri, that my dream scenario was that we would find both celeripes and macra on that first weekend, negating the need for additional survey the following weekends, in which case we could shoot down to the White River Hills to look for Plinthocoelium.  Who knew how prescient that comment would be!

Megaphasma denticrus - giant walkingstick

Megaphasma denticrus - giant walkingstick

I won’t keep you in suspense – I succeeded in finding and photographing Plinthocoelium, although (happily) there is more to the story than just that.  I’ll share that experience here soon, but first I want to discuss another insect I saw on the first of my two July visits to the White River Hills – Megaphasma denticrus¹ (giant walkingstick).  As implied by its common name, this walkingstick is enormous – females (typically larger than males) can reach lengths of 150+ mm (that’s 6 inches, folks!), making it officially the longest insect species in all of North America.  IMG_0909_1200x800The female I feature here was solidly in that range, and with her front legs held outstretched in front of her (as pictured above), total length exceeded 8 inches.  Of course, this pales in comparison to a related species from Borneo, individuals of which have been documented measuring more than 18 inches in length!  The giant walkingstick is distributed primarily in the south-central U.S. – especially Texas, although records do exist from as far north and east as Iowa, Wisconsin, and Indiana (Arment 2005). I have encountered this species a few times before – always in the White River Hills, but Arment (2005) also records the species from several other counties in the Ozark Highlands across southern Missouri and Arkansas.  In addition to its great size, both sexes of this species can be distinguished from other walkingsticks by the rows of numerous teeth on the underside of the middle (meso-) femur (easily seen in the enlarged view of Photo 2 above) and by the very long antennae (longer than the front femur).  Color is variable – other individuals I have seen are tan with bright red dorsal stripes on the thoracic segments.

¹ Formerly classified with grasshoppers and their kin in the order Orthoptera, walkingsticks are now placed their own order, Phasmatodea, the name being derived from the Greek phasma (apparition, ghost) in reference to their cryptic appearance and behavior (the alternative spellings Phasmodea and Phasmida are improper formations from the Greek root – see Grimaldi and Engel 2005).  The genus name, Megaphasma, thus means “giant walkingstick.”  The specific epithet, denticrus, is derived from the Latin den (tooth) and crus (leg), presumably a reference to the toothed underside of the mesofemur. Many authors, including even some taxonomists (e.g., Beamer 1932), have mispelled the name as “dentricus” – nonsensical in Latin – with some even using both spellings in the same paper (e.g., Maginnis et al. 2008)!

Of course, an outstanding feature of this species, and all walkingsticks in general, is its uncanny resemblance to sticks and twigs.  This cryptic appearance is further augmented behaviorally by the habit of “swaying” back and forth to simulate movement in a gentle breeze.  I must confess that I did not even notice this large female individual – less than two feet away on a low branch – until she started moving about.  Once spotted, a walkingstick of this size would seem to be a tasty – and defenseless – morsel for some avian predator; however, they have another defensive tactic up their sleeve – autotomy (i.e., the ability to shed appendages in response to predatory attack). IMG_0913_1200x800While it may seem that their long, delicate-looking legs are simply “pulled off” by the predator, fortuitously allowing the walkingstick to clamber to safety, leg shed is actually controlled by the central nervous system in response to external stimuli (e.g., grabbing of the leg).  Breakage occurs at predetermined abcission points, which are rapidly sealed after shedding to prevent excessive loss of body fluids.  I experienced this first hand – lacking any container large enough to hold the enormous female, I gently placed her into my net and gingerly carried her back to the truck, only to find a hind leg already shed by the time I got back.  I decided the effort to glue one (or more) legs in place to acheive a well-curated specimen exceeded my interest in starting a collection of this particular group of insects, so I let her go.  Presumably she crawled away to safety, though sadly no longer the ‘perfect’ specimen that I first encountered.

Photo details:
Photo 1 (full insect): Canon 100mm macro lens on Canon EOS 50D (auto mode), ISO 200, 1/320 sec, f/5.6, natural light.
Photos 2 (midrange) and 3 (closeup): same except (manual mode), ISO 100, 1/60 (Photo 2) or 1/250 (Photo 3) sec, f/10 (Photo 2) or f/20 (Photo 3), MT-24EX flash 1/4 power w/ diffuser caps.

REFERENCES:

Arment, C. 2005. Stick Insects of the Continental United States and Canada: Species and Early Studies. Coachwhip Publications, Landisville, Pennsylvania, 202 pp.

Beamer, R. H. 1932. The giant walking-stick (Megaphasma dentricus (Stal.)) found in Kansas. Journal of the Kansas Entomological Society 5(1):28.

Grimaldi, D. and M. S. Engel. 2005. Evolution of the Insects. Cambridge University Press, New York, xv + 755 pp.

Maginnis, T. L., Cool, C. L. and J. L. Muniz. 2008. Some observations on the mating behavior of the giant walkingstick, Megaphasma dentricus (Orthoptera: Phasmidae). Texas Journal of Science 60(1):57-62.

Copyright © Ted C. MacRae 2009

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Ospriocerus abdominalis

/ Ted C. MacRae / 18 Comments
Photo details: Canon 100mm macro lens on Canon EOS 50D, ISO 100, 1/250 sec, f/14, MT-24EX flash 1/4 power w/ diffuser caps.

Photo details: Canon 100mm macro lens on Canon EOS 50D, ISO 100, 1/250 sec, f/14, MT-24EX flash 1/4 power w/ diffuser caps.

My dipteran digression continues with this photograph of the robber fly, Ospriocerus abdominalis (Diptera: Asilidae).  More than just a pretty picture, this represents yet another apparently new state record that I and my colleague Chris Brown discovered a few weeks ago during our 2-day survey of Missouri’s critically imperiled hilltop prairies in the extreme northwest corner of the state.  Like the previously discussed Cylindera celeripes (swift tiger beetle) and Beameria venosa (a prairie-obligate species of cicada), O. abdominalis has not previously been recorded further east than Nebraska, Kansas, Oklahoma and Texas. This large fly is a grassland denizen that ranges over western North America and into Mexico (Cannings 1998, as Ospriocerus aeacus). It is somewhat suggestive of a mydas fly, although its short antennae immediately identify it as a robber fly (mydas flies have elongate clubbed antennae).  It also reminds me of the magnificent western robber fly Wyliea mydas by its mimetic, wasp-like coloration – presumably modeled after spider wasps of the genus Pepsis and Hemipepsis (Hymenoptera: Pompilidae) – but is distinguished by its black body and wings with red dorsal coloration on the abdomen (W. mydas has the abdomen wholly black and the wings red).  While not quite as handsome as W. mydas, it is impressive nonetheless.

The dry hilltop prairie remnants in which O. abdominalis, B. venosa, and C. celeripes were found are associated with the Loess Hills, a unique landform along the western edge of Iowa that reaches its southern terminus in extreme northwest Missouri.  Due to their extreme rarity and vulnerability to woody encroachment and anthropogenic degradation, these remnant habitats are considered one of Missouri’s most critically imperiled natural communities. Only about 50 acres of original habitat remain, and of this only half is in public conservation ownership.  Many of the plants and animals found in these habitats represent hypsithermal relicts that migrated eastward during a dry and warm period after the last ice age and were then “left behind” in pockets of relictual habitat as a return to cooler, wetter conditions forced the main populations back to the west.  More than a dozen plants and two vertebrates occurring in these prairies are listed as species of conservation concern.  As is typically the case, the flora and vertebrate fauna of these remnant habitats have been fairly well characterized, while precious little attention has been given to the vastly more diverse invertebrate fauna.  As we begin to study the insects of these habitats more carefully, we are almost sure to find a great many species that are more typically found further to the west and that live nowhere else in Missouri.  Their continued presence in the state will be wholly dependent upon the critically imperiled habitats in which they live, making conservation and restoration of the remaining loess hilltop prairie remnants in Missouri all the more important.

My thanks to Eric Fisher and Herschel Raney for confirming the identity of O. abdominalis.

REFERENCES:

Cannings, R. A. 1998. Robber Flies (Insecta: Diptera: Asilidae), in Smith, I. M., and G. G. E. Scudder, eds. Assessment of species diversity in the Montane Cordillera Ecozone. Burlington: Ecological Monitoring and Assessment Network.

Copyright © Ted C. MacRae 2009

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Overlooked, needle-tailed, thick-headed fly

/ Ted C. MacRae / 10 Comments
Photo details: Canon 100mm macro lens on Canon EOS 50D, ISO 100, 1/250 sec, f/16, MT-24EX flash 1/4 power w/ diffuser caps.

Photo details: Canon 100mm macro lens on Canon EOS 50D, ISO 100, 1/250 sec, f/16, MT-24EX flash 1/4 power w/ diffuser caps.

While photographing the rare Typocerus deceptus on flowers of wild hydrangea (Hydrangea arborescens) at Trail of Tears State Park in southeast Missouri last June, I encountered this strange fly also visiting the hydrangea blossoms.  At first I thought it was some weird type of syrphid fly, but it turns out to be a member of an even more unusual group of flies in the appropriately-named genus Stylogaster¹.  Although classified in the family Conopidae (thick-headed flies), members of this genus are placed in their own subfamily (Stylogastrinae) due to their unusual morphology and biology (obligate parasites of crickets, cockroaches and calyptrate flies).  Ninty-two described species are currently placed in the genus, only two of which occur in North America (the remainder are found chiefly in the Neotropics and in sub-Saharan Africa and southeast Asia).  This individual appears to be a female S. neglecta because of its short 2nd antennomere (antennal segment) and highly elongate 3rd antennomere (in S. biannulata, the 2nd antennomere is almost as long as the 3rd). Thus, the “overlooked, needle-tailed, thick-headed fly” – and who said common names are easier?

¹ Derived from the Latin stilus (needle) and the Greek γαστηρ (belly, stomach), a reference to the highly elongated female abdomen, or “tail.”

Morphologically, stylogastrines are distinguished from other conopids by their eggs, which feature a rigid barbed tip.  This, along with some behavioral observations, seems to imply a shooting oviposition technique; however, morphological evidence suggests that the eggs are forcibly jabbed into their hosts (Kotrba 1997).  The larvae hatch and develop inside their host as internal parasites, but other than the egg very little is known about the life histories of species in this genus (Couri and Pont 2006).  Adults are further distinguished by their long proboscis, which exceeds the length of the body when fully extended and is used to access nectar within a variety of flowers.  Adult females aggressively intercept hosts in-flight for oviposition, and speculation has been made that they are obligate associates of army ants (New World subfamily Ecitoninae and Old World subfamily Dorylinae), relying upon the ants’ raiding columns to flush out their prey.  However, since the genus also occurs in Madagascar and parts of Africa where army ants are completely absent, it is clear that at least some species of Stylogaster have no obligatory association with these ants (Stuckenberg 1963, Couri and Pont 2006).

REFERENCES:

Couri, M. S. and A. C. Pont. 2006. Eggs of Stylogaster Macquart (Diptera: Conopidae) on Madagascan Muscids (Diptera: Muscidae). Proceedings of the California Academy of Science 57(16):473-478.

Kotrba, M. 1997. Shoot or stab? Morphological evidence on the unresolved oviposition techique in Stylogaster Macquart (Diptera: Conopidae), including discussion of behavioral observations. Proceedings of the Entomological Society of Washington 99:613-621.

Stuckenberg, B. R.  1963.  A study on the biology of the genus Stylogaster, with the description of a new species from Madagascar.  Revue de Zoologie et Botaniques Africaines 68:251-275.

Copyright © Ted C. MacRae 2009

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The last tiger beetle

/ Ted C. MacRae / 22 Comments

Our recent discovery of Cylindera celeripes (swift tiger beetle) in Missouri was arguably the most exciting moment that I and colleague/fieldmate Chris Brown have experienced since we first began surveying the tiger beetles of Missouri back in the year 2000.  It was the 24th species that we had recorded for the state and the latest of several for which we had searched through targeted surveys during the past few seasons.  Earlier surveys have already produced a new record for Cicindela trifasciata ascendens (ascendant tiger beetle), “rediscovered” Cylindera cursitans (ant-like tiger beetle) and Dromochorus pruinina (frosted dromo tiger beetle), precisely characterized the limited in-state distributions of Habroscelimorpha circumpicta johnsonii (Johnson’s tiger beetle) and Cicindela obsoleta vulturina (prairie tiger beetle), and generated copious distributional data for the remaining more generally distributed species.

Yet, there still remained one species that we had not managed to find ourselves – Ellipsoptera macra (sandy stream tiger beetle).  This species was recorded from a few localities along the Missouri River in northwestern Missouri by Willis (1967), and we have examined a small number of additional specimens in the Enns Entomology Museum.  According to the literature, this species occurs near the water’s edge on sandy habitats along large rivers – precisely the type of habitats in which we have encountered the closely related E. cuprascens (coppery tiger beetle), which we have found at several locations along the Missouri and Mississippi Rivers.  Each time we found E. cuprascens we expected/hoped to see E. macra as well but never did.  The reasons for this remained a mystery to us until I noted a comment on the Tiger Beetles of Nebraska website stating that blacklighting is usually more productive for this species than daytime collecting.  With its known occurrence in northwestern Missouri, our planned survey for C. celeripes in that part of the state this season offered a perfect opportunity to try to find this, the last tiger beetle species in Missouri that we had not yet collected ourselves.  Our plan was to search loess hilltop prairie habitats during the day for C. celeripes, then blacklight along the Missouri River at night to look for E. macra.  Both species seemed like longshots – we’d searched for each many times, and we were willing to spend several consecutive weekends from late June to mid-July on our survey so that we could claim that we had given it our best shot.  Of course, as you know, we succeeded in finding C. celeripes on the first day of our first weekend, and we would also enjoy the same success with E. macra later that evening.

Chris Brown looks for Ellipsoptera macra amongst the swarm.

Chris Brown braves the swarm to look for individuals of Ellipsoptera macra.

We setup two blacklights at a public fishing access along the Missouri River (explaining to some puzzled locals exactly what we were doing and why), turned the lights on, and sat back with pizza and merlot as we waited for things to start coming to the sheets.  We had been to this site before in previous years and found E. cuprascens here, suggesting that suitable habitat was present in the area.  Almost immediately a growing cloud of all manner of aquatic insects began swarming around the lights, landing on the sheets – and flying down our shirts and in our hair whenever we tried to approach!  I don’t blacklight as much as I did in my younger days, but even then I wasn’t much of a fan of blacklighting near water for precisely these reasons.  We hadn’t had the lights going for more than 15 minutes or so before we saw the first tiger beetle crawling on the bottom of the sheet below the light.  It looked like cuprascens, but I placed it live in a vial anyway for photographs the next morning.  Then there was another… and another…  Soon, they were coming in with regularity, and I quickly ran out of vials in which to keep live individuals separately.  I’ve never seen tiger beetles come to blacklights like this, but we still weren’t convinced they were E. macra until later that night when we got back to the hotel and had a chance to take a close look at them with good light.  There was no doubt about it – we had finally found E. macra in Missouri!

This species is very similar to E. cuprascens, but the elytra are not as shiny and with smaller, shallower punctures than the latter.  Some references mention a more recurved lower portion of the humeral lunule and a generally more green than bronze coloration (Pearson et al. 2006), but these characters were tenous at best with the specimens we had in hand (see photo below).  The best character we have found to separate the two species is by examining the female elytra – in E. macra the sutural apex is acute, while in E. cuprascens it is rounded (Willis 1967).  We returned to the site the next morning to see if we could find them during the day, and although we did manage to find a few, they were nowhere near as numerous as we had seen them at the blacklights the night before.  The following photograph is of an individual captured that evening and then “released” back into the field the following morning – they were quick to fly once released, and only after several individuals and trying the “lens cap” technique did we succeed in getting some good shots.

Ellipsoptera macra

Ellipsoptera macra

We didn’t get a chance to use blacklights in subsequent weekends to see if we could find E. macra in other localities along the Missouri and Mississippi Rivers – with E. macra and C. celeripes success already in hand, I quickly turned my attention to the White River Hills of southwestern Missouri and their gorgeous glade habitats to look for one of North America’s most beautiful cerambycid beetles, Plinthocoelium suaveolens (more on that in a future post).  However, I am confident that E. macra will be found at other spots in Missouri should we decide to look for them with blacklights.  Having encountered all 24 species of tiger beetles known from Missouri, I present here a checklist of those species.

CHECKLIST OF TIGER BEETLES IN MISSOURI
(classification and common names by Erwin and Pearson 2008)

Tribe CICINDELINI
Subtribe MEGACEPHALINA
Tetracha (s. str.) carolina carolina – Carolina Metallic Tiger Beetle
Tetracha (s. str.) virginica – Virginia Metallic Tiger Beetle

Subtribe CICINDELINA
Cicindela (s. str.) duodecimguttata – 12-spotted Tiger Beetle
Cicindela (s. str.) formosa generosa – Eastern Sand Tiger Beetle
Cicindela (s. str.) hirticollis shelfordi – Shelford’s Tiger Beetle
Cicindela (s. str.) limbalis – Common Claybank Tiger Beetle
Cicindela (s. str.) purpurea purpurea – Cowpath Tiger Beetle
Cicindela (s. str.) repanda – Bronzed Tiger Beetle
Cicindela (s. str.) scutellaris lecontei – LeConte’s Tiger Beetle
Cicindela (s. str.) sexguttata – Six-spotted Tiger Beetle
Cicindela (s. str.) splendida – Spendid Tiger Beetle
Cicindela (s. str.) tranquebarica tranquebarica – Oblique-lined Tiger Beetle
Cicindela (Cicindelidia) obsoleta vulturina – Prairie Tiger Beetle
Cicindela (Cicindelidia) punctulata punctulata – Punctured Tiger Beetle
Cicindela (Cicindelidia) rufiventris rufiventris – Eastern Red-bellied Tiger Beetle
Cicindela (Cicindelidia) trifasciata ascendens – Ascendant Tiger Beetle
Cylindera (s. str.) celeripes – Swift Tiger Beetle
Cylindera (s. str.) cursitans – Ant-like Tiger Beetle
Cylindera (s. str.) unipunctata – One-spotted Tiger Beetle
Dromochorus pruinina – Frosted Dromo Tiger Beetle
Ellipsoptera cuprascens – Coppery Tiger Beetle
Ellipsoptera lepida – Ghost Tiger Beetle
Ellipsoptera macra macra – Sandy Stream Tiger Beetle
Habroscelimorpha circumpicta johnsonii – Johnson’s Tiger Beetle

Photo details:
Blacklighting: Canon 17-85mm zoom lens on Canon EOS 50D (manual mode), ISO 100, 1/30 sec, f/11, on-camera flash.
Ellipsoptera macra: Canon 100mm macro lens on Canon EOS 50D (manual mode), ISO 100, 1/250 sec, f/14, MT-24EX flash 1/4 power w/ diffuser caps.

REFERENCES:

Erwin, T. L. and D. L. Pearson. 2008. A Treatise on the Western Hemisphere Caraboidea (Coleoptera). Their classification, distributions, and ways of life. Volume II (Carabidae-Nebriiformes 2-Cicindelitae). Pensoft Series Faunistica 84. Pensoft Publishers, Sofia, 400 pp.

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.

Willis, H. L.  1967. Bionomics and zoogeography of tiger beetles of saline habitats in the central United States (Coleoptera: Cicindelidae).  The University of Kansas Science Bulletin 47(5):145-313.

Copyright © Ted C. MacRae 2009

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