Done with dung, meat please!

ResearchBlogging.orgNo feces for this species.” “Carnivorous dung beetle shuns dung and decapitates millipede.” “Little dung beetle is big chopper.” “Dung beetle mistakes millipede for dung.” These were some of the clever headlines that I had to compete with in coming up with my own opener for a remarkable beetle that titillated the science blogosphere last week. At the risk of being redundant, I’d like to revisit that beetle and offer a few (hopefully novel) thoughts of my own. I can say that I have a unique and special treat for those willing to read further.

First the background. Deltochilum valgum is a so-called “dung beetle” in the family Scarabaeidae that lives in the lowland rain forests of Peru. As suggested by its common name, it belongs to a group of beetles that are well known for their dung feeding habits. Over 5,000 species of dung beetles are known throughout the world, all of which carve out balls of dung and bury them as provisions for larval development – or so it was thought.  As reported by Trond Larsen of Princeton University and colleagues in Biology Letters, D. valgum has apparently abandoned its ancestral dung ball-rolling behavior in favor of a predatory lifestyle. Its prey – millipedes! Moreover, the species exhibits several distinct morphological traits that appear to have evolved as a direct result of their predatory behavior. Adult beetles were repeatedly observed killing and eating millipedes, and their disdain for dung was rather conclusively demonstrated by an exhaustive, year-long trapping program in which pit-traps were baited with a variety of bait types known to attract dung beetles (e.g., various kinds of dung, carrion, fungus and fruit) – and millipedes.  In all, over 100,000 dung beetles representing 132 species were trapped (what a nice collection!), 35 of which were found to scavenge on dead millipedes, but only five of these dared tackle live millipedes.  Of these, only D. valgum ignored all other foods – it only came to traps baited with live millipedes.

Larsen et al. determined that adults of D. valgum are opportunistic hunters and were much more likely to attack injured millipedes than healthy ones, even those weighing 14 times as much as the beetle.  Ball rolling behavior was never observed by D. valgum.  Most dung beetles have wide, shovel-shaped heads used to scoop and mold dung balls, but D. valgum has a much narrower head with sharp “teeth” on its clypeus (Fig. 1A vs. 1B).  The teeth apparently aid in killing the millipede by piercing the ventral surface behind the head and prying upwards (decapitating it), and the narrow, elongate head facilitates insertion into the millipede body for feeding.  Further, the hind tibia are elongate and curved, which are used to “grip” millipedes by holding them up against the dorsally reflexed pygidium (Fig. 1C vs. 1D).  This allows the beetle to drag its coiled up victim with one hind leg while walking forward on the other five (Fig. 1E).  Once killed, the beetles proceeded to break their prey into pieces and consume their meaty innards, leaving the disarticulated millipede exoskeletons licked clean (Fig. 1F).  One of these “attack” episodes was filmed (using infrared lighting so as not to affect their nocturnal behavior) and can be seen in this BBC News video.

Deltochilum valgum

Figure 1. (a) Dorsal view of D. valgum head. Sharp clypeal teeth and angled clypeus act as a lever to disarticulate millipede. Narrow, elongate head permits feeding inside millipede; (b) dorsal view of Deltochilum peruanum head, lacking characters described in (a), head used to mould dung balls; (c) lateral view of D. valgum pygidium and hind tibia. Dorsally reflexed pygidial lip is used to support millipede during transport. Elongate, strongly curved hind tibia is used to grip millipede. (d ) Lateral view of D. peruanum pygidium and hind tibia, lacking characters described in (c), hind tibia used for rolling dung balls. (e, f ). Predation strategy by D. valgum. (e) Dragging live, coiled millipede with one hind leg, walking forwards; ( f ) feeding on killed millipede with head inside
segments; disarticulated empty millipede pieces nearby.
Credit: Larsen et al. (2009).

Much has been made about this remarkable shift from coprophagy to predation, which Larsen et al. speculate was driven by competition for limited resources with the many other dung beetle species that occur in the Peruvian rainforests. In fact, adult dung beetles are known to feed on a variety of resources besides dung, as exemplified by the range of baits used in their survey. Thus, my first thought after reading the coverage was actually a question: “Has this species abandoned dung provisioning completely as a reproductive strategy?” Everything I had read focused exclusively (quite understandably) on the bizarre feeding habits of the adults, but there was no mention of what the species’ larval provisioning strategies were. Wanting more information about this, I contacted Trond Larsen, who graciously sent me a PDF of the paper. Unfortunately (though not a criticism of the paper), no further insight about this was found in the paper either. Indeed, in all of the observations recorded by Larsen et al., millipedes killed by D. valgum were consumed entirely by the adults, and no mention was made of how or whether millipedes were utilized for larval provisioning. I wondered if D. valgum had truly abandoned dung provisioning for larval development (a remarkable adaptive switch), or if in fact the species might still utilize the strategy for reproduction (perhaps having specialized on a dung type not included in their survey), while also exploiting millipede predation as adults for a nutritional advantage. I asked Trond about this, to which he replied with this juicy tidbit (I told you I had a special treat!):

Yes, I would very much like to know what the reproductive/nesting behavior of D. valgum is. My best guess is that they also use millipedes as a larval food source, but as you say, we haven’t observed that behavior yet. I have observed other generalist dung beetle species rolling balls out of dead millipedes, presumably to bury for the larvae, so I certainly think it would be an adequate food source. Many dung beetle species use carrion for their larvae.

I am quite confident that D. valgum does not use any kind of dung. I have sampled these dung beetle communities very thoroughly, with many dung types and other bait types, and also with passive flight intercept traps that catch all beetles. Every dung beetle species that feeds on dung is at least sometimes attracted to human dung (this is not the case in African savannahs though, but is in neotropical forests – that is a whole different story). There are still a small handful of species we catch in flight intercept traps that we don’t know what they eat, although some of these mysteries have recently been solved – many of them live in leaf-cutter ant nests for example.

While predation of millipedes by a dung beetle is itself a fascinating observation, demonstrating the abandonment of dung provisioning in favor of captured prey for larval development would be a truly remarkable example of an ecological transition to exploit a dramatically atypical niche. I hope Trond (or anybody for that matter) actually succeeds in observing millipede/prey utilization for larval provisioning by this species.

Many thanks to Trond Larsen for his delightful correspondence.

SOURCE:
Larsen, T. H., A. Lopera, A. Forsyth and F. Génier. 2009. From coprophagy to predation: a dung beetle that kills millipedes. Biology Letters DOI: 10.1098/rsbl.2008.0654.

Copyright © Ted C. MacRae 2009

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl

Christmas in January

One of the ironies about collecting insects is that the winter months can be just as busy as the summer months, sometimes more so. Despite the lack of insect activity during these short, cold days, I actually find myself at times a little overwhelmed with the amount of “work” I’ve set myself up to do.  There are specimens to mount, label, curate, and incorporate into the main collection.  Data from the just concluded field season need to be assembled and summarized so that reports and manuscripts can be written.  Applications for collecting permits need to be submitted, which can only be done once plans for the upcoming season have been formulated.  The fact that entomology is also my profession only exacerbates the situation.  Not that I’m complaining!  I love the fact (and sometimes still have a hard time believing) that I actually get paid to play with bugs, which affords me the opportunity to study them as I wish in my free time.

hiperantha-interrogationis-cruentata_dorsal_21Hiperantha interrogationis cruentata (ventral)In addition to these winter tasks for my own collection, I’ve also for a number of years now taken on the task of identifying material for other collectors.  While this may seem very nice of me, I can’t honestly claim that my motives are completely altruistic.  Doing this has given me the chance to develop relationships with a great many entomologists, specializing in taxa both within and outside my sphere of interest.  Often, material sent to me contains specimens that represent new distributional or host plant records, providing fodder for my own research.  Less frequently but more exciting, such material will contain species that I haven’t yet encountered on my own.  In most cases, the sender will be gracious enough to let me keep an example or two for my collection.  Such is the case with this gorgeous buprestid beetle, Hiperantha interrogationis, which was included in a recent shipment to me as a “gift” from long time friend and expert cerambycid specialist Dan Heffern.  This Neotropical representative of the tribe Stigmoderini (which also contains the Australasian genera Calodema and Metaxymorpha, featured in this recent post) not only represents a new species for my collection, but a new genus as well (reminding me of the old adage, “some of the best collecting is in other people’s collections” – or something like that).  Measuring right at 25mm in length, this spectacularly beautiful specimen is a welcome addition to my collection!

Hiperantha interrogationis is the only member of this otherwise South American genus to occur as far north as Central America and Mexico (Bellamy 2008).  This particular specimen was collected in Jalisco, and as such represents the subspecies cruentata, occupying the northernmost portion (Colima, Durango, Jalisco, and Nayarit) of the distributional range of the species (Bellamy & Westcott 2000).  Hiperantha interrogationis cruentata is distinguished from nominotypical populations by having all of the dorsal color pattern in red (nominate H. interrogationis exhibit some yellow markings) and the median longitudinal vittae of the elytra widely interrupted, thereby resulting in the formation of a distinctly transverse postmedian band. The apical transverse band of the elytra is also usually much wider in this subspecies than in the nominate form.

In a familiar refrain, not much is known about H. interrogationis other than distributional records.  Adults have most often been encountered on flowers of tropical trees, but larval hosts are completely unknown.  Manley (1985) published observations on the feeding behavior of adults on flowers of “Niguito”, Muntingia calabura (Elaeocarpaceae) near Guayaquil, Ecuador.  The adults were observed to be rather strong, high fliers that hovered over flowers in the tops of the trees before alighting, often on the terminal flower of a high branch.  Adults were observed consuming the petals of the flowers but were never observed feeding on the foliage.  After consuming all the petals of a flower, a process that required around 20-30 minutes, the adults moved off to adjacent foliage to groom themselves or rest.  No adults were observed on flowers of any other plant species in this area, but Bellamy & Westcott (2000) later recorded both subspecies on flowers of Acacia angustissima (Fabaceae) and the nominate subspecies on flowers of Chilopsis linearis (Bignoniaceae).

My sincere thanks to Dan Heffern for giving me his single specimen of this gorgeous species.

REFERENCES:

Bellamy, C. L.  2008. World catalogue and bibliography of the jewel beetles (Coleoptera: Buprestoidea),  Volume 2: Chrysochroinae: Sphenopterini through Buprestinae: Stigmoderini.  Pensoft Series Faunistica 77: 632-1260.

Bellamy, C. L. and R. L. Westcott.  2000. The genus Hiperantha: subgenera, type species, unavailable names and the Mexican fauna (Coleoptera: Buprestidae).  Folia Heyrovskyana 8(1):25-34.

Manley, G. V.  1985. Notes on the biology of Hyperantha interrogationis Klug (Coleoptera: Buprestidae).  The Coleopterists Bulletin 39(1):16-17.

Copyright © Ted C. MacRae 2009

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl

Tyrant ground beetles

I return to my Afrikaans theme with a distinctive group of ground beetles (family Carabidae) called tyrant ground beetles or spotted ground beetles (tribe Anthiini). I think I prefer the former. This tribe is largely restricted to Africa and is especially diverse and abundant in the arid, sandy Karoo and Kalahari regions of southern Africa (Scholtz & Holm 1985). These beetles are large, powerful predators that rely on speed and agility for capturing prey, and since they are also flightless these characteristics come in handy for avoiding becoming prey themselves. Failing that, they employ chemical defense in the form of secretions from a pygidial gland located in the area of the ninth abdominal segment. The chemical cocktail within these secretions contains concentrated organic acids or quinone that can be squirted at potential predators in a strong jet. This is an effective deterrent to small mammalian and avian predators, and I suppose a careless beetle collector might also regret handling these beetles without due respect. These defensive spray capabilities give rise to another common name for the group, “oogpister” – an Afrikaner word that literally translates to (ahem) “eye pisser.”

Anthia (s. str.) thoracicaDuring my time in Africa, Chuck Bellamy and I were primarily focused on collecting buprestids. However, we still couldn’t resist hanging an ultraviolet light in front of a sheet and searching the ground with flashlights at night to see what diversity of other African insects we might encounter. Truth be told, one of the non-buprestid groups that I’d really hoped to encounter was a near relative of these beetles – the so-called “monster tiger beetles” of the genus Manticora (family Cicindelidae1). We never did see any monsters, but we did encounter several species of anthiine ground beetles around our encampment at Geelhoutbos farm near the Waterberg Range in Limpopo Provice. Anthia (s. str.) thoracica, the giant African ground beetle (above), was the most impressive of these. Click on the photo to see a larger version – only then will it begin to convey how truly appropriate such a common name is for this species. It is certainly the largest ground beetle that I have ever seen – a full 50 mm in length! That’s 2 inches, folks! This species is easily recognized by the depressed lateral expansions of the pronotum covered with dense white/yellow pubescence, and the slightly smaller male that I caught exhibits more elongated mandibles (though not so incredibly as in Manticora) and marvelous lobes extending backward from the pronotum.

1 Increasingly placed within the Carabidae as subfamily Cicindelinae on the basis of molecular phylogenetic analysis, along with Paussinae and Rhysodinae (e.g., Beutel et al. 2008).

Anthia (Termophilum) omoplataIn addition to true Anthia, we saw two species of the subgenus Anthia (Termophilum)2. The species shown right is A. (T.) omoplata3, with the common name “two-spotted ground beetle” (Picker et al. 2002). It was almost as large as its giant brother above, measuring 47 mm in length. Of this species, I only saw this one individual, but I did also find two individuals of a related species, T. fornasinii. Unfortunately I was unable to photograph the latter species, which is equally large but with the elytral white markings limited to a thin marginal band and the surface of the elytra bearing strong longitudinal intervals – a handsome beast, indeed! Picker et al. (2002) mention T. homoplatum being a diurnal hunter, but we found all of our anthiines active nocturnally.

2 Treated variously in the literature as either a full genus or as a subgenus of Anthia. I follow Carabidae of the World, in which it is given subgeneric status. The name is often cited as “Thermophilum” in the literature, but this is an incorrect subsequent spelling according to Alexandre Anischenko (in litt.), coordinator/editor of Carabidae of the World.

3 Usually cited as “homoplatum” or “homoplata” in the literature, but this is an incorrect subsequent spelling (Anischenko in litt.).

cypholoba-alveolataA second genus in the tribe is Cypholoba, represented here by C. alveolata. As far as I can tell it lacks a common name, which is not surprising since it is somewhat smaller than the Anthia species mentioned above. Still, my two specimens measure 38 and 35 mm in length – not puny by any standard. There can be no doubt as to the origin of the specific epithet of this species’ scientific name, with its marvelously alveolate elytra. I don’t think I’ve seen such an extraordinary example of this type of surface sculpturing on a beetle of this size, making the species every bit as spectacular as the larger anthiines.

A truly fascinating aspect of Africa’s tyrant ground beetles is their role as models in Batesian mimicry systems. That these beetles should serve as models is not at all surprising due to their chemical defensive capabilities and obviously aposematic coloration. What is surprising is the mimic – juveniles of the lizard species, Eremias lugubris, in what is believed to be the first reported case of a terrestrial vertebrate mimicking an invertebrate (Huey & Pianka 1977). The juveniles not only copy (roughly) the black and white coloration of anthiine beetles but also mimic their rapid, skitty movements – foraging actively with “jerky” motions and arched backs. Their tails remain somber colored, however, allowing them to blend into the sand. These adaptations combine to give the harmless little lizard the size, color, profile, and gait of the beetles. As the lizards reach adulthood (and their greater size makes them less prone to predation), they take on a more typical cryptic coloration and move in a slower, more deliberately lizard-like manner. This mimicry association effectively reduces predation of the juveniles by potential predators, who quickly learn to avoid the noxious, and more frequently encountered, anthiine models.

REFERENCES:

Beutela, R. G., I. Riberab and O. R. P. Bininda-Emonds. 2008. A genus-level supertree of Adephaga (Coleoptera). Organisms, Diversity & Evolution, 7:255–269.

Huey, R. B. and B. R. Pianka. 1977. Natural selection for juvenile lizards mimicking noxious beetles. Science, 195 (4274):201-203.

Picker, M., C. Griffiths and A. Weaving. 2002. Field Guide to Insects of South Africa. Struik Publishers, Cape Town, 444 pp.

Scholtz, C. H. and E. Holm (eds.). 1985. Insects of Southern Africa. Butterworths, Durbin, 502 pp.

Review of Calodema and Metaxymorpha

ResearchBlogging.orgNylander 2008Insects are not only the most diverse group of animals in the world, they are also among the most beautiful.  Beetles, of course (with apologies to any lepidopterists that may be reading this), are responsible for a hefty slice of this majestic diversity, with the most spectacular of these belonging primarily to a few select families.  Longhorned beetles, who combine vibrant colors with grossly elongated antennae and legs.  Scarabs, upping the anty by sporting a monstrously wonderful array of horns or just sheer size to go along with their bright colors.  Tiger beetles, whose elaborate designs and vivid colors are further augmented with toothy-jawed, behavioral charisma.  Yet, it is the Buprestidae upon which the moniker “jewel beetles” has been bestowed, despite their lack of obvious morphological gimmicks – a testament to their bright, sparkling, even gaudy colors and exquisite surface sculpture.

Calodema spp.Some of the most beautiful buprestids in the world are found in the rainforests of southeast Asia, Indonesia, New Guinea and northern Australia.  Genera such as Catoxantha, Chysochroa, Megaloxantha, and Chrysodema come to mind – big, beautiful beetles with screaming iridescence of green, red, yellow and blue.  Living jewels!  These and related genera comprise the great tribe Chrysochroini – the “classic” jewel beetles.  Not as well known but perhaps even more spectacular than the chrysochroines are two genera with strictly Australasian affinities – Calodema (left) and Metaxymorpha (below).  These two genera are the subject of a review authored by Swedish entomologist Ulf Nylander and published in the journal Folia Heyrovskyana by Kabourek.  This gorgeously printed, copiously illustrated, and handsomly bound volume is as much a work of art as it is a technical review.

Metaxymorpha spp.Calodema and Metaxymorpha are among several genera comprising the tribe Stigmoderini in the subfamily Buprestinae.  Six genera, including Calodema and Metaxymorpha, are strictly Australasian, while another five genera are of southern Neotropical occurrence.  This now-disjunct tribal distribution suggests an origin on Gondwana prior to its break up beginning about 167 million years ago during the mid-Jurassic.  Calodema and Metaxymorpha are restricted to New Guinea and its associated islands and the northern and northeastern coastal areas of Australia.  The two genera share certain features that distinguish them from other stigmoderines, notably elongated mouthparts adapted to feeding on nectar and a streamlined, aerodynamically-shaped body with the prosternum (ventral sclerite behind the head) curiously prolonged into a large conical process.  Nylander discusses the possible function of this process in serving as a ballast to help stabilize the flight of these large beetles as they fly through branches and other obstructions in the upper forest canopy searching for flowers on which to feed.  This thought is based on the observation that adult beetles dropped from any angle are able to quickly right themselves and fly away before hitting the ground, while stigmoderines in other Calodema ribbeigenera – lacking the prosternal process – more often drop to the ground and feign death (presumably an adaptation for predator avoidance in the more open environments where they occur).  Calodema and Metaxymorpha are clearly related to each other but are distinguished by the smaller scutellum and nonoverlapping elytra of Calodema versus larger scutellum and distinctly overlapping elytra (in the apical area, usually left over right) of Metaxymorpha.

Fifteen species of Calodema and 18 species of Metaxymorpha are recognized, with comparative tables, figures, and keys provided to differentiate the species and species groups within each genus.  Four species are described as new, including Calodema hanloni, C. longitarsis and Metaxymorpha alexanderiensis from Papua New Guinea, and M. hanloni from Australia.  Species treatments include synonymies, information on type specimens and type localities, label data for specimens examined, detailed descriptions, and comments on distribution and flight periods when known.  Metaxymorpha nigrofasciataHigh quality, full color photographs are provided for every species.  In many cases, multiple specimens are illustrated to show the degree of intraspecific variation encountered in the specimens studied, as shown in the examples included here for Calodema ribbei (above) and Metaxymorpha nigrofasciata (right).  These fabulous plates would almost be enough to justify ‘coffee table book’ status, were it not for the decidedly technical nature of the text itself.  Lest you think this makes for a strictly dry read, there are additional comments for several species regarding historical localities and collection circumstances.  One of the more fascinating is this passage for Calodema vicksoni from Papua New Guinea:

The holotype was captured by a native lady who found this specimen feeding on flowers near her house in the jungle in a very remote location in the Owen Stanley Range.  She caught the beetle and gave it to her husband.  Sadly enough, shortly afterwards she was bitten by a Papuan Blacksnake and died.

The morbid origins of this species become even more gruesome, as Nylander further explains that the species was named to honor the memory of the late Vickson Kotaseao – an associate at the Wei Institute in Papua New Guinea who was the first person to discover the larva of Calodema, and who was later brutally murdered in an ambush while on duty.  The book concludes with a summary of the meager biological information recorded for species of Calodema and Metaxymorpha, including observations of larvae presumed to be Calodema ribbei and their host tree.  As a special bonus, the book comes with a DVD that includes videosequences of adults of several species (Calodema regalis, C. blairi, C. ribbei, C. hudsoni, Metaxymorpha nigrosuturalis, and M. meeki) feeding on their flower hosts in the Australian and Guinean rain forests.  While the color photographs in the book are truly stunning, seeing these beetles on video emphasizes their true spectacularity as living, behavioral creatures and not just dead, pinned specimens.

This book is a beautiful assemblage of all that is currently known about some of the world’s most gorgeous beetles.  Sadly, it also emphasizes just how incomplete that knowlegde really is.  Of the 33 species now recognized in these two genera, 20 of them (60%) have been described in just the past 15 years, and virtually nothing is known of the biology of the vast majority of them.  Seven species are known from just a single specimen, and several more are known by only a very small handful.  In an age where advanced molecular genetic techniques offer great promise for unlocking stores of knowledge about evolutionary relationships among earth’s biota, Calodema and Metaxymorpha offer a sobering reminder that there is still much to do in the less glamorous world of alpha taxonomy.  As noted by Nylander, the center of diversity for these spectacular buprestids appears to be in the Papua New Guinea central highlands – primary rain forests that are increasingly threatened by both legal and illegal logging.  To destroy such a biodiversity “hotspot” would be a sad legacy to leave – but to destroy it without even knowing what was there to begin with would be simply shameful.

I thank Ulf Nylander for granting me permission to scan and post these gorgeous plates, representing but a few of the many beautiful illustrations that can be found in his book.

REFERENCE:

Nylander, U. (2008). Review of the genera Calodema and Metaxymorpha (Coleoptera: Buprestidae: Stigmoderini) Folia Heyrovskyana, Supplementum 13, 1-84.

Top Ten of 2008

For the first post of 2009, I begin with a look back at some of my favorite photos from 2008 (idea stolen from Alex Wild and others).  I initially hesitated to do a “best photos” post since I’m not really a photographer – just an entomologist with a camera.  Nevertheless, and with that caveat in mind, I offer ten photos that represent some of my favorites from this past year. To force some diversity in my picks, I’ve created “winning” categories (otherwise you might just see ten tiger beetles!). Click on the photos to see larger versions, and feel free to vote for your favorite. If so, what did you like about it? Was there a photo I didn’t pick that you liked better?  Enjoy!

Best tiger beetle

Cicindela formosa generosa

From “All the better to see you with, my dear!” (September 2008).  Picking a top tiger beetle photo was tough with so many to choose from.  Ultimately, I decided I really like these face-on shots, and of the several I’ve posted this one of Cicindela formosa generosa has the overall best composition, balance and symmetry.  I considered this one of Cicindela formosa formosa – with its half-cocked jaws, it probably has better personality.  However, the one above got the final nod because it is a true field shot of an unconfined, unmanipulated individual.

Best jewel beetle

Aegelia petelii

From Buppies in the bush(veld) (December 2008).  Although taken back in 1999, I just recently scanned and posted this photo of Agelia petelii from South Africa.  I like the bold, contrasting colors of the beetle combined with the soft colors of the host foliage.  Runners up included these photos of Evides pubiventris with its sumptuous iridescent green blending beautifully with the green background (but suffering slightly from shallow depth of field) and Chrysobothris femorata with its intricate surface sculpturing.

Best longhorned beetle

Tetraopes femoratus

From Rattled in the Black Hills (September 2008).  This was an easy choice – none of the other longhorned beetle photos that I posted during 2008 matched this photo of Tetraopes femoratus for clarity, composition, and the striking contrast between the red color of the beetle and the green color of the host plant.  I especially like the detailing of the body pubescence.

Best non-beetle insect

Proctacanthus milbertii

From Magnificently Monstrous Muscomorphs (November 2008).  I do like other insect besides beetles, and robber flies are hard to beat for their charisma.  This photo of Proctacanthus milbertii (which, as Chris Taylor pointed out, literally translates to “Milbert’s spiny butt”), has great composition and nice, complimentary colors.  I like contrast between the fine detail of the fly and the soft background.

Best non-insect arthropod

Argiope aurantia

From Happy Halloween! (October 2008). I didn’t have many non-insect arthropod photos to choose from, but this photo of a female Argiope aurantia (yellow garden spider) would be deserving of recognition no matter how many I had to choose from. I like the bold, contrasting colors and symmetry of the spider in front of the dappled background of this photo.

Best non-arthropod animal

Prairie rattlesnake (Crotolus viridis)

Another one from Rattled in the Black Hills (September 2008).  This is admittedly not the best photo from a purely technical perspective – it’s a little out of focus, and the color is a bit off.  However, no photo could better convey the moment – confronted with a live, angry prairie rattlesnake (Crotalus viridis) (among the more aggressive species in the genus).  The forked tongue and rattle – blurred in motion – were icing on the cake.

Best wildflower

Victoria Glades

From Glades of Jefferson County (July 2008).  I had several wildflower closeups to choose from, but I kept coming back to this field shot of pale purple coneflower (Echincea simulata) and Missouri evening primrose (Oenethera macrocarpa).  The eastern redcedars (Juniperus virginiana) in the background are at once indicative of their preferred habitat (limestone/dolomite glades) and also testament to their threatening encroachment.

Best tree

Calocedrus decurrens

From the very simply and aptly named Lake Tahoe, California (March 2008).  Incense cedar (Calocedrus decurrens), with its reddish, deeply furrowed bark and great height, is one of the most majestic of western conifers.  I was captivated by this tree – beautiful even in death and contrasting nicely with the surrounding green foliage.

Best rockscape

Pipestone National Monument, Old Stone Face

From Pipestone National Monument (April 2008).  “Old Stone Face” is one of Pipestone’s most recognizable geologic features, and the short angle of the sun on this early spring day provided nice detail to the cracks and fissures of the rock – almost appropriately adding a weathered “age” to this old man.

Best landscape

Emerald Isle, Lake Tahoe

Another one from Lake Tahoe, California (March 2008).  Few places on earth are more photogenic than Lake Tahoe, and this perspective overlooking Emerald Bay is among the finest views I’ve seen.  Brilliant blue skies and majestic snow covered mountains reflected perfectly from the still surface, with Fannette Island providing a perfect focal point for the photo.

Best miscellaneous

Water drops, Ozark Trail, Trace Creek SectionFrom Ozark Trail, lower Trace Creek Section (December 2007).  While technically not a 2008 photo, it’s close enough.  This was one of the first macro photographs I took with my camera, and it remains one of my favorites.  A chance occurence of an unlikely subject, created by cold temperatures and heavy moisture-laden air. I like the contrast between the water drops – sharp, round, and clear – with the vertical shapes of the leaf petioles and background trees.  Viewing the image full-sized reveals the reflection of the photographer in the leftmost water drop.

Subsequent edit: Okay, so after I put this post together, I realized I actually featured eleven photos – too much difficulty choosing, I guess. Let’s call it a baker’s ten.

Cicindela lengi vs. Cicindela formosa

Back to beetle blogging – I hope everyone enjoyed their holiday break as much as I. One of the tiger beetles that I most hoped to see on my trip to Nebraska and South Dakota last September was Cicindela lengi (blowout tiger beetle). This is another one of the several tiger beetle species confined to dry sand habitats in the central/northern Great Plains (Pearson et al. 2006). Its common name would suggest it prefers sand blowouts, the most barren of dry sand habitats and where the co-occurring C. limbata (sandy tiger beetle) can be found. In reality, it also can be found in slightly more vegetated habitats such as dune margins, sand flats, and sandy roadsides along with the much more common C. formosa (big sand tiger beetle) and C. scutellaris (festive tiger beetle). It can also be found occasionally on sand bars along rivers, where the aptly-named C. lepida (ghost tiger beetle) is likely to occur, and in the northern part of its range it even inhabits boreal coniferous forest along sandy roadsides.

Cicindela lengi lengiDespite its relatively loose habitat requirements, C. lengi is not a common species. In Nebraska it may be locally abundant (Spomer et al. 2008), and while planning my trip I was fortunate to get a specific locality from Steve Spomer and Matt Brust for one of these localized populations in far northwestern Nebraska. [Happily, that locality was very close to the locality where I would be looking for another priority species for the trip, C. nebraskana (prairie long-lipped tiger beetle)]. The site – a sandy roadside embankment – was characterized by a very fine-grained sand, which Matt Brust tells me the species appears to favor over the coarser-grained sands more typical of the Sandhills to the east. Success did not come easily – when no adults were seen at the site after two consecutive days of searching, I hedged my bets and extracted larvae that I hoped would represent this species for an attempt at rearing them out to adulthood in the laboratory. Persistence paid off, however – a hunch told me to make one more visit to the site after a couple days in the Black Hills, with two adults (and another C. nebraskana!) being my reward.

The individual shown in the above photo was an unexpected surprise. It was captured a day later in the Sandhills proper at a locality where I expected to see not this species, but C. limbata (which I did succeed in finding at a nearby locality – see “Cicindela limbata – epilogue“). When I first saw this individual, I thought it was the ever present C. formosa (pictured below), which it greatly resembles and which, along with C. scutellaris, occurs commonly in suitable sand habitats throughout the Sandhills. Cicindela formosa formosaSomething about the way it flew gave me pause, however, and after capturing and looking closely at it in my hand I realized what it was. Cicindela lengi is distinguished from C. formosa morphologically by its slightly narrower form and longer, narrower labrum, but the quickest field identifier is the obliquely straight humeral marking (“C”-shaped in C. formosa). There are subtle behavioral differences also – both species are alert and quick to fly, but C. lengi lands quickly after a short flight, whereas C. formosa flies further and tends to land with a comical bounce and tumble or two across the sand. Cicindela lengi and C. formosa are not closely related despite their similar appearance – the former is assigned to subgenus Cicindela (Tribonia), while the latter is assigned to the nominate subgenus. The individual pictured above represents the nominate C. lengi lengi – populations north of Nebraska and Colorado exhibit a distinct coppery underside to the thorax and are assigned to subspecies C. lengi versuta, while populations in the southwestern part of its range show broadly coalesced elytral maculations and are assigned to subspecies C. lengi jordai.

REFERENCES:

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.

Spomer, S. M., M. L. Brust, D. C. Backlund and S. Weins. 2008. Tiger beetles of South Dakota & Nebraska. University of Nebraska-Lincoln Special Publication, 60 pp.

You messin’ with me?

Cicindela formosa formosa

This is another one of the tiger beetles I brought back alive from the Sandhills of western Nebraska since I was unable to get any good photographs of this species in the field.  If this photo looks familiar, you may recall this headshot of another individual, representing the eastern subspecies (Cicindela formosa generosa), that I took back in September in southeast Missouri.  Compare the two photos to see the distinctly reddish dorsal coloration of nominotypical C. formosa versus the darkened coloration of C. formosa generosa.  Nominotypical C. formosa also has a much more violaceous ventral coloration.

If this guy looks a little angry, it’s because he is! I had prodded and poked him for some time by the time this photo was taken, trying to coax/force him away from the edge of terrarium in which I had him confined.  Every time I thought I had him sitting still in a good position, he would run suddenly and make a beeline to the edge – a most unphotogenic place.  He even reached up a few times, seemingly out of shear frustration, and bit at my finger while I tried to push him back away from the terrarium wall (talk about biting the hand that feeds you!).  Finally I got him sitting still in the middle of the terrarium – his half-cocked mandibles suggesting exhaustion or rage, or maybe both.

Like the Cicindela limbata individual from the same locality that I brought back alive for photographs, this little beast lived for 10 weeks in his terrarium before, ahem… donating his body to science.   Also like C. limbata, he amusingly reached up and grabbed caterpillars directly from the forceps almost every time one was offered.  I think my colleagues in the lab enjoyed feeding time as much as the tiger beetle!

Buppies in the bush(veld)

In writing an article for the most recent issue of SCARABS, I found myself reliving some long-dormant memories of my trip to South Africa. It was nine years ago right about this time of year when I made what was to become the collecting trip of a lifetime. What a completely different November/December experience compared to the gray skies and bare trees I see outside my window today. Writing that article was a lot of fun – going back through my slides (yep, slides – no digital for me then), reviewing material in my collection, and trying my best to recall some long forgotten details. Using a long-handled tropics net to collect Evides spp. from upper branch terminals of Lannea discolor at Geelhoutbos FarmOf course, scarabs were not my reason for going to Africa – buprestids were! Although I did manage to sneak a few buprestid photos into the SCARABS article, for the most part I was a good boy and kept my focus on the that newsletter’s intended subject. It wasn’t hard, given the gorgeous diversity of “dungers” (dung beetles) and flower chafers that I encountered in that spectacular country. Here, however, I offer a sampling of the Buprestidae I encountered during that trip.

Much of trip was spent in the bushveld (pronounced “bushfelt”) tropical savanna – a mix of grassland and semi-deciduous forest – below the rugged and rocky Waterberg Mountains, their rugged exposures of 2.7 billion year old sandstone and quartzite providing a spectacular backdrop. I’ve already posted a photo of Evides pubiventris, the largest and most spectacular buprestid seen there. A handsome, iridescent green that must be seen to be believed, these elusive beetles spend their days high off the ground on the upper branch terminals of their host trees, Lannea discolor. Success in collecting these beetles comes only to those willing to give it considerable effort. In this photo, I use a long-handled tropics net and tap the rim of the net on the undersides of the branch terminals. The adults are alert and quick to fly but often enough drop from the foliage into the net before taking flight. Many hours were spent during the several days we were at this spot with my neck craned upwards, but my efforts were richly rewarded with several specimens of E. pubiventris and the closely related E. interstitialis.

Agelia petalii - South Africa, Limpopo Province, vic. Waterberg Mountains, Geelhoutbos Farm, 30.xi.1999, on Grewia monticolaAnother of the more spectacular buprestids seen on the trip was Agelia petelii, a not too distant relative of Evides (both are in the subfamily Chrysochroinae, containing the bulk of the “classic” jewel beetles). Several individuals of this species were seen here in the Waterberg and also at Borakalalo National Park in North West Province. Their bold markings would seem to make them conspicuous targets for predation by birds but actually serve as protection by mimicking the warning coloration of Mylabris oculata, a common blister beetle in southern Africa that occasionally reaches pest status on leguminous crops and that is – like all blister beetles – largely protected from predation by the cantharidins in its hemolypmph. Many of these blister beetles were seen during the trip, and I had to pay close attention to each of them in order to secure my half dozen or so specimens of the much less common A. petelii.

Meliboeus punctatus - South Africa, Limpopo Province, 8.5 km S of Piesmoor River, 4.xii.1999, on unidentified Grewia-like shrubThis gorgeous little beetle, seen south of the Waterberg near the Piesmoor River, belongs to the enormously diverse but poorly known tribe Coraebini. This tribe – a cousin to the even more diverse genus Agrilus (see this post) – is represented by only a few species in North America but is richly represented in sub-Saharan Africa and Madagascar. Chuck Bellamy – my friend, colleague, and host during this trip – probably knows more about coraebines than anybody alive and has identified this as Meliboeus punctatus. The plant on which the beetles were found remains a mystery – it looks similar to plants in the rhamnaceous genus Grewia on which we saw so many other buprestid species but is clearly not a member of that genus. It is one of the few buprestids I collected on the trip for which I did not obtain host information (I hate that!).

Acmaeodera (Paracmaeodera) viridaenea swierstrae - South Africa, North West Province, Borakalalo National Park, along Moratele River, 24.xi.1999, on Grewia flava blossomThe genus Acmaeodera is another of the hugely diverse groups in the family, having radiated in all the biogeographic realms except Australian. This group is especially well represented in North America, with some 150 species occurring in our desert southwest and many more occurring down into Mexico. The vast majority of these are variously patterned with yellow and/or red markings on a black background. In southern Africa the genus is also diverse but shows greater diversity of form and has, accordingly, been divided into a number of well-defined subgenera. Like our North American species, adults of many African species are frequently found on flowers, where they feed on pollen and petals. I encountered at least a dozen Acmaeodera spp. on the trip, with one of the more striking species being A. (Paracmaeodera) viridaenea. Acmaeodera (Rugacmaeodera) ruficaudis - South Africa, South Africa, Limpopo Province, vic. Waterberg Mountains, Geelhoutbos Farm, 1.xii.1999, on Grewia flava blossomLike other species in this subgenus, adults are brilliantly colored and sexually dichroic, with the individual pictured here (above, left) being a female and the males being greenish brown with coppery sides. Other species are quite somber colored, such as A. ruficaudis in the subgenus A. (Rugacmaeodera) (right). Both of these individuals were found on flowers of Grewia flava.

Discoderoides immunitus - South Africa, South Africa, Limpopo Province, vic. Waterberg Mountains, Geelhoutbos Farm, 1.xii.1999, on Grewia flavaNot all “jewel beetles” do their name justice. This small species – Discoderoides immunitus (another member of the tribe Coraebini) – appears to resemble a piece of caterpillar frass. Several individuals were seen, all sitting on the leaves of Grewia flava like this individual rather than visiting the flowers like Acmaeodera. This beetle reinforced an important lesson I have learned repeatedly about field identification – upon my return to St. Louis, when I had an opportunity to examine these individuals more closely under the microscope, I found one specimen mixed in the batch that was, in fact, not this species, but a species in the closely related genus Discoderes. Moreover, that individual appears to represent an as yet undescribed species. Pity that I found only the single individual, since describing species from such uniques is not very desireable. Regardless, I’m glad I didn’t assume this individual was yet another D. immunitis in the field and pass it by – keeping the species in the still too-swollen ranks of the unknown and unseen.

One of the most exquisite species that I collected was Anadora cupriventris – a very large (by coraebine standards), heavily sculptured species densely covered with curled swaths of gold and brown pubescence. I regret not having the opportunity to photograph the single individual that I found. Another impressive species that I was not able to photograph was Agrilus (Personatus) sexguttatus, surely close to, if not the largest species in the genus and boldly patterned with black and rust red spots on olive green. One last species for which I have no images but is worthy of mention is an undetermined species of the genus Pseudagrilus. Looking like a chunky, brilliant green Agrilus with saltorial (jumping) metafemora, adults would “pop” off the Solanum plants on which they were found as soon as I looked at them. I eventually decided that “Flipagrilus” would have been a more appropriate name for the genus. All told, I collected some 66 species of Buprestidae, including several genera not previously represented in my collection (e.g., Brachmaeodera, Brachelytrium – a few becoming paratypes of new species then being described by Chuck Bellamy and Svata Bílý, Chalcogenia, Galbella, and many of the other above mentioned species). I should mention the assistance of Chuck and Svata for helping me with some of the identifications, as well as Gianfranco Curletti who identified all of the material in the difficult genus Agrilus. I sincerely hope that I have another chance to visit this incredible land of beauty and contrast!