Arthropoda

Arthropods – insects, arachnids, crustaceans, myriapods, & relatives

I am an Entomologist

/ Ted C. MacRae / 21 Comments

In my last post (Best of BitB 2011), I showed my favorite 13 insect (mostly) macrophotographs from 2011. Such “Best of …” posts have become an annual tradition here at BitB, and I like them because they give me a chance to review my photographs for the year and assess my progress as an insect macrophotographer. Others seem to like them also, as previous editions remain among this blog’s most popular posts despite the passage of time. Hopefully this latest edition will achieve similar popularity, and if it does I will be truly grateful.

Despite this, however, I find that I still have trouble considering myself a true “insect macrophotographer” rather than an “entomologist with a camera.” It’s not that I don’t want or hope to achieve such a moniker, and I’ve been thinking lately about why this should the case. I’ve realized that it really has less to do with self-opinion and more to do with the importance I still place on and satisfaction I get out of my other entomological pursuits. Not only have I been fortunate to find stable employment conducting entomology research, but I’ve also managed to find satisfying outlets for my avocational entomological interests. I am an Entomologist (with a capital ‘E’), and although I’ve enjoyed immensely my recent growth as an insect macrophotographer, I did have other other, purely entomological accomplishments in 2011 that I think also deserve mention:

  • Managing Editor of The Pan-Pacific Entomologist. It has been my life-long goal to become editor of a major entomology journal, and this past April I was presented with just such an opportunity with The Pan-Pacific Entomologist. My seven prior years as the journal’s Coleoptera Subject Editor prepared me well for the role (and further confirmed for me that the chief role was something I wanted to do), and in the seven months since I took over, the Editorial Board and I have processed 50 manuscripts, are about to submit files for our 4th issue, and have shaved more than two months off of the deficit that separates us from our eventual goal of on-schedule publishing.
  • Five papers published. With co-authors Chris Brown and Kent Fothergill, 2011 saw the publication of our series of papers assessing the conservation status of the tiger beetles Habroscelimorpha circumpicta johnsonii, Dromochorus pruinina, Tetracha carolina, and Cylindera cursitans in Missouri and Cylindera celeripes in the eastern Great Plains. Survey work for these species dominated my field activities during the past decade and formed the basis for these papers, and it was immensely satisfying to finally see the results of all that work finally appear in print. The real impact of this work, however, will be seen in the coming years as I work with conservation stakeholders who will utilize the information that we have gathered.
  • First seminar presented fully in Spanish. I don’t talk much about my professional activities—part of being an industry entomologist is the necessity to maintain company confidentiality. I have mentioned, however, my role in soybean entomology research and my recent travels to Argentina as part of this work. In November I finally realized one of my professional goals of giving a seminar fully in Spanish. It was a long time coming—I took Spanish lessons for a short time in the late 1990s but have otherwise had only one or two trips per year to Argentina and Mexico with which to improve my skills. It was during my trip to Argentina this past March that something finally ‘clicked’ and I found myself for the first time able to engage fully in conversation. My colleagues in Argentina must have noticed this as well, as it was they who requested that I not only give a seminar during my November visit, but that I do so in Spanish. The presentation went well, and I now find myself more motivated than ever to pursue what before seemed only a pipe dream—full fluency.
  • Senior Research Entomologist. After three decades of working as an entomologist—the last two in industry, I now can add “Senior” to my title. What this means in practice I’m not quite sure—I’m still doing largely what I have been doing for the past few years, and in this environment compensation is linked more to accomplishments than title. Maybe it’s just recognition of dogged persistence. Still, it sounds cool and looks good in the email signature line!
  • 32 species/subspecies of tiger beetles! This is the fun stuff! Nothing is more enjoyable for me than locating, observing, and photographing tiger beetles in their native habitats. It’s even better when they are uncommonly observed or rare endemic species. In 2011 I looked for tiger beetles in seven states (Arkansas, Colorado, Florida, Idaho, Missouri, Oklahoma and Utah), and of the 32 total species and subspecies that I found (listed below) the highlights must include three of North America’s rarest tiger beetle species: Cicindela albissima (Coral Pink Sand Dune Tiger Beetle), Cicindela arenicola (St. Anthony Dune Tiger Beetle), and the recently rediscovered Cicindelidia floridana (Miami Tiger Beetle).  Another eight endemic or highly restricted species and subspecies were also found, and I was able to obtain in situ photographs of all eleven in their native habitat (as well as most of the non-endemics that I had not already photographed). In the list that follows, bold text indicates endemics, and links to any photographs I posted are provided when available:
    • Genus Cicindela
      • Cicindela albissima Rumpp, 1962 [photos]
      • Cicindela arenicola Rumpp, 1967 [photos]
      • Cicindela formosa formosa Say, 1817
      • Cicindela formosa generosa Dejean, 1831 [photos]
      • Cicindela formosa gibsoni Brown, 1940 [photos]
      • Cicindela lengi lengi W. Horn, 1908
      • Cicindela purpurea audubonii LeConte, 1845
      • Cicindela scutellaris scutellaris Say, 1823
      • Cicindela scutellaris yampae Rumpp, 1986 [photos]
      • Cicindela sexguttata Fabricius, 1775
      • Cicindela splendida Hentz, 1830
      • Cicindela theatina Rotger, 1944 [photos pending]
      • Cicindela tranquebarica borealis E. D. Harris, 1911
      • Cicindela tranquebarica kirbyi LeConte, 1866
      • Cicindela tranquebarica tranquebarica Herbst, 1806 [photos]
    • Genus Cicindelidia
      • Cicindelidia floridana (Cartwright, 1939) [photos]
      • Cicindelidia haemorrhagica haemorrhagica (LeConte, 1851)
      • Cicindelidia obsoleta vulturina (LeConte, 1853) [photos pending]
      • Cicindelidia punctulata punctulata (Olivier, 1790)
      • Cicindelidia rufiventris rufiventris (Dejean, 1825)
      • Cicindelidia scabrosa (Schaupp, 1884) [photos]
    • Genus Cylindera
      • Cylindera (Cylindera) curistans (LeConte, 1860) [photos]
      • Cylindera (Cylindera) unipunctata (Fabricius, 1775) [photos]
    • Genus Ellipsoptera
      • Ellipsoptera hamata lacerata (Chaudoir, 1854) [photos, photos, photos, photos]
      • Ellipsoptera hirtilabris (LeConte, 1875)
      • Ellipsoptera marginata (Fabricius, 1775)
    • Genus Habroscelimorpha
      • Habroscelimorpha dorsalis saulcyi (Guérin-Méneville, 1840)
      • Habroscelimorpha severa severa (LaFerté-Sénectère, 1841)
      • Habroscelimorpha striga (LeConte, 1875) [photos]
    • Genus Tetracha
      • Tetracha (Tetracha) carolina carolina (Linnaeus, 1767) [photos]
      • Tetracha (Tetracha) floridana Leng & Mutchler, 1916 [photos, photos]
      • Tetracha (Tetracha) virginica (Linnaeus, 1767)

Copyright © Ted C. MacRae 2012

Best of BitB 2011

/ Ted C. MacRae / 20 Comments

Welcome to the 4th Annual BitB Top 10, where I get to pick my 10 (more or less) favorite photographs of the year. As an insect macrophotographer I still feel like a relative newcomer, although with three seasons under my belt fewer and fewer people seem to be buying it anymore. Granted I’ve learned a lot during that time, but the learning curve is still looking rather steep. I don’t mind—that’s the fun part! With that said, I present a baker’s dozen of my favorite photographs featured here during 2011. I hope they reflect the learnings I’ve had the past year and maybe show some progress over previous years (2009, 2008 and 2010).

One more thing—I’m including a special bonus for the first time in this year’s edition. Each of the photos shown below is linked to a 1680×1120 version that may be freely downloaded for use as wallpaper, printing in calendars, or any other use (as long as it’s personal and non-profit). It’s my way of saying thanks for your readership and support.

From  (posted 8 Jan). I’ve done limited photography with prepared rather than live specimens. However, the recreated aggressive-defensive posture of this greater arid-land katydid (Neobarrettia spinosa)—or “red-eyed devil”—was too striking to pass up. A clean background allows every spine and tooth to be seen with terrifying clarity.

From  (posted 6 Feb). I had never seen a cactus fly until I encountered this Nerius sp. I’m especially fond of the bizzarely-shaped head and un-fly-like spines on the front legs.

From  (posted 17 Feb). This photo of a fungus weevil, Phaenithon semigriseus, is one of the first where I nailed the focus right on the eye at such a magnitude of closeup (~3X) and also got the composition I was looking for. I didn’t notice at the time, but the beetle seems to be “smiling.”

From  (posted 28 Mar). One of the field techniques I’ve been practicing this year is actually holding the plant with the subject in one hand, resting the camera on my wrist and controlling it with the other hand, and manipulating the position of the plant to achieve a desired composition. It’s a difficult technique to master, but the results are worth it. The jumping spider, Euophrys sutrix, represents one of my earliest successful attempts with this technique.

From  (posted 30 Mar). This South American tree fruit weevil looks like it is sitting quite calmly on a branch. In reality, it never stopped crawling while I attempted to photograph it. Crawling subjects are not only difficult to focus on but also almost always have a “bum” leg. I achieved this photo by tracking the beetle through the lens and firing shots as soon as the center focus point flashed, playing a numbers game to ensure that I got at least one with all the legs nicely positioned. I’d have been even happier with this photo if I had not clipped the antennal tip.

From  (posted 4 May). Face shots of predatory insects are hard to resist, and in this one of the fiery searcher beetle, Calosoma scrutator, the angle of the subject to the lighting was perfect for showing off every ridge and tooth in its impressive mandibles.

From  (posted 10 May). I’ve taken plenty of lateral profile shots of tiger beetles, but I like this slightly panned out one especially because of the sense of scale and landscape created by the inclusion of the plantlets and the view over the small rise.

From  (posted 18 May). I found these Edessa meditabunda stink bug eggs on the underside of a soybean leaf in Argentina almost ready to hatch. The developing eye spots in each egg gives the photo a “cute” factor rarely seen in such super close-ups.

From  (posted 15 July). Some of my favorite insect photos are not only those that show the bug in all its glory, but also tell a story about its natural history. This nymphal lichen grasshopper, Trimerotropis saxatilis, is almost invisible when sitting on the lichens that cover the sandstone exposures in its preferred glade habitat. 

From  (posted 23 Aug). I know this is the second beetle face shot I’ve included in the final selections, but it was while photographing this rare Florida metallic tiger beetle, Tetracha floridana, in the middle of the night that I discovered the use of extension tubes to improve the quality of flash lighting (decreased lens to subject distance results in greater apparent light size). This is perhaps one of the best illuminated direct flash photographs that I’ve taken, and I also like the symmetry of the composition.

From  (posted 17 Sep). The three-cornered alfalfa hopper (Spissistilus festinus) is a common pest of alfalfa and soybean in the U.S. However, despite its abundance, I’ve never noticed the bizarre zig-zag pattern of the eyes until I took this photo. Even though both the insect and the background are green, there is sufficient value contrast to create a pleasing composition. Bumping up the ISO and a lower FEC setting prevented overblowing the light greens—easy to do with full flash macrophotography.

From  (posted 4 Oct). This longhorned beetle had settled in for the night on its Ericamera nauseosa host plant, allowing me to use higher ISO and lower shutter speed settings with a hand-held camera to achieve this very pleasing blue sky background, while retaining the sharpness of detail of the subject that comes from full-flash illumination. The blue sky background provides a more pleasing contrast with the colors of this particular beetle and flowers than the black background that is more typically seen with full-flash macrophotography.

From  (19 Dec). An uncommon underside view of these purple tree fungus (Trichaptum biforme) caps and use of flash illumination allows the colors to literally glow against the bright green lichens also growing on the tree. Keeping aperture at a moderate setting allows blurring of the caps further back, adding three-dimensionality to the photo and preventing it from looking ‘flat.’

Well, there you have it, and I hope you’ve enjoyed my selections. Please do tell me if you have a favorite among theses (and if there were other photos posted during 2011 that you think deserved making the final selections).

Copyright © Ted C. MacRae 2011

Hover fly on mallow flower

/ Ted C. MacRae / 17 Comments

I’ve mentioned before my reluctance to take random “bug on a flower” photos, but the colors of this hover fly (family Syrphidae) and the mallow flower (Malvaceae, possibly Abutilon pauciflorum) on which it was sitting were enough to capture my interest—a rare offering from this blog to dipterophiles. Even though I’m a beetle man, I’ve had reasonably good success identifying the varied insects across several orders and families that I’ve photographed at the Reserve. This one, however, has me a little stumped. I searched the syrphid gallery at Diptera.com but didn’t find a good match, the most similar being the Old World species Episyrphus balteatus. My best guess is something in the tribe Syrphini. Morgan? Keith? Phoridae?

Photographed last month at  in Buenos Aires.

Copyright © Ted C. MacRae 2011

Sometimes the best collecting…

/ Ted C. MacRae / 2 Comments

Anambodera sp. (prob. undescribed) | Nothing, Arizona

As a practicing (albeit non-professional) taxonomist, I spend a goodly amount of time examining specimens collected not only by me, but by others as well. I’ve mentioned before the benefits of doing this—both to the collector, who gets names for the specimens in their collection, and to my own research in being able to cast a broader net in my search for new distributions and host associations within my two primary focus groups—Buprestidae and Cerambycidae. Such information remains surprisingly incomplete for these two popularly collected groups of beetles, and every few years I assemble whatever records that I’ve accumulated to that point for publication in the form of a “notes” paper (e.g., Nelson and MacRae 1990, Nelson et al. 1996, MacRae and Nelson 2003, MacRae 2006, MacRae and Rice 2007). Occasionally I encounter species that I have not yet collected myself (although with ~70% of Nearctic species now represented in my collection, this is becoming more and more infrequent), and in most such cases the collector graciously allows me to keep an example or two (leading to the saying, “Sometimes the best collecting is in other people’s collections!” ☺). The ultimate find, however, is a specimen or series of specimens that represent an undescribed species. Yes, even amongst North America Buprestidae and Cerambycidae there are many species still awaiting discovery (imagine the situation with other families of beetles, many receiving far less attention than these two popular groups).

The beetle shown here, a member of the genus Anambodera, represents one such species. This individual is part of a small series collected in Nothing, Arizona this past summer by Paul Kaufman, an indefatigable amateur beetle collector who has routinely over the years provided fodder for my research in the way of new state records and, more recently, new larval host records through rearing. While the key characters that separate Anambodera from the closely related and exorbitantly speciose genus Acmaeodera (front margin of epistoma not reflexed or plate-like, front angles of pronotum rounded in side view, suture between 1st and 2nd abdominal sterna visible, etc.—see Barr 1972), the coarse elytral punctation and heavily sculptured and bronzed pronotal surface are classic gestalt for Anambodera and unlike any of the small, vittate species of Acmaeodera that they resemble. This specimen keys to A. gemina, but it clearly differs from that species in a number of characters. Anambodera is restricted to western North America, and species tend to be poorly represented in collections due to their more cryptic habits (unlike Acmaeodera, most tend not to visit flowers, but are instead found alighting on rock surfaces or bare soil). As a result, the genus is still incompletely known and in bad need of revision. Dennis Haines and George Walters are working on such a revision and have already found several undescribed species among material collected in Arizona—I’m sure they will be pleased to include these specimens in their study as well.

My sincere thanks to Paul Kaufman for faithfully sending to me for examination his “catch” at the end of each season and allowing me to publish information gleaned from the included specimens. Keep it up, Paul!

REFERENCES:

Barr, W. F. 1972. New genera and species of North American Buprestidae. Occasional Papers of the Biological Society of Nevada 39:1–13.

MacRae, T. C. 2006. Distributional and biological notes on North American Buprestidae (Coleoptera), with comments on variation in Anthaxia (Haplanthaxia) viridicornis (Say) and A. (H.) viridfrons Gory. The Pan-Pacific Entomologist 82(2):166–199.

MacRae, T. C., and G. H. Nelson. 2003. Distributional and biological notes on Buprestidae (Coleoptera) in North and Central America and the West Indies, with validation of one species. The Coleopterists Bulletin 57(1):57–70.

MacRae, T. C. and M. E. Rice. 2007. Distributional and biological observations on North American Cerambycidae (Coleoptera). The Coleopterists Bulletin 61(2):227–263.

Nelson, G. H., and T. C. MacRae. 1990. Additional notes on the biology and distribution of Buprestidae (Coleoptera) in North America, III. The Coleopterists Bulletin44(3):349–354.

Nelson, G. H., R. L. Westcott and T. C. MacRae. 1996. Miscellaneous notes on Buprestidae and Schizopodidae occurring in the United States and Canada, including descriptions of previously unknown sexes of six Agrilus Curtis (Coleoptera). The Coleopterists Bulletin 50(2):183–191.

Copyright © Ted C. MacRae 2011
 

Swift Tiger Beetle: Species on the Brink

/ Ted C. MacRae / 1 Comment

ResearchBlogging.orgIn July 2008, Chris Brown and I made a spur-of-the-moment trip to Hitchcock Preserve near Council Bluffs, Iowa, where only a week earlier Cylindera celeripes (Swift Tiger Beetle), one of North America’s most enigmatic tiger beetles, had just been discovered. Reportedly once common in the blufftop prairies of western Iowa and further west in eastern Nebraska and Kansas, this tiny (6–8 mm in length), flightless beetle has suffered severe population declines over the past 100 years. Only small numbers of individuals have been encountered outside of the type locality (Fort Riley, Kansas) in recent years, and in Nebraska the species is now considered extirpated (Spomer et al. 2008). Our reasons for going to Iowa had to do with our as yet unsuccessful effort to find the species in northwestern Missouri as part of our broader studies of the state’s tiger beetle fauna. Although it had never been recorded from Missouri, we felt there was some chance it might be found in the tiny loess hilltop prairie remnants still remaining in the state at the southern terminus of the Loess Hills landform. We reasoned our failure to find the species might be related to its very small size and rapid running capabilities (giving them more the appearance of small ants or spiders than tiger beetles), limited temporal occurrence, and tendency to hide amongst the bases of grass clumps (Pearson et al. 2006). If we could find the species at a locality where they were known to occur, perhaps an improved search image and better understanding of their precise microhabitat preferences would help us locate the species in Missouri.

Fig. 1. Cylindera celeripes (LeConte) adults at: a) Hitchcock Nature Center, Pottawattamie Co., Iowa (13.vii.2008); b) Alabaster Caverns State Park, Woodward Co., Oklahoma (10.vi.2009); c) same locality as “b”, note parasite (possibly Hymenoptera: Dryinidae) protruding from abdomen and ant head attached to right antenna; d) Brickyard Hill Natural Area, Atchison Co., Missouri (27.vi.2009). Photos by C.R.Brown (a) and T.C.MacRae (b-d).

We didn’t realize it at the time, but that trip marked the beginning of a two-year study that would not only see us succeed in finding C. celeripes in Iowa, but also discover new populations in Missouri and northwestern Oklahoma (Figs. 1a–d). With so much new information about the species and the long-standing concerns by many contemporary cicindelid workers about its status, it seemed appropriate to conduct a comprehensive review of the historical occurrence of this species to establish context for its contemporary occurrence and clarify implications for its long term protection and conservation. This was accomplished through compilation of label data from nearly 1,000 specimens residing in the collections of contemporary tiger beetle workers, all of the major public insect museums in the states of Iowa, Kansas, Missouri, Nebraska, Oklahoma, and Texas, and the collections at the U.S. National Museum and Florida State Collection of Arthropods. Collectively, this material is presumed to represent the bulk of material that exists for the species, representing nearly all localities recorded for the species and time periods in which it has been collected.

Label data confirmed the historical abundance of this species, especially in the vicinity of Manhattan and Fort Riley, Kansas; Lincoln and Omaha, Nebraska; and Council Bluffs, Iowa. Hundreds of specimens were routinely collected in the native grassland habitats around these areas during the late 1800s and early 1900s, their abundance documented by entomologists in both journal articles and private letters. One of the most interesting examples of the latter was by Nebraska collector F. H. Shoemaker, who wrote the following in a 1905 letter to R. H. Wolcott:

There is another trip, down the river to the big spring by the railroad track near Albright, then across the river (the heronry route) where we collect hirticollis, repanda, vulgaris [= tranquebarica], cuprascens, and – vat you call ‘im? – celeripes! I took 147 of the latter in an hour and a half Sunday, and the supply was undiminished.

Fig. 8. Historical and currently known geographical occurrence of Cylindera celeripes by county. Red = last record prior to 1920; orange = last record 1941–1960 (“?” = questionable record); green = last record 1991–1996; blue = last record 2005–2011.

Although the recent collections of C. celeripes from near Council Bluffs and through the years near Fort Riley show that the species has managed to persist in these areas, there is little question that it is far less abundant and widespread now than it was in the early 20th century (Fig. 8).  Not only are the areas in which present day populations are known to occur limited, but the numbers of individuals seen in them are very low. In Missouri, the species was listed immediately after its discovery in the state as a species of conservation concern with a status of S1 (= “critically imperiled”) due to the highly restricted occurrence of suitable habitat (loess hill prairie) in the state and small populations observed within them. The situation is even worse in Nebraska, where the species has not been seen for nearly 100 years despite dedicated searches by expert contemporary tiger beetle workers such as Matt Brust and Steve Spomer. Considering the near-complete elimination of suitable native grassland habitats by conversion to agriculture and degradation of the few existing remnants due to encroachment by woody vegetation and invasive exotics, the likelihood of finding extant populations of C. celeripes in Nebraska seems remote. Only in the Red Hills of northwestern Oklahoma does the species appear to be secure due to the extensiveness of suitable areas of habitat and robust numbers of individuals observed within them at the present time. An enigmatic record exists from Arkansas, based on a single individual collected near Calico Rock in 1996. This individual represents a significant extension of the known geographical range of the species, but repeated attempts to find the species at that locality during the past year were not successful.

The persistence of populations, albeit small, in multiple areas, along with the occurrence of robust populations in northwestern Oklahoma, makes it unlikely that C. celeripesqualifies for listing as a threatened or endangered species at the federal level. Nevertheless, the limited availability of suitable habitat in many areas and low population numbers found within them clearly suggest that conservation measures are warranted at the state level, especially in Iowa, Kansas and Missouri, to prevent its extirpation from these states. In these states, land management practices should be implemented at sites known to support populations of the beetle in an effort to maintain and expand the native grassland habitats upon which they rely. These include various disturbance factors such as mechanical removal of woody vegetation, judicious use of prescribed burning, and selective grazing (taking care to do so in a manner that minimizes impacts to beetle populations).

REFERENCES:

MacRae, T. C. and C. R. Brown. 2011. Historical and contemporary occurrence of Cylindera (s. str.) celeripes (LeConte) (Coleoptera: Carabidae: Cicindelinae) and implications for its conservation. The Coleopterists Bulletin 65(3):230–241 DOI: 10.1649/072.065.0304

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, Department of Entomology, Lincoln, 60 pp.

Copyright © Ted C. MacRae 2011

Cycloalexy in tortoise beetle larvae

/ Ted C. MacRae / 13 Comments

One of the first insects I encountered during my visit this past November to  in Buenos Aires, Argentina were these tiny beetle larvae grouped together on a single leaf of an unidentified shrub.  The presence of fringed lateral appendages and exuvial-fecal debris masses held by caudal appendages immediately identifies them as larvae in the leaf beetle subfamily Cassidinae, known commonly in North America as “tortoise beetles” due to the appearance of the adults.  With nearly 3,000 species distributed throughout the world, tortoise beetles are easily recognizable as a group; however, species identifications can be much more difficult, especially in the Neotropics where the group reaches its greatest diversity (Borowiec and Świętojańska 2002–2011). Identification of larvae can be even more challenging, as the larvae of many species remain unknown, and I was unable to find adults in association with the larvae to aid my identification.

Anacassis sp. (poss. exarata) early-instar larvae on Baccharis salicifolia | Buenos Aires, Argentina

Nevertheless, host plant can be an important clue to leaf beetle identity, as most species in the family limit their feeding to a single plant genus or group of related plant genera. The shrub on which the beetles were feeding looked familiar to me, and while perusing a list of plants that have been recorded from the Reserve (Burgueño 2005) I had an “Aha!” moment when I spotted the asteraceous genus Baccharis. I decided the plant must represent Baccharis salicifolia because of its narrowly lanceolate, willow-like leaves with fine apical serrations (Cuatrecasas 1968) (see first photo). The only tortoise beetles known to feed on Baccharis are species in the genus Anacassis (McFadyen 1987), several species of which are known from Argentina, and one (Anacassis exarata) looking very much like the larvae in these photos.

Note the circular, heads-directed-inward orientation of all larvae around the periphery

The manner in which these early-instar (perhaps even newly hatched) larvae were feeding as a group while working their way down the length of the leaf towards its base is not something I had observed before. Larvae of most tortoise beetles are solitary feeders (Borowiec and Świętojańska 2002–2011), and I was further intrigued by the deliberate circular formation that the larvae had assumed.  The larvae around the periphery were all facing inward, tightly packed against each other and with their exuvial-fecal debris masses directed outward. Additional larvae were seen inside the circular formation. As I manipulated the leaf for photographs, the larvae would occasionally raise their debris masses up and outward, presumably a defensive reaction to disturbance and a perceived threat. It was clear to me that the larvae had deliberately “circled their wagons” for defensive purposes.

Close body contact allows exuvial-fecal debris masses to form a protective barrier against predators

In fact, this type of defensive strategy has been reported in a number of South American cassidines, as summarized by Jolivet et al. (1990), who coined the term “cycloalexy” (from the Greek κύκλος = circle, and αλεξω = defend) to describe such strategies. Cycloalexy can either be “heads in, tails out” or vice versa and is usually associated with other repellent activities such as coordinated threat movements, regurgitation, or biting. The strategy is intended to provide protection from predators such as ants and true bugs and parasitioid wasps, although some parasitoids seem to have thwarted the strategy by depositing their eggs where they can be ingested (thus avoiding direct confrontation with the prey). Cycloalexy has been described primarily among chrysomelid beetles and tenthredinoid hymenopterans (sawflies); however, examples from a few other insect orders (e.g., Diptera, Neuroptera, Lepidoptera) are known as well (Jolivet 2008).  All known cycloalexic insects are subsocial in the larval stage and often also exhibit maternal protection of eggs or newly hatched larvae.

This and several other older larvae had become solitary, presumably protected in part by greater size

In addition to this single group of early instar larvae, I noted also a few larger individuals—all of whom were feeding on the plant in a more solitary fashion. Presumably as the larvae grow larger they are more able to defend themselves, or perhaps larger larvae simply demand more “elbow room” because of the larger amounts of leaf tissue they require for feeding. If cycloalexy is beneficial for small cassidine larvae but less so for larger larvae, perhaps this behavior is actually more common than is currently realized.

REFERENCES:

Borowiec, L., and J. Świętojańska. 2002–2011. Cassidinae of the world – an interactive manual (Coleoptera: Chrysomelidae). http://www.biol.uni.wroc.pl/cassidae/katalog%20internetowy/index.htm [accessed 3 Dec 2011].

Burgueño, G. 2005. Manejo de la vetación en reservas naturales urbanas de la region metopolitana de Buenos Aires. Aves Argentinas, Asociación Ornitológica del Plata, Proyecto Reservas Naturales Urbanas, 16 pp.

Cuatrecasas, J. 1968. Notas adicionales, taxonómicas y corológicas, sobre Baccharis. Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales 13(50):201–226.

Jolivet, P. 2008. Cycloalexy. In: J. L. Capinera [Ed.], Encyclopedia of Entomology, Springer Science+Business Media B.V.

Jolivet, P., Vasconcellos-Neto, J., and Weinstein, P. 1991. Cycloalexy: A new concept in the larval defense of insects. Insecta Mundi 4(1–4) (1990):133–141.

McFadyen, P. J. 1987. Host-specificity of five Anacassis species [Col.: Chrysomelidae] introduced into Australia for the biological control of Baccharis halimifolia [Compositae]. Entomophaga 32(4):377–379.

Copyright © Ted C. MacRae 2011

‘Beetles in the Bush’ T-Shirts now available!

/ Ted C. MacRae / 8 Comments

I’ve mentioned before my preference for simple cotton t-shirts over fancy pocketed nylon shirts while I’m out in the field (see Beetle Collecting 101: Dress for Success). Lightweight and comfortable under even the most extreme conditions, they do the job cheaply and effectively. While most any t-shirt will do, I am especially fond of the set I purchased from CafePress, each artfully emblazoned with a stylized image of Cicindela ancosisconensis by Kirk Betts at The Wild Edge. In addition to their lightweight comfort, these shirts leave curious onlookers with little doubt about what I am up to (and of course, I also clearly be stylin’!).

Of course, variety is the spice of life, and I’m happy to now announce a new design created specifically for ‘Beetles in the Bush’. My deepest appreciation to Kirk, who has once again worked his PhotoShop filters magic to create a stylized image of this blog’s icon, the jewel beetle Agelia petalii (see Buppies in the bush(veld) for the original photo of this species that I took in South Africa back in 1999). Men’s, women’s and children’s t-shirts and other apparel bearing this design are now available at the new Beetles in the Bush CafePress online store. Two versions of each item are offered—one with the image and ‘Beetles in the Bush’ logo, and another with the image only, as shown below:

Image w/ logo

Image only


A variety of t-shirt and sweatshirt styles are available, as are coffee mugs for those who (like me) prefer to start their collecting day with a jolt of java! I hope you’ll browse the product selection and find something that you like.

Show your support for ‘Beetles in the Bush’! I don’t expect to get rich off of this, but whatever proceeds from sales that I do get will go a long way towards helping fund future insect collecting and photography expeditions. If you have any feedback on the design/organization of the online store, the products offered, or future designs that you would like to see made available please let me know, either by comment or by contacting me directly.

Copyright © Ted C. MacRae 2011

Arriving now in a mailbox near you…

/ Ted C. MacRae / 5 Comments


The latest issue of Cicindela (A quarterly journal devoted to Cicindelidae) has just been issued. My copy arrived yesterday and features on the cover a photograph that I took of Tetracha carolina in Florida this past August (original photo and more can be seen in my post ).

I’m also happy to report that I was lead author and co-author on the two papers included this issue. I’ll provide a more detailed summary of those papers in another post—look for it in the near future, or better yet contact Managing Editor Ron Huber to begin receiving your own copies of this fine journal (subscription and contact information here).

Copyright © Ted C. MacRae 2011