The World’s Largest Tiger Beetle

Manticora scabra - male (L) and female (R) | Republic of South Africa

Some of the first residents of my new insect cabinets (see ) are also among the newest specimens in my collection. Not long ago I received a box from world tiger beetle expert David Brzoska, who had carefully chosen male/female pairs of a number of tiger beetle species from his impressive world collection and sent them to me as a surprise gift. Now, us North America-bound collectors are limited to just a few genera, e.g. Cicindela (although increasingly recognized as a cluster of several closely related genera), Tetracha, and if we’re really lucky Amblycheila and Omus (the last being one I still have not seen in the field). In the rest of the world (especially the tropics and subtropics), however, generic diversity is much higher, and coming as they did from South America, Africa, Australia, and southeast Asia most of the specimens in the sending represented new genera for my collection. While I was grateful for them all, the specimens that had me leaping for joy was this fine pair of Manticora scabra, one of the so-called “African Giant Tiger Beetles.”

Males of all Manticora spp. have asymmetrically enlarged mandibles

In the case of these beetles, the term “giant” is no exaggeration. The male specimen (above and left) measures a full 54 mm (that’s more than 2 inches, folks!) from the tip of its grossly enlarged mandible to the tip of its abdomen, and even the female at 47 mm length is substantially larger than my 38-mm long male specimen of North America’s largest tiger beetle, Amblycheila cylindriformis. While enlarged male mandibles are a common feature among many beetle groups, Manticora males feature an unusual asymmetry in the mandibles, with the right mandible always much larger than the left (itself enlarged compared to the female mandibles, and even the latter cannot be considered small).  Apparently the asymmetry represents a trade-off in natural selection—males use their mandibles not only to hunt prey but also hold onto the female pronotum during mating and subsequent mate guarding. There is positive selection pressure for larger mandible size, as males with smaller mandibles are more likely to be dislodged from the female by competing males. However, because of the large size of the species, larger male mandibles are less effective for securing normal prey items that tend to be smaller in size. If both mandibles were enlarged to the point needed to securely grip the female pronotum, the male would be unable to feed adequately, but having only one mandible fully enlarged provides sufficient grip while maintaining an ability by the somewhat smaller left mandible to grip regular prey items. A consequence of the mandibular asymmetry is that males ride “to the left” when coupled with females.

The right mandible is larger than the left mandible.

David identified these individuals as the species M. scabra, occurring throughout much of southern Africa (Botswana, Malawi, Mozambique, Republic of South Africa, Tanzania, Zimbabwe—according to Carabidae of the World). I presume the species epithet refers to the roughened surface of the elytra. There are at least two recent treatments of the genus (Werner 2000, Mares 2003); however, I have access to neither because of the exorbitant cost of these books—$247 and $433, respectively (I find it rather ironic that the recent explosion of book-sized treatments of “large” beetles has resulted in publications priced so high that they are inaccessible to most professional entomologists).

Female mandibles are nonetheless impressive despite their smaller size.

I made a trip to South Africa in 1999 and had hoped to see these beetles for myself, but unfortunately this did not happen. Perhaps part of the problem was my impression of these beetles as nocturnal hunters—the prevailing ‘wisdom’ at the time. My field partners and I made several nighttime forays in the semi-arid bushveldt where we were camping, using flashlights to scan the ground for any large black beetles we could find moving about. We found numerous tyrant ground beetles (family Carabidae, genus Anthia) and a diversity of tok-tokkies (family Tenebrionidae), but no Manticora tiger beetles. Shortly after that trip, Oberprieler & Arndt (2000) published an informative summary of the biology of several Manticora populations in South Africa, their most notable finding being that adults are opportunistic diurnal predators that hunt by smell rather than nocturnal visual hunters. Perhaps someday I’ll have another opportunity to visit South Africa and see Manticora adults in the field, but until that time I’m happy to have these two specimens residing in my cabinet.

My sincerest thanks to David Brzoska for these sending me these fine specimens and for the many additional kindnesses he has extended to me during the past few years.

REFERENCES:

Mares, J. 2003. A Monograph of the Genus Manticora. Taita Publishers, 205 pp.

Oberprieler, R. G. & E. Arndt. 2000. On the biology of Manticora Fabricius (Coleoptera: Carabidae: Cicindelinae), with a description of the larva and taxonomic notes. Tijdschrift voor Entomologie 143:71–89.

Werner, K. 2000. The Tiger Beetles of Africa (Coleoptera, Cicindelidae) Volume I. Taita Publishers, 191 pp.

Copyright © Ted C. MacRae 2012

MacRae Entomology Museum Expansion

Badly needed drawer space is provided by these gorgeous, antique, hand-made, wooden insect cabinets.

Every five years or so I find myself facing the same dilemma—too many bugs and not enough space to keep them. Each time this occurs, I go through the same thought process trying to decide the best way to solve the problem. Do I create new space by buying new cabinets, or clear existing space by donating “excess” material? If money was no object it would be the former. However, money is an object—a new, premium 25-drawer cabinet costs more than $1,000, not to mention another $400 for the drawers to fill it (if I build them myself—3 times that amount if I buy them already made). In my younger, more care-free days I got away with plunking down this kind of money several times, eventually assembling my current battery of three half-size and three full-size cabinets holding a total of 111 Cornell drawers fully stocked with unit trays. These days, however, there are kids to feed and college costs looming on the horizon. I just can’t swing that kind of dough.

Each cabinet came complete with 10 hand-made, wooden, glass-topped drawers.

The alternative, however—donating away part of my collection, is equally unattractive. I’ve been collecting insects for most of my life, so it’s more than just a hobby—it’s a part of me. Nevertheless, I am able to draw a distinction between a working collection and a hobby collection, and for the most part mine is the former. I have a few “hobby” taxa like treehoppers and leaf beetles and such, and I’ve already made a number of donations from these groups over the years. However, the bulk of my collection—and hence drawer space—is taken up by just three taxa; jewel beetles, longhorned beetles, and tiger beetles. Not only are my research activities in these three groups ongoing, but a considerable amount of the material in these groups consists of voucher specimens for my publications. I just can’t think about divesting myself of material in these groups, at least not at this point in my life. Besides, pulling material for donation is, in itself, a long and very time-consuming process that I would not look forward to.

I’ve actually been debating my options for the past couple of years now, watching nervously as my inventory of specimens housed in temporary cardboard boxes started to balloon from the successes of the past several years of collecting. Temporary boxes are bad—not only is it impossible to integrate the specimens into the organization of the main collection, but they remain vulnerable to that dreaded pest of insect collectors around the world; DERMESTID BEETLES! (The one beetle I don’t like!) The likelihood of having specimens damaged by dermestids is directly proportional to the number of temporary boxes that must be checked periodically looking for any evidence of their presence. I’ve been hit by dermestids more than once, and with the number of temporary boxes that I currently have (more than 50) it has become almost impossible to monitor them frequently enough.

Unit trays designed for Cornell drawers fortuitously fit nicely inside the custom-sized drawers.

Of course, patience is a virtue, and my reward this time for not acting too rashly came in the form of an email sent to the members of our local entomology group by Mark Deering, Director of the Sophia M. Sachs Butterfly House just a few blocks from my office. Mark was an avid butterfly collector in the past but has divested much of his collection in recent years and, as a result, no longer needed the cabinets and drawers he was using to store his collection. The list of items he had for sale included a few Cornell cabinets with drawers, ostensibly perfect for my needs, but it was the last item in the list that caught my eye—several antique, hand-made, wooden, 10-drawer cabinets with drawers. Now, I love my Cornell cabinets—they provide state-of-the-art (albeit industrial-looking) protection for my collection. However, there is something appealing about hand-made, wooden insect cabinets. I can almost see John L. LeConte and George W. Horn themselves standing next to one and pulling a drawer to have a look at its contents. I quickly contacted Mark and made arrangements to look at the cabinets. Mark explained that they were part of a 40-cabinet set housing a collection of pierid butterflies that eventually found its way to the Smithsonian Institution… yes, the Smithsonian (such history!). He had gotten ahold of seven cabinets and was now selling them for a very reasonable price. The cabinets were gorgeous, and it didn’t take long for me to do the math; I could afford to buy three cabinets with drawers for a fraction of what a 25-drawer Cornell cabinet with drawers would cost. That’s 30 drawers total, each with almost as much space as a Cornell drawer.

Drawer 1 of my tiger beetle collection.

I picked up the cabinets a few days later and spent the next two days rearranging furniture in my ‘museum’ to create the perfect showcase spot, cleaning the glass on each drawer (both sides), and transferring my tiger beetle collection into the first cabinet (drawer 1 of which is shown at right). Despite their age several transfers of ownership, the finish is still in very good shape with only minor nicks and scratches that add a sense of history yet don’t detract from their attractiveness. Especially pleasing was the discovery that the Cornell unit trays I use for my collection fit almost perfectly in the drawers (just an annoying empty spot in the upper right corner—this can probably be fitted with a California Academy-sized unit tray, perhaps for holding insect repellent blocks since the drawers and cabinets are not as air-tight as my modern Cornell cabinets). I’ll probably move the rest of my “hobby” taxa into the remaining drawers to free up the Cornell cabinets completely for exclusive use in housing my Buprestidae and Cerambycidae. That will take some time, but it’s a good problem to have. My only fear is that after I move things around and incorporate all of my backlogged material, I will have once again used up all of the newly available drawer space and find myself facing that same dilemma that I face every five years or so!

Perhaps a little teaser is in order—one of the species in the drawer shown at right will be the subject of an upcoming post—can you guess which one? Also, 2 BitB Challenge points to anyone who can correctly identify the country shown in the map behind the drawer.

Copyright © Ted C. MacRae 2012

My favorite Super Bowl Commercial

In addition to choosing sides in the game itself, my wife and friends and I always enjoy picking our favorite commercials. My favorite this year came after the game was over but is an obvious choice: “Bugs on Grill” for the Chevrolet Sonic. I even like it better than last year’s favorite, Volkswagon Beetle!

Did everyone remember to go pee-pee?

Vodpod videos no longer available.

Copyright © Ted C. MacRae 2012

Pollen Bath

Spintherophyta (?) sp. in flower of Abutilon pauciflorum | Buenos Aires, Argentina

One of the smallest insects I saw during my latest visit to  (Buenos Aires, Argentina) was this tiny leaf beetle (family Chrysomelidae) feeding in the flower of a malvaceous plant that I take to be Abutilon pauciflorum. At only ~4 mm in length, it could have easily gone unnoticed had I not noticed there were several feeding in flowers in a small, localized area. The best I could come up with for an ID was subfamily Chrysomelinae due to their globular shape, although the small size didn’t seem right. Turns out I’d forgotten to consider the Eumolpinae, which also contains globular species that are usually much smaller than those in the Chrysomelinae, and according to leaf beetle specialists Shawn Clark and Ed Riley this is likely a member Spintherophyta or a closely related genus.

Covered with tasty, sticky pollen!

Although there are only four species of Spintherophyta in North America (Schultz 1976), and of those only S. globosa is widespread and commonly encountered, the diversity of the genus explodes in the Neotropics (Blackwelder 1946 lists 71 species). Accordingly, neither Shawn nor Ed were brave enough to venture a guess as to which species this might represent. I should probably defer to their good sense, but part of me wonders if that coppery pronotum might suggest S. cupricollis—one of only two species in the genus listed by Blackwelder (1946) for Argentina.

REFERENCE:

Blackwelder, R.E. 1946. Checklist of the coleopterous insects of Mexico, Central America, the West Indies, and South America. Bulletin of the U. S. National Museum 185:551-1492.

Schultz, W. T. 1976. Review of the genus Spintherophyta (Coleoptera: Chrysomelidae) in North America north of Mexico. Annals of the Entomological Society of America 69(5):877–881.

Copyright © Ted C. MacRae 2012

A Living Jewel – Madecassia rothschildi

In North America, beetles in the family Buprestidae are commonly referred to as “metallic woodboring beetles.” This may be a perfectly adequate name—accurate and descriptive, but it’s also a bit dry and not terribly imaginative. Personally, I much prefer the moniker given to these beetles by the rest of the world—”jewel beetles!” No other name better captures the essence of these dazzling insects—brilliant, sparkling, even gaudy in coloration and with the most exquisite of surface sculptures, and no other group of buprestids better typifies jewel beetles at their most extreme than the great tribe Chrysochroini—the ‘‘classic’’ jewel beetles! Members of this tribe are found throughout the world (Chalcophora, Texania, Lampetis and Dicerca are the most familiar North American genera) but reach their zenith in the ancient rainforests of Africa and southeast Asia—big, beautiful beetles with screaming iridescence of green, red, yellow and blue. Living jewels!

I have a fair number of chalcophorines in my collection, and among the more recent acquisitions is this fine specimen of the species Madecassia rothschildi. One of a pair of specimens given to me by friend and world buprestid-expert Chuck Bellamy, this larger of the two measures a whopping 45 mm in length (that’s almost 2 inches, folks!), surely near the top end of the range for this genus and paling only against such giants as Euchroma and Megaloxantha. The reddish-brown eyes on a brilliant green head, turquoise legs and white-flecked, wine-colored elytra are enough to make it stand out, but it is the distinctive yellow-lime “false eyes” that made me do a double-take when I first laid eyes on them after opening the box. A closer look at the eye spots reveals the yellow-lime area to be densely pulverescent.

Madecassia rothschildi and the two other species placed in the genus all hail from Madagascar (Bellamy 2008). This particular species must be rather common despite the well-chronicled disappearance of Madagascar’s native forests, as a quick Google search of the species name (or its older synonym, Lampropepla rothschildi) brings up a multitude of web sites for commercial insect dealers with this species in stock. The combination of its size, coloration, and availability must make it a popular item among philatelic collectors, and although I’m not a big fan of buying insects, I can understand the desire to purchase something as spectacular as this.

I’ll be the first to admit that these photos aren’t nearly as striking as Gianfranco Merati‘s photos of Polybothris sumptuosa, but they do well illustrate the iridescence that is common to these beetles. Iridescent coloration is due not to pigments in the exoskeleton, but rather the physical properties of different layers in the insect cuticle that reflect light of specific wavelengths in different directions (hence, resulting in apparent color shifts depending on the angle at which the subject is viewed).

Despite its commonness, it seems that virtually nothing known about the life history of this species or the host plants that it utilizes. Records in Madagascar are all from the south (Bellamy 2006), but all other references to this species consist exclusively of catalogue listings. A large, conspicuous, abundant species such as this almost begs for ecological studies—the “eye spots” can be presumed to function in predator avoidance, but how? What is the purpose of the dense brush of hairs inside the labrum (upper lip) and next to the mandibles, and why is the labrum itself so acutely emarginated? Adults are largely reproducers, not feeders—do these structures serve some other function not related to feeding? What about the dense covering of “pits” over most of the body surfaces—presumably they contain chemoreceptors for smell, but what? Host plant volatiles? Mates? Humidity? So many questions, so few answers. Imagine the even greater paucity of knowledge that exists for its smaller, less conspicuous relatives that also make their homes in the forests of Madagascar (most of them probably not adapting as well to the man-induced changes of the past century).


Congratulations to Tim Eisele, whose 13 pts not only nets him the win in Super Crop Challenge #11 but also moves him up to 2nd place in the overall standings for BitB Challenge Session #5 with 29 pts. Mr. Phidippus‘s 12 pts  just missed the win but keep him in well in command atop the overall standings at 43 pts. Strong showings by Dorian Patkus (11 pts) and Dennis Haines and Roy (10 pts each) also keep them in the overall hunt with 20, 25 and 28 pts, respectively. I suspect the top spot is now a lock, but it looks like we’ve got a real battle brewing for the remaining podium spots. There will be at least one more challenge in the current challenge session, and for the first time I am considering consolation prizes to the final 2nd and 3rd podium spots as well, so everybody will want to make sure they participate in the next challenge.

REFERENCES:

Bellamy, C. L. 2006. Insecta Coleoptera Buprestidae de Madagascar et des îles voisines. Catalogue annoté. Faune de Madagascar 92:1–267.

Bellamy, C. L.  2008. World catalogue and bibliography of the jewel beetles (Coleoptera: Buprestoidea),  Volume 1: Introduction: fossil taxa; Schizopodinae; Buprestidae: Julodinae—Chrysochroinae: Poecilonotini.  Pensoft Series Faunistica 76: 1-625.

Copyright © Ted C. MacRae 2012

Super Crop Challenge #11

It’s been almost 3 weeks since the last challenge, so how about a Super Crop Challenge? Okay, not a true super crop as this is a full-sized photo (is that a hint?), but since it’s a close-up view of a limited area of the subject I’ll call it such. What is shown in the photo below, and what is the beautiful beastie that owns it? I’ll give 2 pts each for structure name and owner order and family. Genus identification is probably a stretch (though not impossible), so I’ll give 2 pts as well for correct subfamily and/or tribe.  Standard challenge rules apply, including moderated comments (although tie-breaker points will be awarded to early birders with correct answers) and bonus pts for additional relevant information at my discretion. Good luck!

Copyright © Ted C. MacRae 2012

Another cover photo

Issue 43(4) of Cicindela (A quarterly journal devoted to Cicindelidae) is now hitting mailboxes (my copy arrived earlier this week), and for the second issue in a row the cover features one of my tiger beetle photos. Gracing the cover this time is the recently rediscovered Cicindelidia floridana, known only from a small area in the Miami metropolitan area of south Florida, and which I was fortunate to have the opportunity to see this past summer. Because the species is regarded as critically imperiled and a likely candidate for listing as an endangered species, the precise whereabouts of its habitat have not been disclosed. So far I am one of only a few people who have had the chance to photograph it in the field.

Now, some of you may think that because I serve as Layout Editor for the journal that I can horn in and put one of my own photographs on the cover whenever I want. This is not the case, and it was only because Managing Editor Ron Huber asked me if I had anything for the issue that I supplied the photo after having just done so for the previous issue. In actuality, we encourage others to submit their tiger beetle photographs for consideration, and since a majority of U.S. species have already been featured at some point over the years we especially encourage ex-U.S. photographers to submit their photos so that we can limit repetition. Obviously, C. floridana has never been featured on the cover before now, so it was a no-brainer choice for this issue.

The issue contains two delightful papers. The first is another by Mathew Brust on the stunningly gorgeous Cicindela pulchra that discusses not only additional northern range extensions in South Dakota and Wyoming, but also the rediscovery of the species in Nebraska far from the single previously known collection record in the state nearly 100 years ago! It is amazing to me that one of North America’s most conspicuously beautiful tiger beetle species has gone undetected for so long in such a large part of its range. The second paper by Dave Brzoska and Ron Huber is a long overdue biography of tiger beetle icon Norman Rumpp, who in his professional life was a rocket scientist (literally!) and as an avocation became one of North America’s leading authorities on tiger beetles (I am proud to claim ownership of Rumpp’s nearly complete set of The Coleopterists Bulletin). In addition to numerous publications and unpublished reports on tiger beetles in the western U.S., Rumpp described 12 species and subspecies of tiger beetles—including three of the western sand dune endemics that I have featured in recent weeks (Cicindela scutellaris yampae, C. arenicola, and C. albissima). What may not be appreciated is Rumpp’s sense of humor—well, just read the paper and see!

Copyright © Ted C. MacRae 2012

“My peripatetic quest for North America’s rarest tiger beetles”

This week I gave a presentation on my latest Annual Fall Tiger Beetle Trip to the Entomology Group of the Webster Groves Nature Study Society. With the exception of a brief 5 year period in the early 1990s while I lived in California, I’ve been active with this local nature study group for the past 30 years (and serving as newsletter editor since 2009). I’ve given my share of entomology presentations over the years to both professional and amateur audiences, but no matter how far I might travel or the size of the audience, I always enjoy my time with this small group of local entomologists. They are my roots—the people with whom I learned to collect and began my explorations of Missouri and beyond. We are joined not only by the bonds of common interest, but by shared experiences as well. There was a good turn out for the presentation, and my thanks to the Group for the interest they showed.

Nine days, ten states, 4,300 miles:
My peripatetic quest for North America’s rarest tiger beetles

The photographs used in the presentation have been seen in various posts here over the past few months, but I thought some may appreciate the chance to see them all together in presentation format. A PDF version of the original Powerpoint presentation can be downloaded by clicking on the link above (although with a file size of just over 18 MB a high-speed internet connection is recommended). My thanks to David Pearson, Professor of Biology at Arizona State University, for permission to include in the posted version scanned images and distribution maps from his supremely useful A Field Guide to the Tiger Beetles of the United States and Canada (the bible of North American cicindelophiles¹).

¹ If you have not yet bought this most excellent book, paperback versions can be bought new for as little as $41.74. Buy it and you’ll never fail another BitB tiger beetle ID Challenge!

If you download the presentation, please remember that all materials are copyright Ted C. MacRae unless attributed otherwise and may not be used without permission (personal use excepted) .

Copyright © Ted C. MacRae