Beetles In The Bush

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. Of 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.

Another 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.

This 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!).

The 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. Like 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.

Not 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!