Why I went to Georgia

Call me biased, but for my money few groups of beetles can match the maddening combination of beauty and difficult taxonomy of jewel beetles (family Buprestidae) (I can already hear the protestations of weevil and scarab workers). In the case of jewel beetles, much of the difficulty is due to a propensity for hyperdiverse genera. For example, in North and Central America more than half of the nearly 2,000 described species belong to just three genera—AcmaeoderaChrysobothris, and Agrilus. It’s enough to make many a casual coleopterist throw their hands in the air and ship their specimens off to “specialists” for identification. This is, strangely, for me part of their attraction. Any reasonably serious effort to study jewel beetles over a period of time is sure to uncover a wealth of new data, from previously unknown hosts associations and distributions to the alpha taxonomist’s raison d’être—new species!

Chrysobothris seminole

Chrysobothris seminole on its host, Chrysoma pauciflosculosa.

One of the more problematic jewel beetle groups is the “Chrysobothris femorata species-group”. For many years, these abundant and conspicuous members of forest and landscape ecosystems have confounded collectors, foresters, and extension entomologists alike. A recent revision of the group by Stan Wellso and Gary Manley (Wellso & Manley 2007) has done much to improve the situation through the description of several new species and clarification of the hosts, distributions, and identifying characters of previously known species. I have benefited more than many from their work, since during the 25 years leading up to that work I had collected large numbers of specimens assignable to this group and was fortunate to have this material examined by Stan and Gary and included in the type series of most of the new species they described. Having in my collection series of nearly all of the known species in this group greatly facilitates identification of specimens received for identification and the recognition of any new species that might come my way. Notice, however, that I said “nearly” all of the known species—there were two species described in that work that I did not have examples of; C. seminole from Georgia and Florida and C. mescalero from New Mexico and west Texas. Happily, I can now say that only C. mescalero is still missing from my collection.

Chrysomoa pausiflosculosa

Chrysomoa pausiflosculosa (woody goldenrod) | Emanuel Co., Georgia.

Chrysobothris seminole is unique in the group by its association not with deciduous hardwood trees, but rather the stems and root crowns of living woody goldenrod (Chrysomoa pauciflosculosa), a member of the aster family (Asteraceae). This plant is not a true goldenrod (genus Solidago), although they are in the same family, but is named such for the profusion of yellow inflorescences that appear during fall and resemble those of goldenrod. However, unlike goldenrod, woody goldenrod is a perennial plant with a woody root crown and stems from which new growth emerges each year. Woody goldenrod is restricted to coastal dunes and sand scrub habitats in the U.S. southeastern coastal plain, although the beetle itself has only been found in a few locations in Florida and southeastern Georgia. The beetle was first collected in numbers by Roy Morris and Edwin Donaldson, who reared adults from woody goldenrod root crowns they had collected in an effort to rear adults of another wood-boring beetle; this one in the family Cerambycidae and also undescribed and restricted to woody goldenrod. That beetle was recently described as Crossidius grahami Morris & Wappes, 2013.

Chrysobothris seminole

Adults are found primarily on lower stems of living plants.

In late May of this year, I made the 13½-hour drive from St. Louis to Emanuel Co., Georgia to visit the type locality of C. seminole and try my hand at finding this species. Along the way I met up with two excellent beetle collectors in Tennessee; Joshua Basham and Nadeer Youssef. Josh and Nadeer are among the few people who have succeeded in collecting this species, having visited the type locality during the previous two years and managing to collect a small series of adults. Their experience proved to be invaluable, as we saw only three individuals during our two days in the area. Josh saw the first soon after we arrived at the type locality and was kind enough to let me see it in situ on its host plant and make the collection, and Nadeer was equally kind to give me the third individual we saw. Our consensus was that a combination of early timing and lack of rain was the reason for their scarcity, and to hedge our bets we collected a number of plants that showed evidence of buprestid (as well as cerambycid) larval workings in the lower stems and root crowns to attempt rearing additional specimens. Because of their scarcity, I kept the adults alive and photographed them later that night in a more secure “studio” setting, and while this species has been photographed before I do believe that the photographs presented here are the only photos of live individuals.

Sand scrub habitat | Emanuel Co., Georgia.

Sand scrub habitat | Emanuel Co., Georgia.

In addition to its unique host plant association and restricted distribution, C. seminole can be distinguished from other members of the C. femorata species-group by both sexes having the frons and clypeus uniformly brown (in most other species of the group the frons and clypeus are variously colored, often brightly so in males of the species). The one other species with both males and females also exhbiting a uniformly brown frons and clypeus is C. mescalero (now the only species still lacking in my collection), which Wellso & Manley (2007) distinguished from C. seminole by having three distinct elytral costae (C. seminole has two indistinct costae), its indistinct elytral foveae (in C. seminole the foveae are distinct), and its southwestern distribution and association with oaks. I suppose now I’ll have to start making plans for a June/July visit to sand dune habitats in New Mexico and west Texas sometime in the near future.

REFERENCES:

Morris, R. F., II & J. E. Wappes. 2013. Description of a new Crossidius LeConte (Coleoptera: Cerambycidae: Cerambycinae: Trachyderini) from southern Georgia with comments on its biology and unusual distribution. Insecta Mundi 0304:1–7 [pdf].

Wellso, S. G. & G. V. Manley. 2007. A revision of the Chrysobothris femorata (Olivier, 1790) species group from North America, north of Mexico (Coleoptera: Buprestidae). Zootaxa 1652:1–26 [abstract].

© Ted C. MacRae 2014

Who likes mole crickets?

Who likes mole crickets?

Who likes mole crickets?

Scapteriscus borellii

I do!

On a recent collecting trip to southeastern Georgia, we spent the night in Swainsboro. We found a hotel and went to the restaurant across the street for dinner. It was dark by the time we got back to the hotel, and since it was a rather warm, muggy night we did what any entomologist worth his salt would do on such a night—creep around the parking lot and building perimeter checking the lights for insects. Late May is still a tad early for checking lights, but among the small assortment of insects we did find were these slim, active insects known as mole crickets (family Gryllotalpidae). Not true crickets, though related, and certainly not moles, these odd-looking critters are immediately distinguishable by their mole-like, fossorial (digging) front legs—a remarkable example of convergence between members of two completely separate animal phyla.

Scapteriscus borellii (southern mole cricket) | Emanuel Co., Georgia.

Scapteriscus borellii (southern mole cricket) | Emanuel Co., Georgia.

Rather than fiddle with them out in the parking lot, I decided to bring them inside for studio photographs on a clean, white background. The widely separated tibial dactyls (literally, “shin fingers”) of the digging feet identify them as Scapteriscus borellii, or southern mole cricket. Despite their name they are an exotic insect, having originally come from much further south (southern South America) and arriving in the U.S. early in the 20th century. While true crickets jump, mole crickets run—and fast! They also, however, have the comical tendency to play dead for a moment when disturbed before bolting to safety. I was able to use this behavior to my advantage while taking photographs—every time he began running, all I had to do was cover him up with a bottle cap. After only a few seconds I was able to remove the cap and take a shot or two before he got the nerve to try to bolt again.

© Ted C. MacRae 2014