1998-1999 Therevid Expeditions

Madagascar (9-25 April 1998)

U.S. Southwest (June-July 1998)
In 1998 Mr. Metz returned to the southwestern U.S. to add a third year of data for the morphometric study on male and female genitalia of Ozodiceromyia nanella (Cole). As with previous years, after setting up a 6m Malaise trap in Fort Wingate, New Mexico to collect from the same population, Mr. Metz chose a target area to mine for new taxa and new collection records. This year he traveled to the southeast corner of Utah to target some areas that had previously been under collected or not collected at all.

He hand and Malaise trap collected in areas near Bluff, Spring Creek in the Manti-La Sal National Forest, Newspaper Rock, and just outside of the southeastern boundary of Canyonlands National Park. His collecting ended early when a northwest weather system moved in and forced an early evacuation of the area due to snow. The results of this short collecting period were no new taxa from the area, but new collection records. A minor behavioral note made by Mr. Metz is that therevids don't seem to gather at saline water sources. The southern border of Utah is dominated by the San Juan River system, which is fed by many saline alluvia. Small rivulets of water are normally hot spots for therevid collecting, but they seemed to avoid any water sources rich in mineral salts.

To maximize the time in the field, Mr. Metz traveled south and west to continue collecting and sampling for therevid diversity. He traveled as far west as Kelso Dunes, California, continuing to sample. Again, no new species were collected.

The goals of the trip were met when Mr. Metz returned to the Fort Wingate site to find that he had hundreds of O. nanella. In addition, from a cursory examination, the 1998 O. nanella population sample was heavily infested with microtrombodiid mites. The disproportionate parasitization rate on therevids by microtrombodiid mites compared to other Diptera was a discovery made from last year's sample.

Colorado (July 1998)
Mike Irwin traveled to Fort Collins, CO for two days in July 1998. He met up with Scott Fitzgerald, who is now a graduate student at Oregon State University. In the hills above the Center for Disease Control buildings in Ft. Collins, they completely tore apart a woodrat's nest, sieved the contents for larvae, and managed to secure about 10 during the 2-day job. They sought larvae of Apsilocephala. Unfortunately, when the larvae pupated and eventually eclosed, they turned out to be Scenopininae.

New Caledonia (11-25 November 1998)
Michael Irwin, Ev and Marion Schlinger, and Don Webb returned to New Caledonia seeking males of species previously only known from female specimens. Collecting was poor, with exceptionally heavy rains most of the time. Only a few therevids were collected, all females, and they are preserved in 95% ethanol. Some will be used for molecular studies. Two females of a species and genus were collected that were only known from one previously collected female. The unfortunate fact is that we were unable to gather males of any of the three genera discovered on that island. We will have to return in the future if we hope to be able to describe these very critical new genera. One malaise trap was left in a forest on Mt. Koghi and is being maintained by Ms. Nathalie Marry. She has sent us one set of six samples from the trap.

Brisbane Forest Park (August-Dec. 1998)
Sites close to the Queensland University laboratory in Brisbane Forest Park were visited a number of times during spring and early summer. A number of genera of Therevidae were taken live and transported to the laboratory for macro photography.

Mt. Walsh (4-6 Dec. 1998)
Mt. Walsh is a prominent hilltop location approximately 250 km north west of Brisbane, Australia. The peak was scaled on two consecutive days and numerous asiloids were collected, including a small number of Therevidae.

California (mid-December 1998)
Mike Irwin spent about two days collecting larvae in coastal dunes and on inland sandy hillsides during mid-December 1998. Over 80 larvae were collected. As of this writing, two have pupated and emerged: a male Ozodiceromyia and a male Nebritus. Both were preserved in 95% ethanol for molecular analysis.

Tasmania (11-20 Dec. 1998)
David Yeates and Shaun Winterton traveled to Tasmania in mid-December to collect Therevidae. We had the pleasure of Lisa Bautin's company (Wellington, NZ) on the expedition as well. Lisa's work is also funded by the Schlinger foundation and she was searching for spiders, acrocerids, and advice on setting and servicing malaise traps. The special goal of the expedition was to obtain fresh material of the fly genus Clesthentia White. This endemic Tasmanian genus was described at the turn of the century and has rarely been collected since. It has recently been removed from the Therevidae and placed in the near-therevid family Apsilocephalidae. Recent collections of this genus will allow us to obtain DNA samples from the genus and help us assess the phylogenetic position of the Apsilocephalidae with respect to the Therevidae.

Tasmania's December weather can be fickle, but we were blessed with fine, sunny conditions for all but one day. The first day of the expedition was a heat wave in Hobart, with temperatures above 38°C. Collecting was restricted to the known range of Clesthentia in the eastern half of Tasmania. Many therevid specimens were hand collected and malaise traps were set in various habitats and left in place to be serviced by another UQ systematics lab Ph.D. student Jeff Skevington who visited Tasmania from 20th Dec 1998-16 January 1999. The malaise traps therefore will have about 1 month of active collecting time, and are still in the field at the time of writing this report.

Hand collecting was very successful with almost 200 specimens taken belonging to an estimated 19 species in 13 genera. The best news was that we were successful in obtaining specimens of Clesthentia. We visited the type locality near Hobart and collected specimens in an abandoned farm building. This indicates that the natural habitat in the field is probably cave entrances or overhangs and explains the scarcity of specimens in collections. Specimens will be dispatched to Wiegmann's lab at North Carolina State as soon as possible for DNA extraction and sequencing.

Western Queensland (31 Dec. 1998-9 Jan 1999)
David Yeates visited far southwestern Queensland during the first week of 1999. Malaise traps were set and hand collecting conducted in this hot, dry environment. Few therevid specimens were collected by hand netting, however preliminary analysis indicates that a number of specimens have been taken in the malaise traps, which will be serviced late in January.

Other Collecting Trips & Expeditions