1B Training. The training component of this PEET is envisioned to be primarily through the education of graduate students. Our proposal stated that we intended to train five graduate students in the science of Diptera taxonomy. All of the graduate students are now in place and actively monographing important therevid genera from around the world.

University of Illinois. The University of Illinois is training three graduate students. Two are supported through the NSF PEET grant and one is supported through matching contributions from the Illinois Natural History Survey (INHS). The INHS research assistantship was awarded to Mr. Stephen Gaimari in September 1995. Mr. Mark Metz and Mr. Kevin Holston began their assistantships in April and May 1996, respectively.

Mr. Stephen Gaimari is working on the genus Ozodiceromyia This genus has 36 currently described species. Steve has identified 18 easily sortable groups, finding 70 species to date in the 12 groups he has sorted to species without dissection of the internal genitalia. He estimates he will find more than 100 species in all, and it will take him another 2 months to get a working idea of all the species. He will be in Europe and Russia in September and October studying types. Testing the phylogenetic relationships among species groups of Ozodiceromyia will be his first task; an early paper is planned that will delineate the species groups, provide a key to and description of them, and construct a revision of the nominal O. mexicana-group. His molecular work in conjunction with Brian Wiegmann's lab will be to relate Ozodiceromyia to the rest of the Cyclotelus-group and relate this to an in-progress morphological study.
Mr. Mark Metz will be taking a number of core courses in the Department of Entomology at the University of Illinois starting this fall, but, by beginning his assistantship before the commencement of summer, he has had time to begin gathering specimens for a monographic treatment of the genus Brachylinga. There are 16 species of Brachylinga currently described. Mark has sorted out 36 morphologically distinguishable groups based on external characters and thinks he will have fewer than 100 species when his study is complete. This genus is Nearctic and Neotropic in distribution, getting as far south as Chile. Mark is reviewing the specimens before looking at the literature. In addition to publications about his chosen genus, Mark is tackling the problem of associating female specimens with males through a morphometric analysis of male aedeagal characters and the furca of females. He and Mike Irwin will also describe a therevid specimen found in amber from the Dominican Republic.
Mr. Kevin Holston began his research assistantship in early May 1996. The genus Thereva is his primary area of study. There are 184 recognized species of Thereva in the literature, and synonymies and homonymies abound. Kevin went to the literature first and found that even in the literature there are several species complexes described. He is looking at the relationships of the species between the Palearctic and Neartic Regions. Leif Lyneborg (therevid systematist in Copenhagen and collaborator on the PEET project) will be of considerable help to Kevin when assessing the Palearctic species.

North Carolina State University. Mr. Longlong Yang, of the Institute of Zoology, Academia Sinica, P.R. China, was selected as a Ph.D. candidate to investigate the higher level phylogenetic relationships of the Therevidae using nucleotide sequence data in Brian Wiegmann's lab (NCSU).

Mr. Longlong Yang began his assistantship (sponsored by matching contributions from NCSU) in July 1996 and joined Dr. Wiegmann at the first year meeting held in Urbana in late July. They returned to NCSU from Illinois with specimens of therevids collected and preserved in 100% ethanol by Irwin and others on various recent field trips. DNA extraction and PCR amplification of two key genera, Apsilocephala and Heterotropus, were successful. LongLong, in a first amplification to test the preservation of the DNA, has been successful on a number of the necessary genera in the proposed phylogenetic scheme, including Anabarynchus, Acraspisa, Efflatouniella and several additional genera.

University of Queensland. Mr. Shaun Winterton began his training on 1 July 1996 at UQ supported by Schlinger Foundation funds.

Mr. Shaun Winterton is beginning his studies by monographing the genus Noxexila (mss. name) from Australia. For his Ph.D., he will monograph the large and complex genus Agapophytus from that same region.

1C Monographic Treatments

Establishing the higher groupings. The PEET proposal stated that a higher level phylogeny for the family Therevidae was needed so that small, monophyletic groupings of taxa could be monographed. The strategy for establishing a higher level classification of the Therevidae entailed two aspects. The first was a strong, cladistic analysis based on morphological evidence, which would develop hypotheses of monophyletic units. This was to be followed by a molecular cladistic study to test those hypotheses. We felt that this would provide the most rigorous test of monophyletic units in the Therevidae.

Morphological progress. Mike Irwin and David Yeates have completed a detailed morphological analysis of the head (40 promising characters) and female terminalia (30 characters) including the spermathecae on more than 50 species in different genera of therevids scattered across the presumed spectrum of the family. Five outgroups (Asilidae, Bombyliidae, Scenopinidae [Scenopininae and Proratinae], and Apsilocephalidae) were also studied. They plan on completing a survey of characters of the adult, in preparation for a cladistic analysis. Maya Patel (graduate student finishing her M.S. in Entomology) has begun to illustrate key characters and their states for this study. Yeates and Irwin are also collaborating with Dr. Olga Ovtshinnikova (St. Petersburg, Russia) on the musculature of the male genitalia.
Molecular progress. Brian Wiegmann and Longlong Yang are using primers to tag gene sequences and PCR (polymerase chain reaction) to amplify the gene sequence of choice in selected taxa. The test taxa include Stenomphrale (Scenopinidae) and Heterotropus (Bombyliidae) as outgroups, and Parapsilocephala, Pherocera, Phycus, Henicomyia, Brachylinga, Litolinga, Thereva, and Acrosathe from the Therevidae. This is the most critical stage, and work is ongoing to determine which gene holds the most promise for the Therevidae, although ideally it is hoped that more than one marker will be identified. Genes examined or under consideration include:

• 18S rDNA -- has been useful for the oldest lepidopterans, but thus far not found to work with therevids. Diptera as a whole differ from other orders at this gene, but families of flies differ little from one another (only 2%).
• 28S rDNA -- looks more divergent than 18S
• EF1 a = elongation factor 1 a -- used for noctuids in Maryland
• DDC = dopa decarboxylase -- used for Drosophila and Aedes in the gene bank
• PEPCK = phosphoenolopyruvate carboxykinase -- used with families of lower Brachycera; very conserved
• CO I and CO II = cytochrome oxidase I & II
• 16S rDNA

By the end of summer, Brian expects to know the utility of the above genes to delineate groups within the Therevidae. He is searching for a gene or genes with up to a 25% mutation rate (1 in 4 of the bases making up DNA could change); that would allow for maximum change prior to the onset of saturation.

In the sequencing step, Wiegmann's laboratory no longer uses radiolabelling but fluorescent marking that can be read by their new ABI automated sequencer, on which data are read and collected directly onto a computer. These basic steps in the sequencing process can be learned in about a week so that researchers will be able to spend more time looking at the systematics rather than at the biochemistry of the process.

All of the specimens from Australia and Israel that were collected into 100% ethanol have now been successfully extracted and the first amplification of many genera resulted in successful preservation of the DNA.

Genus level revisions. One goal of this PEET grant is to provide a monographic treatment of the North American representatives of the entire family by the fifth year. This will entail separate monographs of the largest genera in this region: Ozodiceromyia, Brachylinga, Thereva, Pherocera, and Cyclotelus. The first three are being assigned to the graduate students, and the last two will be completed by PI Irwin.

Status of Ozodiceromyia. This large genus has been assigned to Mr. Gaimari. Original and subsequent descriptions of the 36 currently valid species in Ozodiceromyia and a listing of known repositories for their type specimens have been compiled. Most of the major museums and many of the smaller collections in the U.S. and Central America have been contacted with requests for specimens. Many of these institutions have now sent collections of the genus to us. All of the nearly 25,000 specimens currently in our possession have been labelled with loan information and unique specimen numbers, and more are being labeled as they are received on loan. Data input into the specimen databases is well underway. Gaimari has sorted and partly characterized 70 different species (in about 12 species­groups), and he and PI Irwin have worked towards developing easily identifiable species­groups for sorting this large genus. All of the specimens have been sorted at least to species-group or morphospecies, making the next stage of the revision close at hand (see below).
Status of Dichoglena, Pandivirilia, and Viriliricta. Webb and Irwin have examined Nearctic material related to these three genera, in addition to all available type specimens. The current evaluation of these three genera, in conjunction with representatives of the Palearctic species, indicates that Dichoglena and Viriliricta should be synonymized under Pandivirilia. Descriptions, keys, illustrations and distributional maps have been completed. A phylogenetic analysis of Pandivirilia, including the Palearctic material, has yet to be completed.
Status of Tabuda and Tabudamima. Webb and Irwin have examined extensive material of these two genera in addition to the type specimens. Descriptions, keys, illustrations, distribution maps and a phylogenetic analysis have been completed. This revision is in the final stage of preparation.
Status of Anabarhynchus. This speciose Australian genus is currently being monographed by Dr. Lyneborg in collaboration with PI Irwin and Co-PI Yeates. Species descriptions are nearly complete; critical illustrations have begun. Irwin and Yeates will meet with Lyneborg in Copenhagen in September 1996 to finish the manuscript.

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