Towards a World Monograph of the Therevidae

18-19 July 1996
University of Illinois at Urbana-Champaign

The meeting convened at 8 AM with Michael Irwin chairing. Present were Ev and Marion Schlinger (Schlinger Foundation); Brian Wiegmann (North Carolina State University, and co-PI) and his graduate student, Longlong Yang; Chris Thompson (USDA Smithsonian Institution, consultant) Don Webb (Illinois Natural History Survey, collaborator); Steve Gaimari, Kevin Holston, and Mark Metz (graduate students with Mike Irwin, UIUC); Gail Kampmeier (INHS/UIUC, collaborator); Maya Patel (graduate student at UIUC, illustrator); also visiting were Ed Armbrust (Director, Center for Economic Entomology, INHS), May Berenbaum (Head, Department of Entomology, UIUC), and Christine Armer (graduate student, UIUC). Unable to attend were David Yeates (co-PI) and his graduate student, Shaun Winterton, from the University of Queensland, Australia. Additions to the agenda were solicited after introductions were completed.

Accomplishments on the PEET Grant

Database Capture and Management. Gail Kampmeier gave a presentation of the databases that were being used to capture label information on therevid specimens from museums and collections from around the world. Thus far 20,650 specimens in over 4,200 lots have been recorded in the database, with the initial concentration being those specimens from Australia. The specimen-related databases require minor fine-tuning, and participants were encouraged to think of the types of outputs they would like to see from the databases for their use and for queries on the WWW. Needing major input for revamping were those databases primarily concerned with literature. The existing databases focusing on literature were demonstrated and discussion on the second day will result in a major overhaul in the way these databases function.

All of the databases feature on-line context sensitive (both field- and database-specific) and general help. Questions about anything in the databases are tracked on-line, date and time-stamped, and marked with whether the question has been resolved. Unanswered questions were circulated to attendees in an attempt to resolve them.

An outline of the presentation appears in Appendix A.

Cladistics of the Therevid Project.
Morphology Mike Irwin gave an overview of family and subfamily phylogeny from the point of view of morphology. He and David Yeates have completed a detailed morphological analysis of the head and female terminalia including the spermatheca, which is not sclerotized in the Therevidae. They plan on completing a survey of characters of the adult, in preparation for a cladistic analysis. Maya Patel is working on the drawings for this aspect of the project and showed examples of her work to the group.

Molecular Analysis Brian Wiegmann explained the steps taken when he receives a fly in 95-100% ethanol from someone in the group.

1) The entire fly is ground in ca. 50 µl of buffer to extract the DNA. Many types of DNA and RNA are extracted, all of the following are potential sources of variation for phylogeny: nuclear DNA, mitochondrial DNA, mRNA, rRNA, and tRNA.

2) extract is then preserved at -80° and used a few µl at a time in various tests. It is important to keep everything cold as RNA degrades more easily than DNA

3) use primers to tag gene sequences and PCR (polymerase chain reaction) to amplify the gene sequence of choice. 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 are different from other orders at this gene, but families of flies are little different from one another (only 2%).
• 28s rDNA — looks more divergent than 18s
• EF1 a = elongation factor 1 a — used for noctuids in Maryland
• DDC = dopadecarboxylase — 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 oxydase I & II
• 16s rDNA

By the end of summer, Brian expects to know the utility of the above genes to delineation of the Therevidae. He is searching for a gene or genes with about a 25% mutation rate (1 in 4 of the bases making up DNA could change) that would allow a maximum amount of change before saturation occurs.

4) run agarose gels to clean up the system and isolate one or more genes

5) sequencing step: no longer using radiolabelling but fluorescent marking that can be read by a new ABI automated sequencer, on which data are read and collected directly onto a computer.

These basic steps can be learned in a week or so. Now the researchers can spend more time looking at the systematics rather than at the biochemistry of the process.

Preservation of Material for Molecular Studies. Brian Wiegmann’s lab has been conducting experiments to find best methods for preservation of material for subsequent molecular analysis. What works best is followed by less successful methods in descending order:

1) live fly into liquid nitrogen or in -80° freezer, if used soon; add cold 95-100% ethanol if not to be used right away

2) live fly into 95-100% cold ethanol (do not bake in car, put in cooler on ice if possible)

3) live fly into 70% ethanol

4) recently dead fly into 70% ethanol

5) museum specimens in 70% ethanol — only a small percentage of these work

6) dried specimen — works only for some abundant genes (mitochondrial and ribosomal genes) when specimens have been handled well (humidity is not high)

They have also experimented with cyanide-killed specimens. If the specimens are left in the cyanide tube, they got great gene amplification because the cyanide acted as a desiccant. They have yet to test killing with cyanide and quickly moving the specimen to 95-100% ethanol.

Taxonomic Monographs. Mike Irwin’s group hopes to develop a monograph of the Nearctic Therevidae within the first 5 year period, with graduate student Steve Gaimari working on Ozodiceromyia (Cyclotelus-group), Kevin Holston working on Thereva (Thereva-group), and Mark Metz on Brachylinga (Brachylinga-group). The first and third groups have north-south distributions, while the second group is distributed east-west. Don Webb and Mike Irwin will be working on smaller genera and they have completed revisions of 7 genera since 1990.

Mike Irwin and David Yeates will visit Leif Lyneborg (collaborator in Copenhagen) for about a week in September 1996 after the International Congress of Entomology. They will be working on the speciose Australian genus Anabarrhynchus.

Ozodiceromyia This genus has 30 currently described species. Steve Gaimari has identified 18 easily sortable groups, finding about 60 species so far in the 9 groups he has sorted to species without dissection of the external genitalia. He estimates he will find 100-150 species, and it will take him about 2 months to get a working idea of all the species. He will be going to Europe and Russia in September and October to study types. He will be trying to test the phylogenetic relationships among species groups and his first paper will be a key to and description of species groups and 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 morphology. The question was raised if he would also include SEM work on morphological structures, to which the general answer was that he would use all the tools helpful in illustrating his papers, including SEM.

Brachylinga There are 16 species of Brachylinga currently described. Mark Metz has sorted out 36 species groups and thinks he will have a maximum of just over 100 species. This genus is considered to be all New World, 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 would like to publish on the problem of female specimens that are not associated with males through a morphometric analysis of the lock & key mechanism to associate males and females. Secondly, he and Mike Irwin will describe a specimen found in amber from the Dominican Republic.

Thereva There are 184 recognized species of Thereva in the literature and synonymies and homonymies abound. Kevin Holston went to the literature first and found that even in the literature there are several species complexes described. He will be looking at the relationship between regions. Lyneborg will be of considerable help to Kevin’s work when analyzing the Palearctic species.

World Wide Web and Dissemination. Gail Kampmeier showed the therevid home page and explained that many areas are not much more than a skeleton that needs some informational meat. She will be working with Brian to link the pages to the Tree of Life (Brian is in charge of the Diptera with David Yeates).

Chris Thompson showed the Diptera pages (http://www.sel.barc.usda.gov/Diptera/diptera.htm) associated with his group at the Smithsonian. Their site too is remains under construction, but their graphics are quite beautiful.

Chris also demonstrated his Fruit Fly Expert System and Biosystematics Information Database on CD-ROM.

In-depth Discussions

Needs for Molecular Studies. Brian Wiegmann would like to see at least two species preserved from each genus to get a good estimate of the ancestral node. See earlier discussion for the best means of preserving specimens for molecular studies. The greatest needs for fresh material lie in the Apsilocephala-group and the Phycinae.

Expedition Planning.

The following areas were identified for potential expeditions (supported by external funding):

• Southern Africa Indian Ocean coast near Mozambique; Western Cape particularly Namaqualand; Namibia; Botswana. ideal timing: 6 weeks between September and November
• Chile-Argentina ideal timing: 6-8 weeks between October and December
• Tasmania ideal timing: 2 weeks between November and February
• Central Asia/China Longlong Yang will help make contacts and plans for this expedition. ideal timing: 4 weeks between late June and August
• Madagascar quick initial trip (ideal timing: June) to develop logistics plus longer trip (ideal timing: June)
• Central America ideal timing: July-August
• South Florida & Caribbean Keys; Dominican Republic; Cuba? ideal timing: February
• Atlas Mountains & Saharan Desert (NW Africa) ideal timing: April-May
• New Caledonia ideal timing: September-October
• Baja California/Mexico ideal timing: March/April-June
• Indian subcontinent Nepal; Pakistan; SW coast of India. ideal timing: unknown
• New Guinea ideal timing: unknown

Tentative plans through 1998:

• late October-November 1996: southern Africa
• Spring Break (March 1997): Northern Baja California — likely that Longlong Yang will come to Irwin lab before and after this expedition to learn more about therevid morphology, join collecting trip, and curate catch afterward.
• June 1997 : Mike Irwin and Schlingers (and perhaps Chris Thompson) to scope out logistics of larger proposed expedition to Madagascar
• July-August 1997 : Central America
• October-November 1997 : Chile and Argentina
• summer 1998 : Gobi Desert; China; inner Mongolia

All researchers planning trips should include trips to museums to not only look at their specific group(s), but look through unsorted Diptera for unidentified therevids.

Because students may be in classes and others may have other commitments, not all will be able to go on all of the expeditions. Shaun Winterton should plan on attending at least one expedition, possibly combining it with a trip to the States to visit the laboratories of Irwin and Wiegmann.

Needs and Changes to Databases.

• attach codes for biogeographical regions to the lots database
• break Argentina, Brazil, Chile, and South Africa down to state in polregns (political/biogeographic regions) database.
• include other types of zones in biogeographical regions database
• add a history of determiners for specimens rather than the last determiner
• workers should take a PowerBook with the database structure with them when they visit museums to input data from specimens they will be unable to borrow from the museum.
• add tag to identify potential economic importance of various taxa, even though at the moment, most will be “potential” contributors to the biological control of fossorial arthropods.
• consider adding a tag for threatened and endangered status to taxa (currently this information is unknown)
• add GenBank access# portal to specimens
• add compound deposit codes (museums database) to reflect multiple holdings of parts of the same specimen, such as part for molecular analysis and part for morphological studies.
• add category under preservation for molecular studies of “in 95-100% ethanol in ultrafreezer”
• use semicolons between authors names in Reprints database and always put the author with the surname first and initials later for easier parsing.
• consider combining the title, journal and/or book titles into a single field named “source” and the volume and page information into a single field named “collation”
• add fields for exact date (day, month, year) for publication because of its potential importance in determining precedence. Literature with only a year are considered in precedence matters to have been published 31 December of that year. Neil Evenhuis is currently putting together publication dates for much of the known systematic literature.
• in Reprints database, add the ability to print the full journal title in the citations layout if the abbreviated title is not present.
• split up the taxa database into hierarchy of Valid Taxon Names to Names to instances where these names are used (literature; specimens)
• add a field for titles in a non-romanized language when the international cross-platform standards are available and accepted.
• add fields for type information that is associated with the taxa database that will tell where the types are deposited and whether they still exist.
• find an automated way to get to the synonymy/homonymy tables

Outreach. The suggestion was made to press a CD-ROM to update regular users of the databases. Gail Kampmeier will be investigating how to best query the databases from the WWW and hopes to have this feature available by the end of 1996. She will also be working on updating the WWW therevid pages and with Brian Wiegmann’s help, linking to the Tree of Life, and developing materials according to that site’s format.

Barbecue at Irwin’s

Bonnie and Mike Irwin hosted a potluck barbecue on Friday evening to celebrate the successful two-day gathering of PEET participants on the therevid project. It was a wonderful cap to a very productive meeting!