Location: Systematic Entomology Laboratory
2018 Annual Report
Objectives
ARS is interested in performing research to increase and enhance understanding of the systematics of flies (Diptera) important to agriculture and the environment, especially fruit flies, leaf-mining flies, tachinid flies. We will develop new identification tools (descriptions, diagnoses, molecular markers, illustrations, keys and computer identification systems), determine the correct names of species and higher taxa, and elucidate the relationships (phylogeny) and classification of select groups of these flies, which include invasive crop pests, parasitoids of plant pests, and potential biological control agents for weeds. The objectives of our project are: 1) Investigate the taxonomy and natural history of fruit flies; analyze species concepts, develop diagnoses, descriptions, illustrations and identification tools, biosystematic databases, determine host plants, and analyze phylogenetic relationships; 2) Conduct molecular systematic and ecological analysis of pest leaf-mining, galling, and fruit flies, and their parasitoids, including sequencing of DNA of previously unstudied species, development of diagnostic tools, discovery of possible cryptic species and host races, and analysis of phylogenetic relationships; 3) Investigate taxonomy of tachinid flies and other higher flies; analyze species concepts, develop diagnoses, descriptions, illustrations and identification keys, and analyze phylogenetic relationships; and 4) Provide scientific identifications of plant-feeding and other agriculturally important flies.
Approach
ARS will undertake research to generate morphological and molecular characters (DNA sequences) that will be used to test species concepts and hypotheses of relationship among agriculturally important flies and parasitoid wasps that attack them. These data also will be used to develop new diagnostic tools (descriptions, illustrations, keys) to permit more rapid and accurate identification of these flies and wasps. Databases containing scientific names, distributions, taxonomic literature, and host plant and specimen data pertaining to fruit flies will be expanded and disseminated to the user community. These and other taxonomic tools will be made accessible to the public via publications, the internet, and other electronic media. Timely and accurate identifications of flies will be provided, including those intercepted at ports-of-entry by APHIS-PPQ or submitted by a wide range of scientists and regulatory agencies, and portions of the National Collection in the National Museum of Natural History, a vital tool for research and identification, will be maintained and expanded.
Progress Report
Taxonomy and natural history of fruit flies. Accomplishments on the taxonomy of the largest and most economically important group of fruit flies (Anastrepha) in the American tropics included publication of new molecular markers to distinguish multiple pest species, publication of new distribution and taxonomic data for 60 species (including first records of 33 species from Colombia), description of the immature stages of three species, further development of an electronic identification tool for the more than 300 species of this group, and collection of thousands of additional samples for DNA analysis. Two studies of the fly biodiversity in Costa Rica were published. A checklist of the largest and most economically important group of fruit flies in Africa, Asia and Australia was published. Data from additional publications were added to names and host plant databases for fruit flies, and progress was made to serve this information on an APHIS-CPHST web site. This information is critical to APHIS-PPQ and other regulatory agencies to prevent the spread of pest species into the U.S.
Molecular systematic and ecological analysis of pest leaf-mining, galling, and fruit flies, and their parasitoids. Additional primers necessary for DNA sequencing were designed for both mitochondrial and nuclear genes in a variety of plant-feeding groups of flies and their associated parasitoids. These specialized primers have been designed for leaf-mining flies (Liriomyza, Phytomyza) that are pests of fruit and vegetables, fruit flies (Blepharoneura) that breed in relatives of pumpkins, cucumbers and squash, and for braconid and other wasp parasitoids attacking these groups. Molecular analysis of the evolutionary radiation of fruit flies (Blepharoneura) was published. Data collection continued on genetic variation and distribution of globally invasive leaf-mining pests (Liriomyza) of vegetable crops in order to better understand species limits, ecological interactions, and host ranges of the plant pests and their parasitoids. This information is critical to effective management of pest populations as well as to APHIS-PPQ and other regulatory agencies working to prevent the spread of pest species into the U.S.
Taxonomy of tachinid flies and other higher flies. The scientist responsible for this objective retired and the position is vacant.
Scientific identification of agriculturally important flies. In the period from October 1, 2017 to June 13, 2018, 2,012 submittals (7,690 specimens) were identified, including 405 "urgent" submittals for USDA-APHIS-PPQ of specimens intercepted on perishable commodities at ports-of-entry.
Accomplishments
1. Protecting American agriculture from pest fruit flies. True fruit flies include some of the most important pests of commercial fruits. Of the 5000+ currently known species, more than 100 are agricultural pests, attacking commercial and subsistence crops including citrus, mango, peach, apple, and many others. Many species are invasive and threaten U.S. agriculture. Current identification capabilities are based mainly on adult morphology, sometimes of only one sex, and the larvae, the stage most commonly intercepted at ports of entry, are difficult if not impossible to identify. Scientists from USDA-ARS Beltsville, Maryland, USDA-APHIS-CPHST, Department of Agriculture from California and Florida, several universities, and international collaborators are working to develop new diagnostic tools to more rapidly and reliably identify all life stages of fruit flies, by studying the morphology and DNA of the adults and larvae demonstrated the utility and limits of DNA barcodes (a particular DNA region commonly used for identification) as a diagnostic tool. Four major pest species can be identified using DNA barcodes, but other pests cannot be distinguished. This new information already is being used by USDA to identify specimens captured in detection programs and at ports of entry and is extremely valuable to regulatory agencies such as APHIS-PPQ in limiting the spread of fruit fly pests.
Review Publications
Borkent, A., Brown, B.V., Adler, P.H., Desouza Amorim, D., Barber, K., Bickel, D., Boucher, S., Brooks, S.E., Burger, J., Capellari, R.S., Costa, D.N., Cumming, J.M., Curler, G., Dick, C.W., Epler, J.H., Fisher, E., Gaimari, S.D., Gelhaus, J., Grimaldi, D.A., Hash, J., Hippa, H., Ibáñez-Bernal, S., Jaschhof, M., Kameneva, E.P., Kvifte, G.M., Lonsdale, O., Marshall, S.A., Mathis, W., Michelsen, V., Naglis, S., Norrbom, A.L., Pape, T., Pereira-Colavite, A., Pollet, M., Runyon, J.B., Savage, J., Silva, V.C., Sinclair, B.J., Swann, J., Vilkamaa, P., Whitworth, T., Woodley, N., Zavortink, T.J., Zumbado, M.A. 2018. Remarkable fly (Diptera) diversity in a patch of Costa Rican cloud forest: Why inventory is a vital science. Zootaxa. 4402:53-90.
Gagne, R.J., Ley-Lopez, J.M., Hanson, P.E. 2018. First new world record of a gall midge from palms: a new species of Contarinia (Diptera: Cecidomyiidae) from Geonoma cuneata in Costa Rica. Proceedings of the Entomological Society of Washington. 120(1):51-61.
Brown, B.V., Borkent, A., Alder, P.H., Amorim, D., Barber, K., Bickel, D., Boucher, S., Brooks, S.E., Burger, J., Burington, Z.L., Capellari, R.S., Costa, D.R., Cumming, J.M., Curler, G., Dick, C.W., Epler, J.H., Fisher, E., Gaimari, S.D., Gelhaus, J., Grimaldi, D.A., Hash, J., Hauser, M., Hippa, H., Ibanez-Bernal, S., Jaschhof, M., Kameneva, E.P., Hash, J., Hauser, M., Kerr, P.H., Kormeyev, V., Korytkowski, C.A., Kung, G., Kvifte Mikalsen, G., Lonsdale, O., Marshall, S.A., Mathis, W., Michelsen, V., Naglis, S., Norrbom, A.L., Paiero, S., Pape, T., Pereira-Colavite, A., Pollet, M., Rochefort, S., Rung, A., Runyon, J.B., Savage, J., Silva, V.C., Sinclair, B.J., Skevington, J.H., Stireman, J.O., Swann, J., Vilkamaa, P., Wheeler, T., Whitworth, T., Wong, M., Wood, D., Woodley, N., Yau, T., Zavortink, T.J., Zumbado, M.A. 2018. First comprehensive inventory of a tropical site for a megadiverse group of insects, the true flies (Diptera). Communications Biology. 2018(1):1-21.
Doorenweerd, C., Leblanc, L., Norrbom, A.L., San Jose, M., Rubinoff, D. 2018. A global checklist of the 933 fruit fly species in the tribe Dacini (Diptera: Tephritidae). ZooKeys. 730:17-54.
Gagne, R.J. 2018. Key to adults of North American genera of the subfamily Cecidomyiinae (Diptera: Cecidomyiidae). Zootaxa. 4392(3):401-457.
Barr, N., Ruiz-Arce, R., Farris, R., Silva, J.G., Lima, K., Dutra, V., Ronchi-Teles, B., Kerr, P.H., Norrbom, A.L., Nolazco, A.N., Thomas, D.B. 2017. Identifying seven Anastrepha (Diptera; Tephritidae) species using DNA barcodes. Journal of Economic Entomology. 111:405-421.
Dutra, V., Ronchi-Teles, B., Steck, G.L., Rodriguez, E.J., Norrbom, A.L., Sutton, B.D., Silva, J.G. 2018. Description of third instar larvae of Anastrepha curitis, Anastrepha pickeli and Anastrepha pulchra (Diptera: Tephritidae). Annals of the Entomological Society of America. 120:9-24.
Rodriguez Clavijo, P.A., Norrbom, A.L., Arevalo, E., Balseiro, T.F., Diaz, P., Paula, A., Montes, J., Benitez, M., Cruz, M., Rodriguez, E.J., Steck, G.J., Sutton, B.D., Quisberth, E., Lagrava Sanchez, J.J., Colque, F. 2018. New records of Anastrepha (Diptera: Tephritidae) primarily from Colombia. Zootaxa. 4390(1):1-63.
Winkler, I., Scheffer, S.J., Lewis, M.L., Ottens, K.J., Rasmussen, A.P., Gomes-Costa, G.A., Huerto Santillan, L.M., Condon, M.A., Forbes, A.A. 2018. Anatomy of an adaptive radiation: Blepharoneura fruit flies. BMC Evolutionary Biology. 18:30-33.
Martinez-Alva, J.O., Sema, F., Norrbom, A.L. 2017. New records of Rhagoletis (Diptera: Tephritidae) in Colombia, with discussion on the morphological variations of some species. Zootaxa. 4273:549-558.
