PROC. ENTOMOL. SOC. WASH. 89(3), 1987, pp. 571-580 SYSTEMATIC NOTES ON UROPHORA (DIPTERA, TEPHRITIDAE) SPECIES ASSOCIATED WITH CENTAUREA SOLSTITIALIS (ASTERACEAE, CARDUEAE) AND OTHER PALAEARCTIC WEEDS ADVENTIVE IN NORTH AMERICA Ian M. White and Stephen L. Clement (IMW) CAB International Institute of Entomology, 56 Queen's Gate, London, SW7 5JR, United Kingdom. (SLC) United States Department of Agriculture, Biological Control of Weeds Laboratory (Rome, Italy), American Embassy, Agriculture, APO New York 09794, USA; Present address: USDA, ARS, Regional Plant Introduction Station, 59 Johnson Hall, and Department of Entomology, Washington State University, Pullman, Washington 99164-6402. Abstract.— T\iQ choice of Centawea solstitialis plants of differing origin by Urophora jaculata and U. sinmaseva is described and the distribution of the flies is mapped. A key is provided to separate U. jaculata and U. sinmaseva from other species of current interest to North American weed biocontrol projects, namely U. cardui, U. jaceana, U. quadri-faciata, U. solstitialis and U. stylata. The identity of each species was verified by com-parison with type specimens. A lectotype is designated for U. jaculata Rondani. Three species of Urophora Robineau-Desvoidy (Diptera: Tephritidae) are asso-ciated with Centawea solstitialis L. (yellow starthistle, YST or St. Barnaby's thistle) in the Palaearctic region, namely U. jaculata Rondani, U. sirunaseva (Bering) and U. quadrifasciata (Meigen). Yellow starthistle {Centaurea solstitialis) is widespread in the Mediterranean area (Dostal, 1976; Wage-nitz, 1975), southern European USSR (Bes-sarabia, Black Sea coast, parts of the Dnie-per and Don valleys, Crimea, Armenia and Caucasus) (Cherepanov, 1 963), Iraq and Iran (Wagenitz, 1980). Yellow starthistle is ad-ventive in western and central Europe, North and South America, South Africa, Austra-lia, and New Zealand (Dostal, 1976; Mad-dox, 1981; Maddox et al., 1985; Maddox and Mayfield, 1985). In western United States yellow starthistle is a noxious weed that infests over 3 million hectares of land. especially rangeland. There is considerable interest in using phytophagous arthropods from the Palaearctic region for its biological control (Maddox and Mayfield, 1985; Mad-dox et al., 1985). Moore (1972) lists a fur-ther 28 species of Centaurea (sensu lato) that occur in North America, only two of which are native; the remaining species are all adventive weeds of Palaearctic origin. A seedhead fly from Italy, named as " U. sirunaseva,"" was the first biological control agent found safe to introduce into western U.S. for yellow starthistle control (Zwolfer, 1969; Sobhian and Zwolfer, 1985), but in-troductions of this fly into California in 1969, 1976 and 1977 did not lead to its establishment (Maddox, 1981;Julien, 1982; Sobhian and Zwolfer, 1985). This failure to establish on Califomian populations of yel-low starthistle was attributed to host-plant incompatibility, because "the fly would ovi-
Systematic notes on Urophora (Diptera, Tephritidae) species associated with Centaurea solstilialis (Astreraceae, Cardueae) and other palaearctic weeds adventive in North America
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