S. Mahunka szerk.: Folia Entomologica Hungarica 34/1. (Budapest, 1981)

day 223, and finally on 17 September 922 individuals. In 1967, albeit the number of F. intonsa was lower in general, it was still increasing by the end of August and in September. The last highest incidence of thrips was observed on 26. September, after this date some thrips were still caught till 11 October. Again, mass flights were preceded by rising mean daily temperatures. On the days of mass flights the mean air temperature was between 16 and 21°C, with a max. of 21° C. The peak autumn flight of F

. intonsa, observed at Keszthely, must have been in connection with seeking of overwintering sites (JENSER, 1973). Flight of Thrips minutissimus females started relatively early and at low temperatures. For the first time, when a considerable number of specimens was captured (April 29, 73 thrips), the mean air temperature was 13.4°C, with a maximum of 18,6°C. On the next days of similar temperature conditions, no flight was noted. Following a short period of cooling down, there was a fast warming up and the mean air temperature was between 14.6 and 16.1°C, while the maximums reached 21 to 25°C. The number of captured thrips (380 specimens per 3 days) on the first days of May, coincided with the steep temperature rise. In spite of next days' similar temperature conditions, only a few T. minutissimus appeared. From mid-May there was no flight at all. In 1965, no mass flight was observed. In agreement with the data of LEWIS (1964) the mass flights coincided with the formation of anticyclonic weather conditions. However, the mass flight of T.minutissimus occured under relatively low temperatures, not falling into the average flight characteristics. No mass flights of species belonging to the families of Aeolothripidae and Phlaeothripidae were observed during the two-year-long operation of the suction trap, at Keszthely. These data are consistent with those of LEWIS (1963, 1964, 1965). However, some species' occurrence in relatively low frequencies was noted for a longer time period. Individuals of Aeolothrips interme- dius Bagnail were caught from the beginning of May through the end of September. During this interval at most 1 to 3 individuals were captured per day. Among the species of Phlaeothripidae family Haplothrips aculeatus (Fabricius) was collected by the trap between late July and late August. A maximum number of 10 individuals per day was captured (KLIMT, 1971). Among the species collected by suction trap, the following species proved to be new to the Hungarian fauna: Baliothrips vittipennis Bagnall (JENSER, 1976), Neoheegeria hamanni Priesner, Phlaeothrips bispinosus Priesner, Hoplothrips fungi Zetterstedt, H. grisescens Priesner, H. longisetis Bagnall, H. semicaecus Uzel (KLIMT, 1971). A cknowledgements I feel indebted both to Dr. T. JER MY for generously supplying the Thysanoptera material and for his advice, and to Dr. Z. MÉSZÁROS for help in evaluating the meteorological data. REFERENCES JENSER, G. (1973): Observation on the autumn mass flight of Frankliniella intonsa Trybom (Thysanoptera, Thripidae). - Acta Phytopathologica, 8/1-2/: 227-230. JENSER, G. (1976): Magyarország faunájára uj Thysanoptera fajok. - Folia ent.hung., 29: 39-41. JOHNSON, C.G. (1950): A suction trap for small airborne insects which automatically segregates the catch Into successive hourly samples. - Ann.appl.Biol.

, 37: 80-91. KLIMT, K. (1971): Faunitisch-systematische Studien an ungarischen Phlaeothripiden (Thysanoptera). - Folia ent.hung., 25: 47-66. LEWIS, T. (1963): The effect of weather on emargence and take-off of overwintering Limothrips cerealium Haliday (Thysanoptera). - Ann.appl.Biol.

, 51: 489-502. LEWES, T. (1964): The weather and mass flight of Thysanoptera. - Ann.appl.Biol., 53: 165-170. LEWIS, T. (1965): The species, areal density and sexual maturity of Thysanoptera caught in mass flights. - Ann.appl.Biol., 55: 219-225. TAYLOR, L.R

. (1951): An improved suction trap for insects. - Ann.appl.Biol.

, 38: 582-591. Author's address: Dr. G. JENSER Research Institute for Fruit-growing and Ornamentals H-1775 Budapest P.O.B. 108 Hungary