Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 63. (Budapest 1971)
Kovács, L.: Data to the knowledge of Hungarian Macrolepidoptera VI. Data with respect to migrating and spreading species
Map 5. Spodoptera exigua HBN. — Annual mean of individual numbers caught by light trap The earliest specimens of S. exigua were observed rather late in Hungary, in the middle of May. The number of exemplars from May is insignificantly few, only 2 having as yet been found in the materials of the light traps, both from the southern part of the Transdanubia (Bakóca, 11 May, 1970, and Pacsa, 14 May, 1962), and both males. Along the Adriatic coast, the imagos are already regularly on the wing at this time. The next observations (2) fall a whole month later, to the middle of June. Beginning with the middle of June, how r ever, observations become regular, but individual numbers still remain rather low. There are still no more than 4 observations in the last decade of June, 6 in the first one of July, and only 10 even in the middle of the month. Any considerable increase appears for the first time merely at the end of July (37), but this is only transitional, followed by a decrease in the first decade of August (19). The second, greater and more prolonged culmination of the individual numbers, ensues in the second and third decades of August i (52 and 57, respectively). During September, the number of individuals gradually decreases (29, 20, 10 per the consecutive decade), while in October, after a transitional increase (15), it falls back essentially (4 each for the second and third decades). We had only one observation for November, on the unusually warm autumn of 1963 in the southern part of the Great Plains (Tompa, 16 November, 1 çf). The abrupt increase of the individual numbers speaks for the fact that the immigrated specimens breed on in Hungary during the summer months (HOFFMANN ; & KLOS, 1913). The emergence of the first specimens, developed in Hungary, may j be placed in the first half of July —at least I found the first whole exemplars, also with uninjured cilia, beginning with this time in the light trap materials. The I nummber of summer specimens developed within our borders is assumably much higher than that of the earlier immigrants. It is not an easy task to establish the number of generations evolving in
