GEOGRAPHICAL PATTERN IN AUTOGENY AND WING LENGTH IN AEDES TOGOI (DIPTERA: OJLICIDAE)

Autogeny and wing length variation in Aedes togoi (Theobald) studied for 68 Japanese populations from localities ranging from 45 N (subarctic) to 26 N (sub- tropical) together with Taiwan, two Malaysian and Canadian population reared at 25C and photoperiod of 12:12 h (L:D). Wing length shortened with decreasing latitude gradually in the subarctic and temperate populations but distinctly in the subtropical populations, and the tropical populations had conspicuously short wings. All nearly all females of both subarctic and tropical populations in Asia produced approximately 70-110 eggs without blood meals. In temperate and subtropical populations, autogeny rates varied from to 50% with fewer eggs. Thus, the geographical pattern in autogeny rate and autogenous egg number showed "U"-shaped pattern where the less autogenous, medium- sized populations intervened between the highly autogenous, large-sized subarctic popula- tions and the highly autogenous, small-sized tropical populations. The Canadian population fell within the range of temperate subtropical Japanese populations with respect to wing length and autogeny rate.