Temperature effects on the gonotrophic cycle of Culicoides variipennis (Diptera: Ceratopogonidae).

The duration of oogenesis and time to oviposition after blood feeding was studied in Culicoides variipennis held at constant laboratory temperatures. As assessed by daily dissection of ovaries, the time required for greater than or equal to 80% of females to complete egg development at 13, 17, 21, 27, 30 and 34 degrees C was 10, 5, 4, 3, 2 and 2 days, respectively. Mean times to oviposition at these temperatures were 13.8, 8.2, 4.9, 3.6, 3.0, and 2.6 days, while modal values were 13, 6, 4, 3, 3 and 3 days, respectively. Allowing 7 days after onset of oviposition in groups of 100-150 females, cumulative eggs laid/live female were 4.4, 62.6, 68.9, 63.5, 66.5 and 62.4, respectively. These data should prove helpful in estimating the duration of the gonotrophic cycle and deriving daily survivorship estimates from seasonal parity studies in the field.