Parity diagnosis and ovulation in Culiseta inornata (Diptera:Culicidae).

The hypothesis that ovulation in mosquitoes results in the formation of a single basal dilatation per ovariole, regardless of previous history of the ovariole, was supported for known 1- and 2-parous Culiseta inornata (Williston). The examination of histological sections of whole ovaries of Cs. inornata, before and after ovulation in the 1st gonotrophic cycle, indicated that the pedicel is destroyed during ovulation. Dissections revealed that 88% of 1- dilated ovarioles in 1-pars lacked a pedicel, and 90% of 2-pars had a mean of only 12.5 2-dilated ovarioles (10% had none). Criteria are proposed for the separation of nulliparous, 1-parous and 2-parous (anautogenous) Cs. inornata. Fifty percent of nullipars and 42% of 1-pars had a mean of 2.6 and 2.0 rogue ovarioles, respectively. The criteria account for rogue ovarioles in nullipars, but misdiagnose 2-pars as 1-pars when the former have few (or lack) diagnostic ovarioles. This diagnostic error can be reduced using structural differences in rogue versus diagnostic ovarioles.