A chromatic mutation, dark body (mutants with a darker body than wild individuals), allowed us to test the effectiveness of the second mating in the bisexual species Trichogramma turkestanica Meyer, and of the first mating in the thelytokous species T. cordubensis Vargas and Cabello. Second mating in T. turkestanica was mostly efficient (i.e. followed by fertilization). Nevertheless, the latency before the second mating was longer as the time between second and first matings increased. The utilization of the spermatozoa from the second mating increased as the stock of spermatozoa from the first mating decreased. A long time in the presence of a male was necessary to obtain mating of the thelytokous females of T. cordubensis. Such fertilized females produced a low percentage (28%) of daughters from bisexual reproduction.