Eye colour of
Triatoma infestans
is controlled at a single autosomal locus, with black-eye as the dominant
gene and red-eye as the recessive. Inheritance of these characters follows
a classical Mendelian system, enabling eye colour to be used as a marker
for studies of mating frequency. We found no significant differences in
oviposition rates and egg hatching rates irrespective of parental phenotypes.
Different mating schedules between red-eye and black-eye parents showed
that eye colour did not affect mating competence. Females mated with a single
male or with different males together or in succession produced similar
numbers of fertile eggs, with the eye colour of the offspring reflecting
exposure to the different males. We conclude that although a single mating
can provide sufficient sperm for the whole reproductive life of the female,
multiple matings can result in balanced assortative sperm usage from the
spermatheca.