Abstract
Four curculionid weevil species belonging to the subfamily Brachyrhininae collected in Sault Ste. Marie, Ontario, Canada, were studied cytologically. No males were found in every species here studied. The results are summarized in Table 1.
Table 1. Species of weevils under study and their chromosome numbers established
It was found that Brachyrhinus ovatus, Sciaphilus asperatus, and Trachyphloeus bifoveolatus had 33 chromosomes, while Tropiphorus terricola possessed 44 chromosomes. On the basis of the fact that the basic number of parthenogenetic weevils (Curculionidae) was reported as 11, the former three species is triploid and the latter species is tetraploid. In the light of the present results, it seems to be very probable that four species dealt with in this paper are parthenogenetic in reproduction.
