Abstract
The two calendrid weevils, Sitophilus granaries and S. oryzae, have the chromosome formulae 11AA+Xyp and 10AA+neo-XY. They therefore differ from related Curculionidae, bisexual species of which, with the exception of Anthonomus scutellatus, conform to the formula 10AA+Xyp or 10AA+XO. Contrary to earlier reports they are nevertheless meiotically orthodox.
Additional species investigated, with their formulae, are as follows: Platystomidae-Euparius marmoreus=10AA+Xyp; Curculionidae-Sitona lepidus, Sitona cylindricollis, and Hylobius congener=10AA+Xyp and Anthonomus scutellatus=13AA+Xyp; and Scolytidae-Hylurgops pinifex, Dendroctonus engelmanni, and Ips pini=14AA+Xyp.
These findings are discussed in relation to the taxonomic disposition of the three families.
