The chromosomes of the Japanese weevil, Catapionus gracilicornis Roelofs have been investigated in Aomori Prefecture. Both hexaploid (6x=63) and decaploid (10x=100) parthenogenetic races were found in Temma. The species is now known to have six parthenogenetic races, 2x, 3x, 4x, 5x, 6x, and 10x, as well as a diploid bisexual race. It was shown that pentaploid forms arose from hexaploid forms as I stated in 1980.
The Genetics Society of Japan