Chalcosoma atlas: 20,neoXY (Fig. 3 B)

Published data: Dutrillaux & Dutrillaux (2012).This karyotype is fairly unusual, because the formation of its large and bi-armed neo sex-chromosomes, probably by a double translocation with autosomes, is not accompanied by a reduced number of autosomes. The size of the large chromosomes (nos 1-3) is roughly similar, instead decreasing in size, which suggests that fragments of the two largest of them contributed to form the neoXY by translocation. Heterochromatin is fairly abundant at all centromeric regions.All chromosomes are meta-/sub-metacentric. NOR location: large autosome (no. 3).