Rosewood (Aniba rosaeodora Ducke, Lauraceae) is ecologically and economically important to the Amazon region. As a consequence of its economic importance, rosewood populations have been decimated in the Amazon forest. Species of nine genera of the Lauraceae family have characterized karyotypes with n = x = 12 chromosomes in the gametophytic phase but the genus Aniba is one of the least studied Lauraceae genera with a previously undescribed genome. We used cytogenetic techniques to determine that the A. rosaeoddra karyotype contained 12 pairs (2n = 24) of relatively small submetacentric chromosomes with lengths ranging from 1.34 to 2.25 mu m and a nucleolar organizer region (NOR) in the short arm of chromosome 7. Flow cytometry gave 2C = 2.32 pg of DNA, equivalent to approximately 2.24 x 10(9) base pairs.