Karyomorphology of Eusideroxylon zwageri (Lauraceae)

Abstract

The chromosome number and morphology of Eusideroxylon zwageri, the only species of the genus, was investigated for the first time. Results showed that, although Eusideroxylon is similar to other Lauraceae in karyotype at metaphase as well as in chromosome features at interphase and prophase, the genus is distinct in the family (with x=12) in having 2n=30. Its unique chromosome number, along with its several distinctive floral features such as tepaloid outer staminodial whorls and semi-inferior ovary, suggests that Eusideroxylon is one of the most derived genera in the family.