Polycarpelly in Idiospermum australiense (Calycanthaceae)

Abstract

Idiospermum australiense (Diels) S.T. Blake (Calycanthaceae) is restricted to two relatively small regions in the lowland tropical rainforests of north-east Queensland, Australia. Previous morphological studies have focused on specimens from the northernmost of these two regions. Examination of flowers from all known populations of the species revealed significant differences between the northern and southern regions with respect to numbers of floral parts, especially carpels. Polycarpelly was found to be widespread in the southern populations, a feature previously unreported in the literature.