Stamen venation in the Winteraceae

Stamen venation is described for all species of Pseudowintera and an interspecific hybrid; the single species of Exospermum, several species of Belliolum, Drimys, Tasmannia (syn. Drimys sect. Tasmannia) and Zygogynum, as well as one species of Bubbia. One, two and three-veined stamens were found in several taxa, in contrast to previous reports that invariably stamens have a single (median) vein. The presence of isolated, apparently vestigial, lateral veins in many stamens of some taxa, seems evidence there has been an evolutionary reduction from three- to one-veined stamens. In view of the antiquity of the Winteraceae, this lends support to the hypothesis of Bailey and Nast, that three-veined stamens are a primitive feature of the woody Ranales. No obvious correlation was found between stamen morphology and type of pollinator.