Floral aspects of Barclaya (Nymphaeaceae): pollination, ontogeny and structure

Abstract

Barclaya, endemic to Southeast Asia, includes four species: B.longifolia WALLICH. B. motleyi HOOKER f., B. kunstleri (KING) RIDLEY,and B. rotundifolia HOTTA. The genus has been traditionally assignedmonotypic status in the family Barclayaceae or tribe Barclayeaeprimarily based on the occurrence of a hypogynous calyx, originallyinterpreted as an involucre in an otherwise epigynous flower,orthotropous ovules, lack of an aril, and inaperturate pollen. Cladisticand molecular studies support the association of Barclaya with Euryale,Victoria, Nymphaea, Ondinea, and Nuphar in the family Nymphaeaceae.Floral structure reveals (1) vasculature and developmental support forthe hypothesis that the hypogynous appendages are sepals, (2) thatpollen is zonasulculate, (3) that floral ontogeny is similar to thatpreviously described for epigynous members of the Nymphaeaceae s. str.,and (4) anatomical and morphological similarities with otherNymphaeaceae s. str. The cleistogamous and chasmogamous flowers areself-pollinating, the latter perhaps facilitated by flies in emergentflowers.