A New Pollen Aperture in Schleichera oleosa (Lour.) Oken from Madhya Pradesh, Central India, and its Taxonomic and Evolutionary Significance

Abstract

Angiosperms demonstrate a surprisingly frequent phenomenon of variability in the gross pollen morphological characteristics. In the
present study, we recorded and described a new aperture in the pollen grains of Schleichera oleosa (Lour.) Oken, a monotypic genus
of the soapberry family Sapindaceae, from Madhya Pradesh, central India, based on the LM and CLSM observations. This condition is
termed the tetra-zono-parasyncolporoidate condition. A new pollen aperture has been recorded in this monotypic genus with the
usual one (tri-zono-parasyncolporoidate condition), and this phenomenon of the occurrence of a new with increased number of pollen
aperture is known as pollen aperture heteromorphism. The study will further help identify this taxon from the sedimentary archives as
one of the indicators of the warm and humid (moist) climate and increased monsoonal rainfall.