The glossopterid group of plants in an evolutionary perspective

Abstract

The glossopterid group of plants was the most dominant constituent of the Permian vegetation of the Gondwana Supercontinent. During last one hundred and fifty odd years, a staggering amount of data has accrued on leaves, wood, root, fructifications, seed and pollen that possibly belonged to this group. Evolutionary pathways with the group, however, are yet little understood.

Considering the venation and epidermal features of the leaves, two patterns are unfolded; one with leaves having dichotomizing, almost parallel veins and stomata in linear rows, the other with dichotomising and anastomosing veins and stomata irregularly distributed in the mesh areas.

Oldest glossopterid fructifications, viz., Arberia/Dolianitia show a certain resemblance with the cordaitalean fructifications, thus suggesting that group of plants with Cordaites/Noeggerathiopsis/Pantophyllum type leaf and Arberia/Dolianitia type infructescence probably was the precursor of the glossopterids. Overall evidence suggests the development of this group of plants along two successive lineages.