Taxonomy and diversity of the genus Glossopteris

Abstract

The speciation of Glossopteris leaves in Permian Gondwana of India is re-examined. It is based on study of thousands of specimens collected from Barakar Formation of Karanpura and Bokaro Group of Coalfields. The study of specimens of modern plants showing variation in shape and size of leaves within same species (sometimes within same plant) and survey of published literature, the author was fascinated to express the ideas about the parameters which may be helpful in speciation of the genus Glossopteris. Here. morphological characters have been critically analysed in order to find a reasonable basis for precise specific delimitations. The morphological circumscriptions have been further verified by characters of cuticle which have been taken as associated or supportive characters only. The size and shape of leaves have given secondary importance. The Diversity and the total number of species found in time and space have been tabulated.