Plant Diversity ›› 2003, Vol. 25 ›› Issue (04): 1-3.

• Articles •    

Mesozoic Ginkgoaleans: Phylogeny, Classification and Evolutionary Trends

ZHOU Zhi-Yan   

  1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China
  • Online:2003-08-25 Published:2003-08-25

Abstract: In this article, the recent progress made in studies of Mesozoic ginkgoaleans, especially those of the Chinese material, is summarized with a brief review of the origin and distribution of ginkgoaleans in the geological history. For a long time, our knowledge of ginkgoaleans has been obtained mainly from fos-sil leaves that are of little taxonomic and phylogenetic significance. The proposed classification was based on phylogenetic analyses of well-preserved taxa of which not only vegetative organs, but ovulate organs were known. It is supplemented here with the defining features, and geological and geographical distribu-tion of the extinct families. Trie taxonomic positions of taxa for vegetative organs are left undetermined un-less they are found related to reproductive organs. Tlie general evolutionary trends of ginkgoaleans since Permian was reduction of both vegetative and reproductive organs in spite of being greatly diversified in morphology in the Jurassic and Early Cretaceous time.

Key words: Mesozoic