Ginkgoopsida

Ginkgoopsida is a proposed class of gymnosperms defined by Sergei V. Meyen in 1984 to encompass Ginkgoales (which contains the living Ginkgo) alongside a number of extinct seed plant groups, which he considered to be closely related based on similarities of morphology of pollen, seeds, cuticles, short shoots and leaves.^[1][2][3] The validity of this group as a whole has been considered questionable by other authors, who consider that it is unlikely to be monophyletic.^[4] Other authors have used the class as a monotypic grouping, including only Ginkgoales.^[5] Some authors have used the clade Ginkgophyta to encompass both Ginkgoales and Czekanowskiales/Leptostrobales, which are suggested to be closely related groups.^[6]

Ginkgoopsida Temporal range: Carboniferous–Recent PreꞒ Ꞓ O S D C P T J K Pg N
Gingko biloba
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Gymnospermae
Division:	Ginkgophyta
Class:	Ginkgoopsida Meyen
Proposed orders
Ginkgoales †Czekanowskiales †Peltaspermales? †Corystospermales? (Umkomasiales) †Caytoniales? †Dicranophyllales? †Calamopityales? †Callistophytales? †Glossopteridales? †"Palaeophyllales"?