| Ginkgoopsida Temporal range: | |
|---|---|
| | |
| Ginkgo biloba | |
| Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Gymnospermae |
| Division: | Ginkgophyta |
| Class: | Ginkgoopsida Meyen |
| Proposed orders | |
| |
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]