Cycadatae - Cycads
Ginkgoatae - Ginkgo
Gnetatae -(This group has no common
name)
Pinatae - Conifers
Gymnosperm- From the Greek gymnos meaning naked and sperma meaning seed.
From the fossil record, the first know gymnosperms occurred about 350 million years ago during the Devonian period. Gymnosperms differ from angiosperms in that there are no true "flowers" present during the reproduction period; pollen and seeds are produced in male and female cones, respectively. Secondly, immature seeds are borne naked or exposed on the scale of the female cone at the time of pollination, and mature seeds are not contained in fruits like berries or apples.
Gymnosperms are divided into 4 classes:
Cycadatae - Cycads
Ginkgoatae - Ginkgo
Gnetatae -(This group has no common
name)