ABSTRACT
Conifers are classifi ed with seed plants, which include fi ve living groups: conifers, cycads, Ginkgo, gnetophytes and angiosperms. The fi rst four groups comprise the gymnosperms, which expose their ovules during pollination. There is wide acceptance for the rank of order Coniferales (also called Pinales), and conifers have often been recognized at the higher taxonomic ranks of class (Coniferae, Coniferopsida or Pinopsida) and division (Coniferophyta or Pinophyta). Living conifers are grouped in six families, 71 genera (Fig. 1-1), and ca. 670 species. In a recent global checklist (Farjon 2001), 69 genera and 630 species were recognized; we treat Callitropsis and Xanthocyparis as separate from Cupressus and recognize more species in Pinaceae and Cupressaceae.
