Cephalotaxaceae is a small family of conifers. According to recent phylogenetic analyses, it is a monophyletic family including only the single genus Cephalotaxus, while it was previously considered to include Torreya and Amentotaxus in the family. Cephalotaxaceae is closely allied to the yew family Taxaceae, and is often included in a wide interpretation of Taxaceae, based on phylogenetic evidence and close morphological similarities between them. Included species were restricted to east Asia, except for two species of Torreya found in the southwest and southeast of the United States; fossil evidence shows a much wider prehistorical Northern Hemisphere distribution. The most notable differences between Taxaceae and Cephalotaxaceae in its broad sense concerned the cone aril, which fully encloses the seeds of Cephalotaxaceae, the longer maturation of Cephalotaxaceae seeds, and the larger size of the mature seeds.