An early Chamaecyparis (Cupressaceae) from the Late Cretaceous of Vancouver Island, British Columbia, Canada

Fossil remains of a Chamaecyparis-like member of the Cupressaceae occur in the Upper Cretaceous Comox Formation of Vancouver Island, British Columbia. The cedar bore both flattened, opposite-branching foliage of the Cupressinocladus interruptus type, as well as alternate-branching foliage more similar to that of extant Thuja. Seed cones attached to the foliage are minute, about 3.0 mm in diameter, and consist of four cone scales with abaxial, leaflike umbos. Despite their small size, the structure of the cones and their disposition on axes resembles those of extant species of Chamaecyparis. It is apparent that the Comox cedar is closely related to extant Chamaecyparis and appears to represent an early member of the clade. These data challenge the hypothesis that Chamaecyparis evolved from a Cupressus-like ancestor with large, many-scaled seed cones and terete branches. Key words: Cupressaceae, Chamaecyparis, Late Cretaceous, fossil, seed cones, evolution.