The Calycanthaceae family consists of fragrant, deciduous shrubs reaching 2-4 meters in height, with the exception of Idiospermum , which grows into a large evergreen tree. It comprises 3 genera and 10 species, and its distribution is limited to warm temperate and tropical regions. These include: Calycanthus (3 species; 1 species in western and southeastern North America and eastern Asia); Chimonanthus (6 species; East Asia); and Idiospermum (1 species; Queensland, Australia). The flowers range in color from white to red, with petals arranged spirally. Based on DNA phylogenetic trees, Calycanthus and Chimonanthus in the Northern Hemisphere diverged in the Middle Miocene, but Idiospermum in Australia had already diverged by the Upper Cretaceous. The discovery of Cretaceous Calycanthaceae fossils in Brazil suggests a likely remnant of a former Gondwanan distribution that included South America.
This article provides a comprehensive, field guide-style introduction to plants belonging to the Calycanthaceae family.
The basic information is based on Hayashi (2014). Photos are replaced as better ones become available. Also, while the identification is done by the author, please note that it may be changed without notice if there are any misidentifications.
No. 0136 Chimonanthus praecox
Deciduous shrub. Leaves are 8-20 cm long, with the widest part near the base to the middle. Petioles are 3-8 mm long. The leaves are large and long ovate, with a rough surface. It is easy to identify because there are few trees with large, entire leaves growing opposite each other. The sac-like fruits, about 4 cm long, that remain on the branches for a long time are also a good indicator. The flowers are yellow and bloom from December to February. The tree grows to a height of 2-5 m. Native to China. Commonly used as a garden tree and park tree.






No.0136.1 Chimonanthus praecox f. concolor
This is a variety of winter sweet (Chimonanthus praecox) with yellow inner petals. It has become widely planted in recent years.





References
Hayashi, Masayuki. 2014. 1100 Tree Leaves Identified Through Real-Life Scans. Yama-kei Publishers, Tokyo. 759pp. ISBN : 9784635070324

