The Calycanthaceae (sweetshrub or spicebush family) is a small family of flowering plants included in the order Laurales. The family contains three genera and only 10 species, restricted to warm temperate and tropical regions:
- Calycanthus (2 species; western and southeastern North America)
- Chimonanthus (6 species; eastern Asia)
- Idiospermum (1 species; Queensland, Australia)
- Sinocalycanthus (1 species; eastern Asia) - morphological and molecular data indicate that this is a member of Calycanthus
They are aromatic deciduous shrubs growing to 2–4 m tall, except for Idiospermum, which is a large evergreen tree. The flowers are white to red, with spirally arranged tepals. DNA-based phylogenies indicate that the Northern Hemisphere Calycanthus and Chimonanthus diverged from each other in the mid-Miocene, while the Australian Idiospermum had already diverged by the Upper Cretaceous and likely represents a remnant of a former Gondwanan distribution of Calycanthaceae that included South America, as indicated by the occurrence of Cretaceous Calycanthaceae fossils in Brazil.