Cathaya is a genus in the pine family, Pinaceae, with one known living species, Cathaya argyrophylla.^[1] Cathaya is a member of the subfamily Laricoideae, most closely related to Pseudotsuga and Larix. A second species, C. nanchuanensis, is now treated as a synonym,^[2] as it does not differ from C. argyrophylla in any characters.

Cathaya is confined to a limited area in southern China, in the provinces of Guangxi, Guizhou, Hunan and southeast Sichuan. It is found on steep, narrow mountain slopes at 950–1800 m altitude, on limestone soils. A larger population has been reduced by over-cutting before its scientific discovery and protection in 1950.

The leaves are needle-like, 2.5–5 cm long, have ciliate (hairy) margins when young, and grow around the stems in a spiral pattern. The cones are 3–5 cm long, with about 15–20 scales, each scale bearing two winged seeds.

One or two botanists, unhappy with the idea of a new genus in such a familiar family, tried to shoehorn it into other existing genera, as Pseudotsuga argyrophylla and Tsuga argyrophylla.^[3] It is however very distinct from both of these genera, and these combinations are not now used.

The Butchart Gardens in Victoria, British Columbia had a small living specimen. The tree died in 2017.

Fossil record

Cathaya sp. fossils are described from the early Pleistocene of southern Portugal.^[4] They are abundant in European brown coal deposits dating from between 10–30 million years ago.

References