Dendrobium Swartz (1799: 82) comprises approximately 1500 species and is one of the largest genera of Orchidaceae. There are about 80 species in China, of which 14 species are endemic. During a field trip to Zhenyuan County, SW Yunnan, in 2006, LI Jianwu and his colleagues of Xishuangbanna Tropical Botanical Garden (XTBG) found a small, caepsitose species of Dendrobium, which was also collected during another trip to Lincang County in 2010. They found evidence to prove it as a new species of Dendrobium. They described and illustrated the new species, Dendrobium zhenyuanense.

Dendrobium zhenyuanense is similar to D. mucronatum in having small and green flowers, lateral sepals with keel continuing into the mucro and an entire lip with two lamellae), but it differs from the latter by having inflorescences not exceeding leaves, a lip deflexed at one third it length, the lamellae semi-circular and not extending to the apex and an acute lip without callus in front of the lamellae. Dendrobium zhenyuanense is readily distinguished from other species of Dendrobium in China by its small stature, green flowers, mucronate lateral sepal and lip with two separate lamellae.

Only two populations were discovered in the wild. The habitat has been destroyed due to local agriculture. Therefore, the researchers considered the species as critically endangered (CR) under criterion D according to IUCN categories and criteria (IUCN 2010).

The study entitled “Dendrobium zhenyuanense (Orchidaceae), a new Chinese species in section Stachyobium” has been published in Phytotaxa.

Habitat of Dendrobium zhenyuanense

Dendrobium zhenyuanense (Images by LI Jianwu)