A synopsis and a new species of the E Asian genus Pinellia (Araceae)

Pinellia Ten. is a small genus in the family Araceae, which contains 105 genera worldwide (Li 1986, Mayo & al. 1997). The genus is recognized by the present authors as having nine species, distributed in mainland China, Korea and Japan, with two species regionally naturalised in Europa, North America and Australia.
The genus Pinellia was established in honour of Giovanni V. Pinelli (1535-1601) by M. Tenore in 1839 based on P. tuberifera Ten., which is a superfluous name since Arum subulatum Desf. was cited as a synonym in the protologue. That latter name is a taxonomic synonym of Arum ternatum Thunb., which is the first known species now recognised as a member of Pinellia, namely P. ternata (Thunb.) Breitenb., and which was described by Thunberg (1784) from a plant collected in Japan between Iedo and Nagasaki.
Pinellia is characterized by (1) the female zone of the spadix being adnate to the spathe, (2) the male and female zones of the spadix with naked flowers being separated by a sterile zone, (3) the presence of an appendix of the spadix and (4) the presence of a septum at the constriction of the spathe (except in P. pedatisecta where a constriction and septum is absent). Engler (1920) placed Pinellia in the subfamily Aroideae, a placement that has since been accepted. According to a recent chloroplast DNA phylogeny (Renner & al. 2004), Pinellia is closely related to Arisaema and Typhonium.
A few species of the genus, in particular Pinellia ternata, are used in Chinese herbal medicine (see, e.g., Hu 1977, 1989, Huang & al. 1986, He & al. 2005), P. ternata and P. tripartita are also popular for ornamental use.

We present the first synopsis of the entire genus since Engler (1920) and it updates previous taxonomic contributions on the Chinese species (Li & al. 1977, Wu & Li 1979, Li 1995, Li & al. 1997a).