The only Asian sections with berries (fleshy fruits that do not dehisce) are sect. Sphenanthera and sect. Leprosae, which differ primarily in fruit shape – turbinate in sect. Sphenanthera and narrowly cylindric in sect. Leprosae. This new species, Begonia bataiensis Kiew, with its cylindric, fleshy, indehiscent fruit therefore falls within sect. Leprosae.
Section Leprosae accommodates, besides this new species, three others, Begonia leprosa Hance, B. longicarpa K.Y.Guan & D.K.Tian and B. cylindrica D.R.Liang & X.X.Chen (Shui et al., 2002). Apart from B. longicarpa, which has been collected from the Lao Cai Province, in the extreme north of Vietnam, just across the border from China, the other two are confined to southern China. This new species therefore extends the distribution of this section much further south to Kien Giang Province in southwest Vietnam.
Distribution: Endemic to Ba Tai Hill, 3 km NNW of Hon Chong, Kien Giang Province, SW Vietnam.
Habitat: Rooting in soil pockets in clefts in limestone rock, well shaded, at c. 50 m altitude.
Khoe La karst hill (photo: NGUYEN Tran Vy)
Begonia bataiensis live on soil pockets
This species is named for the limestone hill from which it was collected. It was observed on only two other, Bai Voi and Khoe La Hills. All are scheduled for quarrying. Begonia bataiensis is therefore highly endangered, because its narrow distribution and small population size make it vulnerable to extinction.
Truong Quang Tam
Center for Biodiversity and Development
Ruth Kiew & J.J. Vermeulen
The Singapore Botanic Gardens
Gardens’ bulletin Singapore 57 (2005) 19-23