Typhonium jinpingense, a New Species from Yunnan, China, with the Lowest Diploid Chromosome Number in Araceae

Fieldwork was conducted in the southeast part of Yunnan Province, China, in October 1999. The new species was found on a slope near a small stream with an elevation from 1000 to 1550 m in Jinping County, Yunnan Province, China. This plant was first collected and identified as Typhonium blumei Nicolson & Sivadasan, as the leaves were quite similar to this species. The plants were subsequently grown and propagated; so far, more than 20 individuals are cultivated in the Kunming Botanical Garden. From April to August 2000 four of them flowered, displaying quite different characteristics from T. blumei. After checking the chromosome number for several individuals, we found the lowest diploid chromosome number in Araceae reported to date. We checked the morphological characteristics carefully and compared them to all the species in the genus Typhonium, and realized this taxon is an undescribed species. According to the revision of Typhonium (Sriboonma et al., 1994) and our recent investigations, 16 species and 4 varieties in the genus have been found in China thus far, belonging to 5 sections. Recently, Hetterscheid and Boyce (2000) merged the genus Sauromatum Schott (all 3 species found in China) with Typhonium Schott (Wang & Li, 1999). Thus the number of Typhonium species in China is now thought to be 19. However, based on species richness in neighboring countries (Hetterscheid et al., 2001; Hetterscheid & Nguyen, 2001), this is likely to be an underestimate of the actual number of Typhonium species in China, especially in the southern part of Yunnan Province.