Three new species of Piperaceae from Thailand

Abstract

Three new species of Piperaceae, Piper dominantinervium A. Chaveerach & P. Mokkamul, P. pilobracteatum A. Chaveerach & R. Sudmoon from southern Thailand, and P. phuwuaense A. Chaveerach & T. Tanee from northeastern Thailand, are described and illustrated. P. phuwuaense is considered rare and endemic to Phu Wua Wildlife Sanctuary. Morphological differences between the new species and related taxa are discussed. Key words Piper, Piper dominantinervium A. Chaveerach & P. Mokkamul, Piper phuwuaense A. Chaveerach & T. Tanee, Piper pilobracteatum A. Chaveerach & R. Sudmoon, Piperaceae, new species, Thailand. The genus Piper L. is estimated to contain over 1000 species which are distributed mainly in tropical regions of the world. Several species have great economic and cultural importance and are used as foods, medicines, stimulants, antiseptics and antioxidants. Moreover, their essential oil and leaf extracts possess activities against several bacterium strains and fungi. Leaves of P. hispidinervum C. DC. contain a high level of safrole (83%-93%) which is an important raw material for chemical industries. Two derivatives of safrole are heliotropin, which is widely used as a fragrance and flavoring agent, and piperonyl butoxide, which is a vital ingredient of pyretroid insecticides. There are other Piper species with possibilities for extracting safrole and can be cultivated in the local communities. Because of the usefulness of many known Piper species, this diverse plant group should be studied in more depth to determine more economic and medicinal uses of other species. We have been concentrating our work on species diversity of this genus in Thailand. Many species have been reported recently (Chaveerach & Picheansoonthon, 2004) and some of these species descriptions are in the process of publication. It is evident that the plant diversity and taxonomy in Thailand have not been completed.