Distribution of six little known plant species from Arunachal Pradesh, India

Abstract

Arunachal Pradesh being a part of the Himalaya-East Himalaya biogeographic zone (Rodgers et al. 2000) is also the confluence point of three biogeographic realms, namely, the Afro-tropical, the Indo-Malayan and the Indo-Chinese (Takhtajan 1969). It harbours a unique composition of different plant communities, influenced by various factors including rainfall, temperature, humidity and altitude (Biswas 1966). The biodiversity of Arunachal Pradesh is supported by a wide range of endemic species and various fragile ecosystems. More than 82% of the geographical area of the state is covered with forests, which are the custodians of c. 29% flowering plants of India (Hajra & Mudgal 1997). During the recent floristic survey conducted in the Kurung Kumey District of Arunachal Pradesh, six interesting species were collected which were known only from the type locality. The present collection of these species from areas other than the type localities confirms that they may have a wider distribution in this region. Out of the six species, Dalbergia thomsonii