Format: ORAL

Resmi Sekarathil1, 2, Nico Cellinese3,K. Karthigeyan2 Santhosh Nampy1,

1 Department of Botany, University of Calicut, Kerala, India 2 Botanical Survey of India, Southern Regional Centre, Tamil Nadu, India 3 Florida Museum of Natural History, University of Florida, Florida, USA

Sonerila Roxb., a taxonomically complex genus in the family Melastomataceae, comprises approximately 180 taxa, and as one of the largest groups in Asia, it is distributed mainly across Sri Lanka, India, Nepal, Bhutan, South China, Taiwan, Indo-China and the Malay Archipelago. The genus is represented by caulescent and acaulescent herbaceous plants of shady habitats. It is easily recognized by its generally trimerous flowers, mostly uniparous (scorpioid) cymes, and 3-locular, inferior ovary. Sonerila is the largest genus in the tribe Sonerileae in India, with 49 species and one variety, including a substantial percentage of endemics. The Western Ghats region indeed stands out as a hotspot for Sonerila with 43 species and one variety, an astonishing 86% of which are exclusive to this particular biogeographic zone. This remarkable richness of species serves as a clear indication of adaptive radiation and explosive evolution within the genus making it an intriguing subject of study in the realm of Melastomataceae systematics and evolution. The present study highlights the diversity of Sonerila in India with a revisionary account including key for the identification, detailed descriptions, notes on infraspecific variations, geographical distribution and conservation status assessment. Six species were found new to science. Nomenclatural issues relevant to the taxonomic study were also resolved, resulting in subsequent synonymy, reinstatement of names, and typifications.