New Begonia species found in Kollam's Rosemala evergreen forests

Researchers at the Jawaharlal Nehru Tropical Botanic Garden and Research Institute (JNTBGRI) in Thiruvananthapuram have identified a new species of the genus Begonia from the evergreen forests of Rosemala in Kollam district, within the Western Ghats.

The plant was spotted during an exploration aimed at collecting wild ornamental plants. The team has named the species Begonia rajvikramanii in honour of R. Raj Vikraman, former Head of the Garden Management Division at JNTBGRI, recognising his role in developing the institute's garden and in managing its ex situ plant conservation programmes. JNTBGRI functions under the Kerala State Council for Science, Technology and Environment (KSCSTE).

The finding, detailed in a paper by E.S. Santhosh Kumar, S.M. Shareef, P.P. Anusha and Rejitha Joseph, has been published in the latest issue of Phytotaxa.

According to the paper, the species is so far known only from its type locality at Rosemala. It grows in wet habitats, particularly on rocky cliffs and road-cut walls, at elevations of roughly 200 to 350 metres. Its flowering and fruiting period runs from August to April.

Comparisons with existing literature, type specimens and authenticated herbarium material showed the plant to be morphologically closest to Begonia tenera Dryander, a species found in India and Sri Lanka. It differs from that species in several physical characteristics, which the authors say justifies its recognition as a distinct species.

The known population consists of about 200 mature individuals spread over an area of less than 5 square kilometres. Applying the IUCN Red List Categories and Criteria (2024), the team has assessed Begonia rajvikramanii as 'Data Deficient', pending a fuller assessment.

Begonia is among the largest flowering plant genera, with 2,200 accepted species distributed mainly across tropical and sub-tropical Africa, Asia and America. In the Western Ghats, the genus is represented by 23 species.

The discovery comes as the ghats region draws attention over the Kerala government's recommendations concerning Ecologically Sensitive Areas.