Plant species first collected 27 years ago identified as new species of the genus Uniyala

Uniyala keralensis
| Photo Credit: Special arrangement

A dense shrub with light purple flowers found in the Agasthyamala Biosphere Reserve in Kerala’s Thiruvananthapuram district has been confirmed as a distinct species of the genus Uniyala. The botanically significant development is also interesting in that a specimen of this plant was first collected by researchers 27 years ago.

Researchers have named the new species, which is endemic to southwest India, Uniyala keralensis (family Asteraceae) after the State of Kerala.

E.S. Santhosh Kumar and S.M. Shareef at the Jawaharlal Nehru Tropical Botanic Garden and Research Institute (JNTBGRI), Palode, had collected a specimen in 1998 on one of their field exploration trips. In the years that followed, more specimens were gathered from different parts of the biosphere reserve which is located towards the southern end of the Western Ghats, a global biodiversity hotspot.

Back then, the shrub was thought to be Vernonia multibracteata. Some years ago, the genus Uniyala was separated from Vernonia and classified as a new genus.

Subsequent studies and comparisons with specimens kept at herbaria proved that the specimen collected from the Agasthyamala biosphere 27 years ago was similar to some of the Uniyala species, but differed from them enough to be designated a distinct species. The findings have now been highlighted in a paper by the two JNTBGRI researchers in the journal Phytotaxa.

Physically, Uniyala keralensis is a “small to large shrub,” growing up to one to three metres in height and sporting attractive light purple florets, according to the paper. Compared to its cousins Uniyala comorinensis and Uniyala salviifolia, Uniyala keralensis has, among other things, larger leaves, fairly long petioles – the slender stalk that joins the leaf to the stem – and fewer lateral veins on the leaves. Flowering and fruiting occurs during August to April.

The authors note that the new species is found in open areas of the western mountain slopes of the Agasthyamala Biosphere Reserve (ABR) at elevations ranging between 700 to 1,400 metres. “The present population consists of nearly 5,000 individuals of various ages in four subpopulations occupying an area of 250 km2. Following the IUCN Red List Criteria (IUCN 2024), Uniyala keralensis is assessed as Data Deficient (DD),” the Phytotaxa paper said.

The genus Uniyala is named after the renowned plant taxonomist B.P. Uniyal. The genus has 11 species in southern India and Sri Lanka.