Osbeckia zubeengargiana

Osbeckia zubeengargiana, locally known as mon jai, is a species of flowering plant in the family Melastomataceae discovered in the grassland ecosystems of Manas National Park in the Indian state of Assam. The species was formally described in 2026 by botanists Barnali Das, Prashob Pulpra, and Namita Nath following taxonomic research on the genus Osbeckia in Northeast India.^[1]

The species was named in honour of Assamese singer and cultural figure Zubeen Garg in recognition of his contributions to Assamese culture and advocacy for environmental conservation.^[2]

The discovery highlights the botanical diversity of Northeast India, part of the Eastern Himalaya biodiversity hotspot.^[3]

The species was discovered during botanical field surveys conducted between 2021 and 2025 as part of doctoral research on the family Melastomataceae in Assam.^[2] Researchers collected specimens from grassland habitats in Manas National Park in Baksa district, where a significant population of the plant was observed.^[2]

After morphological comparisons with known taxa and examination of herbarium specimens, the researchers determined that the plant represented a previously undescribed species.^[1] The species was formally described in 2026 by researchers Barnali Das and Namita Nath of Gauhati University and Prashob Pulpra of N. S. S. College, Manjeri following taxonomic research on the genus Osbeckia in Northeast India.

Osbeckia zubeengargiana belongs to the genus Osbeckia, a group of flowering plants distributed across South and Southeast Asia.^[4]

The genus is particularly diverse in the Eastern Himalaya and the Western Ghats.^[3] The new species was described based on morphological examination of field collections and herbarium specimens deposited at the Gauhati University Herbarium.^[1]

Osbeckia zubeengargiana is a perennial erect shrub that can reach approximately 3–3.5 metres in height.^[2]

Key morphological characteristics include:

• Tetramerous pink flowers with four petals
• Eight stamens with S-shaped anthers
• Linear-lanceolate leaves with distinctive venation
• Urceolate capsule fruits containing numerous curved seeds

The ovary is fused to the hypanthium for approximately two-thirds of its length and bears bristle-like hairs at the crown.^[1]

The species is most closely related to Osbeckia rostrata due to its tetramerous floral structure.^[1]

However, it differs in several diagnostic characteristics, including:

• Growth habit and branching pattern
• Leaf morphology and bract structure
• Hypanthium morphology
• Style base characteristics
• Seed size and shape

These differences supported its classification as a distinct species.^[1]

The species is currently known only from the grasslands of Manas National Park in Assam.^[2][5]

The plant grows in association with several grassland species, including:

• Chrysopogon zizanioides
• Maesa indica
• Bombax ceiba
• Dillenia pentagyna

These plant communities are characteristic of the alluvial grassland ecosystems of the Brahmaputra valley.^[1]

The species inhabits open grassland ecosystems and appears to be adapted to seasonal flooding and monsoon climatic conditions typical of the Brahmaputra basin.^[1]

Flowering and fruiting occur between mid-September and January.^[1][6]

The species is currently known only from its type locality in Manas National Park. Due to limited distribution data, researchers have suggested a preliminary status of Data Deficient under IUCN Red List guidelines pending further field surveys.^[1]

The genus Osbeckia was first described by Carl Linnaeus in the 18th century and includes more than forty species distributed across tropical Asia.^[7] Several species of the genus have been described from India in recent decades as botanical exploration in biodiversity hotspots continues to reveal new taxa.^[8]

• Manas National Park
• Melastomataceae
• Zubeen Garg