Evidence of Sympatric Speciation in Cyathea sinuata Hook. & Grev. from Lowland Rainforests of Sri Lanka

Research on Cyathea sinuata, a unique tree fern endemic to Sri Lanka, reveals evidence of sympatric speciation—a process where new species evolve within the same geographic area. Cluster analysis of 23 individuals identified two distinct subgroups within C. sinuata: one with typical characteristics and another exhibiting morphological differences such as dentate leaf margins, irregular crown shapes, and variations in veinlets and spore arrangement. These findings suggest that Subgroup II may represent an early stage of speciation, potentially a new morphotype or species. The study highlights the significance of Sri Lanka's ecological isolation, which fosters diverse fern morphology. Continuous monitoring is recommended to further elucidate this evolutionary process within Sinharaja Forest Reserve and other protected areas.

Ranil, R. H. G., Pushpakumara, D. K. N. G., & Wijesundara, D. S. A. (2014). Evidence of Sympatric Speciation in Cyathea sinuata Hook. & Grev. from Lowland Rainforests of Sri Lanka. Proceedings of International Forestry and Environment Symposium, 18(0). https://doi.org/10.31357/fesympo.v18i0.1881