Intraspecific diversity in the Elaeocarpus montanus thwaites (Elaeocarpaceae) species complex in Sri Lanka: Insights from an integrative morphological and molecular approach

Documenting both morphological and genetic diversity in plant populations is a vital component of taxonomic research and plays a key role in biodiversity conservation. While many studies culminate in the recognition of new species or infraspecific taxa, instances where observed variation does not justify formal taxonomic recognition are often underreported. This study presents evidence of intraspecific diversity in Elaeocarpus montanus (Elaeocarpaceae), an endemic species in Sri Lanka, based on field observations that initially suggested a species complex. The study focuses on an integrative approach combining morphometric analysis and molecular phylogenetics. Morphometric results supported the existence of two distinct morphogroups; however, molecular data did not corroborate this division. The morphological variation corresponded to three geographically and attitudinally distinct populations; low, mid, and high elevations in the central mountains. In addition to reporting these findings, we provide an updated morphological description and distribution records with taxonomic clarification. These data contribute significantly to the future taxonomic studies and the conservation of this endemic species.