Plant traits attributable to endemism in persimmons (Ebenaceae: Diospyros spp.) throughout Asia analyzed using phenotypic approaches

Diospyros L. (Ebenaceae) is an indigenous plant group consisting of persimmons and ebony, which play essential ecological roles in tropical and subtropical vegetation communities. Understanding endemism attributes will significantly contribute to biological perspectives and recommendations for species conservation. The purpose of this study is to identify the morphological traits of Diospyros attributable to endemism that indicate low competition, constraints of reproduction and dispersion, and specific adaptation to the environment. To do so, we performed trait filtering based on apomorphic principles. We identified 12 endemism attributes that were obtained from synapomorphic analysis of phenetic clusters, trait filtering of island endemism, and trait filtering of endemism categories. Based on the phenetic cluster analysis, six traits are attributed to endemism, namely, sericeous twigs, the absence of bark lenticels, leaf width 2–5 cm, fruit length and diameter 5–7 cm, seed width 1.5–2 cm, and hard-textured fruits. Trait filtering of island endemism strongly indicated that subcordate leaf tips were related to the endemism to Java and the Lesser Sunda Islands. Five plant traits obtained from trait filtering of island endemism are sericeous fruit and calyx trichomes (Java and the Lesser Sunda Islands), odorless fruits (Sulawesi), nonfleshy fruits (Bornean), and flat fruit calyces (Moluccan). Of the endemism categories, we obtained a leaf width of 2–5 cm as the attributable trait. Vegetative traits inherent to endemism indicated the specific adaptation to particular environments, while reproductive traits indicated seed dispersal limitations. Conclusively, species descriptions that were analyzed using phenotypic approaches provided important information on the endemism-related aspects of the Diospyros genus.