Begonia subvillosa, new running wild Begonia in Cibodas Botanical Gardens and naturalized prediction

Begonia (Begoniaceae) have been widely cultivated as ornamental plants especially species of begonias introduced from abroad. Two introduced Begonia species, namely B. hirtella and B. cuculata have long been naturalized in Indonesia and one introduced Begonia species was found released from the cultivated area, namely B. subvillosa. Because of morphological information and distribution of B. subvillosa populations in Indonesia are still limited, this study aimed to characterize the morphology, distribution, and stomata type of B. subvillosa in Cibodas Botanical Garden (CBG) and compare them with two previously naturalized Begonia species. The morphological data were described based on living plants found in CBG and added from herbarium specimens and/or protologue of B. subvillosa. The distribution and habitat data of three species were traced using roaming method in CBG area. The stomata preparations were polished using nail polish, then the type of stomata was observed. The SLA and leaf size were measured using ImageJ. Three populations of B. subvillosa have been found in the CBG as the first record of the species outside its natural habitat. Morphologically, B. subvillosa is easily distinguished by the character of the leaf blade and petiole which are covered by brown and dense trichomes. Begonia subvillosa also has the clustering stomata similar to two naturalized Begonias. In addition to morphological adaptation and functional traits, good generative regeneration ability can be increases the chance of naturalization in the future.