Taxonomic update of begonia species in Samar Island

Abstract

Samar Island, the country’s third largest island, contains pristine forests suitable for Begonia species. Despite that, Samar remains underexplored, with a record of only two Begonia species - B. samarensis Merr. and B. quercifolia A. DC. both belonging to Begonia section Petermannia. Begonia species are usually perennial succulent herbs, rarely subshrubs. Asymmetric leaves are the most distinct characters of Begonia. In the study, type localities were revisited to collect herbarium specimens and update the taxonomic record of the species. It includes morphological characterization only. After securing the necessary permits, the researchers conducted a study of Begonia species of the Samar Island Natural Park (SINP). Seven species were found in the municipality of Paranas, one species in the municipality of Basey, and one in the city of Calbayog. After thorough studies of living and herbarium specimens, four new species proposed to be named as B. sinp, B. tenani, B. sohotonensis and B. tarangbanensis are reported. Records of B. samarensis and B. pseudolateralis Warb. are hereby documented, while the identification of the other species cannot be ascertained due to incomplete reproductive parts. For further studies, the researchers recommend a botanical exploration in other places in Samar Island, especially because many forests, caves and waterfalls in Samar remain undisturbed and unexplored.