A new species of Begonia and rediscovery of B.loheri(section Petermannia, Begoniaceae) from Luzon Island, Philippines

A new species,Begonia subaequifolia Y.P.Ang & J.Collantes, is here described and illustrated from Luzon Island, Philippines. It closely resembles Begonia jagori Warb. by having an upright habit, stems covered with short brown hairs, short petioles, and an ellipticlamina with an oblique and shallowly cordate base. However,Begonia subaequifolia is distinct by having smaller stipules, sub-symmetrically oblong-ovate to narrowly elliptic-ovate lamina with pinnate venation, a crenate or serrulate leaf margin, the staminate inflorescence in a dichasial cyme, and smaller tepals in staminate flowers. We also report the rediscovery of B.loheri Merr., a poorly known Philippine endemic Begonia species, and provide an amended description, lectotypification, and photographs.