This plant has bright pink blooms and is a select form of Begonia aff menduminae is purple with silvery white markings.  In the paper ‘Synopsis of Begonia from the Northern Arm of Sulawesi and Sangihi Island, Indonesia, including three new species by Wisnu Ardi and D.C. Thomas, this plant most resembles the plant in photo C (p. 31/fig 10).  

“Based on observations in the field, Begonia mendumiae is morphologically highly variable, particularly regarding the indumentum density, leaf size and coloration, and ovary shape both among individuals in populations and among different populations. However, most generative characters are more stable, allowing clear identification of the species. Individuals from the Poso Pesisir Utara population have larger leaves, up to 21 × 14 cm, whereas distinctly smaller leaves (c.15 × 10cm) are found in the other populations. Most of the populations show several variable characters such as adaxial leaf lamina colour, which can be reddish-dark green with irregular silvery variegation or light green without any variegation; short (up to 5 mm long) or long (up to 50 mm long) female inflorescence peduncles; 1- or 2-flowered female inflorescences; ovate or lanceolate female flower tepals; ellipsoid or cylindrical ovaries (without wings); and narrow or wider ovary and fruit wings, which can be rounded or cuneate at the base…[proposed conservation status] Near Threatened (NT). Begonia mendumiae is endemic to Sulawesi and relatively widespread on the island…mostly occurring in disturbed lowland forest or limestone forest habitats. However, its known range does not include any legally protected areas in Sulawesi. Consequently, we assess this species as Near Threatened.”