According to POWO and IPNI, only the frist one is accepted :
"Begonia keraudreniae Bosser, Fl. Madagasc. Fam. 144: 59 (1983), as 'keraudrenae' (1983)."
And Padme adds :
"Begonia keraudremae Pinner et al. orth. var."
Both Begonia keraudreniae Bosser and Begonia keraudrenae Bosser are in the backbone as accepted species. The former with one occurrence and the latter with seven. The later appears to be a misspelling of the former and should ideally be registered as a synonym of Begonia keraudreniae Bosser, see the source from the GBIF user.
Begonia keraudremae Pinner et al. is listed as doubtful but the additional information provided by the GBIF user (orth. var.) is not included and the species is not registered as a synonym of Begonia keraudreniae Bosser, which it probably should.
This issue is based on feedback on GBIF helpdesk:
Both Begonia keraudreniae Bosser and Begonia keraudrenae Bosser are in the backbone as accepted species. The former with one occurrence and the latter with seven. The later appears to be a misspelling of the former and should ideally be registered as a synonym of Begonia keraudreniae Bosser, see the source from the GBIF user.
Begonia keraudremae Pinner et al. is listed as doubtful but the additional information provided by the GBIF user (orth. var.) is not included and the species is not registered as a synonym of Begonia keraudreniae Bosser, which it probably should.