An improvement of the protocol for haploid induction through anther culture of Citrus clementina Hort. ex Tan. cv. Nules was achieved following the evaluation of a number of the factors affecting androgenesis. The influence of thidiazuron (TDZ) and three temperature pre-treatments (4 degrees C, 25 degrees C, 32 degrees C) on the floral buds with respect to anther culture of C. clementina Hort. ex Tan., cv. Nules was investigated. An increased embryoid production was induced in the medium supplemented with TDZ. Pre-treatment temperatures of 4 degrees C and 25 degrees C were more favorable for embryo production than 32 degrees C. Regeneration of androgenic haploid plantlets from cv. SRA 63 of C. clementina is reported here for the first time.