Abnormality in the testes of the male flies generated from crossing bam-Gal4 males with Gudu RNAi-2 females. A and B are phase contrast images of testes squash showing testis-specific knockdown of Gudu causes individualization defects in spermatids (B, arrowhead). The defects appeared after meiosis, because the characteristic 1:1 ratio of white nucleus and associated dark mitochondria nebenkern is retained (A, arrowhead). Rhodamin-conjugated phalloidin staining of F-actin revealed the disorganized ICs (C, arrowhead). Scale bar: A and B, 10 μm; C, 40 μm.