The duration of prometaphase in Klp67A^S042705/Df(3L)29A6 mutants is shorter (30 min) than in wild type (34 min). The average reorientation period of chromosomes as they traverse the spindle in the mutants is longer than in wild type (~20 min vs 14 min). Unlike in wild-type spermatocytes, chromosomes in Klp67A^S042705/Df(3L)29A6 mutants form poorly defined metaphase plates, which tend to be staggered with the chromosomes only loosely aligned. These chromosomes often do not find stable positions at the spindle equator and may exhibit one or more motions before anaphase onset. Prior to anaphase in Klp67A^S042705/Df(3L)29A6 mutants, homologous chromosomes appear twisted relative to one another; this effect is not seen in wild type. During anaphase, chromosome movement does not occur in a continuous manner and poleward migration velocity is greatly attenuated compared to wild type. In some mutant cells dyads begin the migration poleward but then abruptly halt and remain stationary relative to the spindle pole, exhibiting no further poleward movement before decondensing. In a few cells it appears that disjoined dyads do not undergo any significant anaphase A movement. Nuclear reformation occurs at non-polar locations in 72% of Klp67A^S042705/Df(3L)29A6 mutants.