substage of immediately preceded by late extended germ band stage developmental stage extended germ band stage embryonic stage 12 embryonic stage 13 Stage 13 begins at the completion of germ-band retraction, when the prospective anal plate occupy the posterior pole. The dorsal ridge becomes apparent externally; the clypeolabrum retracts, leaving a triangular shaped gap at the anterior pole; the labium moves to the ventral midline. This stage ends when head involution begins. Duration at 25 degrees C: Approximately 60 minutes (560-620 minutes after egg laying). contracted germ band stage Temporal ordering number - 340. FBdv:00005328 FlyBase_development_CV dorsal closure stage