substage of immediately preceded by immediately precedes embryonic stage late embryonic stage embryonic stage 17 larval stage first instar larval stage L1 UBERON:8000000 Temporal ordering number - 410. FlyBase_development_CV FBdv:00005337 The first larval instar begins at hatching and ends at the first larval molt. Anterior spiracles are not yet present; posterior spiracles have two openings each. Salivary glands are very small and all cells are uniform in size. Mouth hooks typically have one tooth. Duration at 25 degrees C: approximately 25 hours (24-49 hours after egg laying; 0-25 hours after hatching). first instar larva second instar larval stage life stage embryonic stage 17(iv)