DCutFIG 4: Cuticle plug covering the buccal opening in the dauer larva.

A&B. SEM of mouth region in L2 larva A and dauer larva B showing opening to buccal cavity. (Image source: Riddle, 1988.)
C. Cross-section SEM of L2 larva mouth showing opening to buccal cavity. (Image source: [D. Riddle] N2_L2_28-14-006.)
D. Cross-section SEM of dauer larva showing cuticle flaps creating the plug which occludes the buccal cavity. (Image source: [D. Riddle] CB2620_dauer_69_5-1-021.)

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