A field worker collects larvae from a pond and observes them lying horizontally, parallel to the water surface, with no connection between their posterior end and the surface film except a single breathing opening flanked by palmate hairs. The specimen belongs to:
- A Aedes
- B Culex
- C Anopheles ✓
- D Mansonia
Correct answer: C. Anopheles
Explanation
Anopheline larvae lack a siphon and therefore float parallel to the water surface, respiring through spiracles directly from the air, with palmate hairs helping them maintain this position. Culex and Aedes larvae hang head-down at an angle attached to the surface by their siphon, while Mansonia larvae pierce aquatic plants with a modified serrated siphon for oxygen.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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