Culicinae larvae lay at what angle to the water surface?

• A. 45 degree angle
• B. 0 degree
• C. 30 degree
• D. 60 degree

Answer: (A)

The key idea is how mosquito larvae position themselves at the water surface, which helps identify the genus. Culicinae larvae, such as Culex and Aedes, typically rest at about a 45-degree angle to the water surface. This angled posture positions their breathing siphon upward through the surface while the body tilts downward, making them look inclined rather than flat against the surface. This is a useful field cue that distinguishes them from Anopheles larvae, which tend to lie parallel to the surface. The angles of 0, 30, or 60 degrees aren’t the standard resting posture associated with Culicinae in practical observations, so 45 degrees is the best choice.