-" the extensive beaklike mouthparts of sucking insects (B250); in mosquitoes (Culicidae - Mosquitoes (Family)) consists of a labium or sheath-like structure enclosing, and acting as a protective sheath for, a group of six stylets. The labium does not pierce the skin when a mosquito bites, while the stylets pierce the skin and form a small duct through which saliva is injected and a canal through which liquid food such as blood is ingested. (D70).