Eastern spruce gall adelgid nymphs resemble aphids but lack which feature?

Eastern spruce gall adelgid nymphs resemble aphids but lack which feature?

• A. Cornicles
• B. Wings
• C. Wax secretions
• D. Antennae

Answer: (A)

Distinguishing aphids from adelgids using body features. Aphids normally have cornicles, the pair of tube-like structures on the end of the abdomen that secrete defensive fluids. Eastern spruce gall adelgid nymphs look like aphids but lack these cornicles, so they do not have that posterior tubular feature. That absence is the key identifying clue that separates adelgids from true aphids, even when their overall shape is similar. Wings can vary and aren’t as reliable for this distinction, and wax secretions or antennae aren’t definitive indicators since both groups can show variation in those traits.

Distinguishing aphids from adelgids using body features. Aphids normally have cornicles, the pair of tube-like structures on the end of the abdomen that secrete defensive fluids. Eastern spruce gall adelgid nymphs look like aphids but lack these cornicles, so they do not have that posterior tubular feature. That absence is the key identifying clue that separates adelgids from true aphids, even when their overall shape is similar. Wings can vary and aren’t as reliable for this distinction, and wax secretions or antennae aren’t definitive indicators since both groups can show variation in those traits.