Associate Certified Entomologist (ACE) Practice Exam

Which of the following is NOT a neonicotinoid?

1. Clothianidin

2. Dinotefuran

3. Spinosad

4. Imidacloprid

The correct answer is: Spinosad

Neonicotinoids are a class of neuro-active insecticides modeled after nicotine, and they primarily work by targeting the nicotinic acetylcholine receptors in insects, leading to paralysis and death. The correct choice in this question is Spinosad, which is not a neonicotinoid. Spinosad is derived from the fermentation of a naturally occurring soil bacterium and acts differently compared to neonicotinoids. It affects the insect's central nervous system by causing rapid excitation leading to paralysis and ultimately death, but it does not target the same receptors as neonicotinoids. On the other hand, Clothianidin, Dinotefuran, and Imidacloprid are all part of the neonicotinoid family. They share a similar mode of action, which specifically involves the agonism of neuronal receptors. This highlights the significant difference between Spinosad and the other three chemicals in their classification and mode of action against pests.