The sawtooth grain beetle is identified by saw-toothed projections on its sides. How many are there on each side?

• A. Two
• B. Four
• C. Six
• D. Eight

Answer: (C)

The trait being tested is a distinctive surface feature used to identify the sawtoothed grain beetle: the rows of tooth-like projections along the sides of the thorax. For this beetle, there are six saw-toothed projections on each side. This six-per-side pattern is a reliable identifying clue, more specific than overall size or color, and helps distinguish it from other stored-product beetles that don’t match this exact arrangement. So when you see six teeth on each side, that points to the sawtoothed grain beetle. Counts like two, four, or eight don’t align with this species’ characteristic pattern.