What is a key characteristic of sawflies compared to caterpillars?

The key characteristic of sawflies compared to caterpillars is that sawflies have a single pair of large eyes. This distinction is important in recognizing these insects. Sawflies belong to the order Hymenoptera and are typically characterized by their adult forms, which have well-developed compound eyes.

In contrast, caterpillars, which are the larval forms of moths and butterflies (order Lepidoptera), exhibit different anatomical features. While both groups can appear similar, the single pair of large, compound eyes in sawflies helps to differentiate them. This aspect of their anatomy is crucial for adult identification, as it influences their behavior and ecological interactions.

As for the other options, sawflies and caterpillars have significant differences in body structure, particularly regarding the number of prolegs and the presence of abdominal legs. Caterpillars typically feature multiple pairs of prolegs and may have well-defined segments with additional legs, while sawflies lack the abdominal legs that are characteristic of caterpillars. The suggestion that sawflies are always stinging insects is misleading, as not all sawflies possess a stinger, and the mention of a specific number of eye pairs or prolegs does not universally apply across all species of these insects.