Diagnostic differences
Spiders have eight legs, two body segments (cephalothorax and abdomen), no antennae, and no wings. Insects have six legs, three body segments, antennae, and usually wings.
Spiders breathe through book lungs and tracheae; insects through a tracheal system only.
References
- [1]Spider Myths - Burke Museum, University of Washington. Accessed June 2026.
Related in Myths vs. facts
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