Spiders and scorpions are placed in the same class because they both have:

1. Spiders and scorpions both belong to the class Arachnida. 2. The defining feature of that class is a pair of chelicerae, the front appendages used for feeding. 3. Three pairs of legs, a pair of wings and three body parts are all characteristics of class Insecta. 4. Two pairs of antennae is a characteristic of class Crustacea. 5. Arachnids in fact carry four pairs of legs and two body parts, which is another way they separate from insects. _Source: NECTA CSEE 2022 Biology 033, Question 1: Multiple Choice Items, item (viii)_