Arachnida
Definition of Arachnida as it relates to Animals, Arachnids, Opiliones, Prostigmata, Spiders
Arachnida, as a part of the Spiders category, encompasses organisms with two main body segments, no antennae, and simple eyes. They possess four pairs of legs and utilize book lungs or tracheae for respiration. Arachnids exhibit a diverse range of forms, including harvestmen (Opiliones), ticks and mites (Prostigmata), and true spiders, which are distinct from other arthropods in the Animals/Arachnids class. Members of this subcategory excel in various habitats worldwide and play crucial ecological roles as predators or scavengers.