Simplify the following text for a Grade 7 native English-speaking person.
Original: Although they belong to the class of arachnids , harvestmen are not spiders , which are of the order Araneae rather than the order Opiliones .
Simplified: Although they belong to the class of arachnids , harvestmen are not spiders . They belong to the order Opiliones or Phalangids .