‘Harvestmen’, ‘daddy longlegs’, or ‘harvest spiders’ are all common names of the diverse order Opiliones. There are approximately 6,411 described species.
A ‘typical’ opilionid has:
Opilionids have no silk glands, or venom glands, but possess odorous glands to repel predators.
Other special characteristics of the order include a penis in males and an ovipositor in females, and certain species with an omnivorous diet.