Someone just asked me: “I’ve heard that a daddy long leg spider isn’t actually a spider, which seems nuts. Is this true?”
The answer is quite simple…depending upon where you live.
Daddy Long Legs, if you live in the majority of the US, are part of Class Arachnida however Arachnida is not just full of spiders. Arachnida also includes scorpions, mites, pseudoscorpions, and camel spiders. Additionally, class Arachnida contains an Order known as Opiliones…also known as Harvestmen…often called “Daddy Long Legs.” These are Arachnids (have chelicera and 8 legs) but do not meet the other characteristics which define spiders. Spiders are part of the order Araneae.
I could easily write a huge thing about them, but one of my favorite YouTubers created an awesome little video which will clear up this whole thing.
Here is an “interesting” paper regarding the relationships between these different arthropods. Phylogeny & Systematic Position of Opiliones