Daddy longlegs (aka harvestmen, Opiliones) are living fossils. They originated 350-400 million years ago and haven’t fundamentally changed since then. These were my favorite arachnids when I was a kid.
Here’s a few interesting facts from the “Amazing Arachnids”book.
- They are unusual among arachnids because they eat solid food, which also exposes them to parasites
- They are not venomous and have limited weapons to use against predators. Their main “weapon” is cryptic coloration but some rapidly bob up and down.
- They can also lose a leg, which can twitch for nearly an hour
- Many females will hide their eggs. Once mated and with male in tow (legs are looped) to guard her she looks for the perfect spot
- Depending on their location, eggs can open in 30 days or some overwinter
- Unlike other arachnids who have 8 eyes, daddy longlegs have only 2
These spiders are sometimes confused with Cellar spiders, but Harvestmen also do not use silk.