Have you heard this one before? “Daddy long legs are the most poisonous spider but their mouths are too small to bite”. If I had a nickel for every time I’ve heard it, I’d be rich. Ok…not rich…but I think you get the point. Unfortunately, this is one of those really common tales that have no merit. In fact, there are several things wrong with the statement.
First, daddy long legs aren’t spiders at all. What’s the difference? Spiders, daddy long legs, scorpions, ticks and mites are all Arachnids but they belong to different orders. Spiders belong to the Order Araneae while daddy long legs, often called harvestmen, are in the Order Opiliones. Although they look similar, there are several differences in their body structure. The body of a spider has two regions: the cephalothorax (head and thorax) and abdomen. Spiders usually have eight eyes, eight legs, two small leg-like palps, a fang and spinnerets. In daddy long legs, the head, thorax and abdomen are fused into one body part. They have two eyes, eight really long, slender legs, and two palps. Two features that truly separate daddy long legs from spiders are that daddy long legs do not have spinnerets to produce silk nor venom to subdue prey. The family Pholcidae includes a species of spider that is commonly called “cellar or daddy long leg” that is a true spider.
Daddy Long Leg vs Daddy Long Leg or Cellar Spider
Secondly, daddy long legs are not poisonous. The words poisonous and venomous are often confused or used interchangeably, however, the meanings are different. Poisonous generally refers to something you consume or touch to get the toxins. An example would be eating poison mushrooms or touching poison ivy. Venomous refers to animals that inject venom by biting or stinging, for instance bees, some snakes, and some spiders. Daddy long legs are not poisonous and do not have venom.
Daddy long legs are predators and scavengers. These beneficial animals eat spiders and insects, including insect pests like aphids, and scavenge on dead insects. Their mouthparts are designed to hold prey while they eat, therefore, they cannot bite pets or humans.
So the next time you hear someone say daddy long legs are “the most poisonous spider,” you can let them know the truth that these animals aren’t really spiders at all and they are not poisonous or venomous. They are fascinating, harmless, beneficial creatures.