Previously the common name of this family was the cellar spiders but arachnologists have also given them the moniker of "daddy-longlegs spiders" because of the confusion generated by the general public. These long-legged spiders are in the family Pholcidae. Scorpions are in the Order Scorpiones, spiders are in the Order Araneae, ticks and mites are in the Order Acari.Īnother creature often called daddy-longlegs is actually a spider. In the animal class Arachnida, there are several lower level divisions called Orders. Most folks who retell this tale have no idea that they are referring to two completely separate groups of animals: "daddy-longlegs" and "daddy-longlegs spiders". But a mongoose considers cobras to be lunch because they are immune to the venom. Cobras are venomous because they have venom which can have a negative effect on some mammals such as humans so the effect in humans is toxic. The correct term for having a negative effect on a target organism is "toxic".Poison oak causes dermal injury in humans but deer readily eat the plant so "poisonous" does not imply universal effect.
Similarly, "poisonous" is an anatomical description of an organism which produces a compound in a gland that is usually transferred by contact or ingestion.There are many venomous animals whose venom works on their insect prey but are harmless to humans. However, "venomous" is an anatomical description and does not necessarily imply universal effect. "Venomous" means an organism has specific glands for the production of venom, ducts to convey the venom through hardened structures (fangs, sting) for hypodermic introduction into a target organism.One area of confusion is with the terms "venomous" and "poisonous" which are not interchangeable.This is incorrect, but to clarify it, several points need to be explained first. I have heard it repeatedly in the United States and even heard a schoolteacher misinforming her class at a museum in Brisbane, Australia. This tale has been lurking around for years.
Have you heard this one? "Daddy-Longlegs are one of the most poisonous spiders, but their fangs are too short to bite humans"