The term “granddaddy long legs” often causes confusion, as it is commonly applied to a variety of long-legged creatures. This widespread ambiguity makes it difficult to ascertain which animal is being discussed when the common name is used. While some may associate the name with crane flies, which are insects, it primarily refers to two distinct groups of arachnids. This article aims to clarify the identities of these arachnids and their relationship to true spiders.
The Two “Granddaddy Long Legs”
The popular term “granddaddy long legs” typically refers to two arachnid groups: harvestmen and cellar spiders. Harvestmen (order Opiliones) are not true spiders. They are a distinct order within the class Arachnida, which also includes scorpions and mites. They are related to spiders but represent a separate evolutionary lineage.
Conversely, cellar spiders (family Pholcidae) are true spiders, belonging to the order Araneae. These arachnids are frequently found indoors in undisturbed areas such as basements and cellars, accounting for their common name. Both harvestmen and cellar spiders share notably long, thin legs, contributing to the interchangeable use of the “granddaddy long legs” moniker.
Key Distinctions
Distinguishing harvestmen from cellar spiders involves anatomical and behavioral differences. A primary distinction lies in their body structure; harvestmen have a fused body that appears as a single oval segment, unlike spiders which possess two distinct body segments: the cephalothorax and the abdomen.
Harvestmen typically have two eyes, usually situated on a raised mound called an ocularium, often appearing in the middle of their body. In contrast, cellar spiders generally have eight eyes, often arranged in two clusters of three eyes with an additional pair in the middle, although some species may have six eyes. A significant behavioral difference is that harvestmen do not produce silk or build webs. Cellar spiders, being true spiders, construct loose, irregular webs to capture prey.
Common Myths and Safety
Numerous misconceptions surround both types of “granddaddy long legs,” particularly regarding their potential danger to humans. A prevalent myth suggests that harvestmen possess potent venom but cannot bite humans due to short fangs. However, harvestmen generally do not have venom glands at all. Their mouthparts are designed for grasping and tearing food, and they are typically too small or weak to penetrate human skin.
Cellar spiders, while being true spiders, are also subject to similar myths about extreme venom potency. Like most spiders, cellar spiders do possess venom, but their venom is not considered medically significant to humans. Although their fangs are short, they are capable of penetrating human skin, contrary to the myth. Both harvestmen and cellar legs are generally harmless to humans and do not pose a significant threat.