There seems to be a sort of public hysteria regarding them but there isn't any type of scientific data to back most of it up. So, that means that a good portion of the information that exists in society is false and a lot of it is just plain ridiculous.įirst, let's start with the most commonly seen, daddy-longlegs. The first issue that needs to be cleared up is that there are two totally different critters that people refer to as "daddy-longlegs". One is a true spider while the other is not. The two are the Order Opiliones and the Family Pholcidae in the Order Araneae.įirst are the Order Opiliones because they are probably seen more often than Pholcidae. Opiliones in the scientific community are known as Harvestmen. Other common names are Daddy-long-legs, Granddaddy-long-legs, Opilionids, and Shepherd Spiders, among a few others. Harvestmen are arachnids but they are not spiders. As mentioned above Harvestmen are in the Order Opiliones while spiders are in the Order Araneae. One obvious difference between Harvestmen and spiders is that the body shape of Harvestmen appears to be only one segment. However, Harvestmen, as well as spiders, actually have two main body segments, the cephalothorax (head end) and the abdomen (tail end). It's just that in Harvestmen the "junction" between the two parts is not nearly as distinct as in spiders and is usually not noticeable at all at first glance, so it appears as only one body segment. Another anatomical feature of Harvestmen that is also shared with spiders is that they both have eight legs, which is probably the main cause of confusion between the two. But, that is about where the similarities end. To start, Harvestmen have two eyes where spiders can have no eyes on up to eight. Harvestmen do not have silk glands so they cannot make webs but obviously spiders can make webs. Many species of Harvestmen are omnivorous and mainly eat insects and different kinds of plant material but will also eat fecal matter from birds and other critters. Another BIG difference between Harvestmen and spiders is the fact that Harvestmen have no fangs and consequently have no venom. All spiders possess fangs and venom, except the family Uloboridae (which does not possess venom and instead relies on extensively wrapping prey in silk). Harvestmen have what are called Chelicerae, which in spiders they are hollow in order to deliver venom but in Harvestmen they are primarily used to grasp food (see here and here). There is a myth that Harvestmen are among the most venomous and toxic of all arachnids but that their fangs are to small to penetrate our skin. Obviously from the information presented here, on other websites, and in scientific literature, they CANNOT be among the most venomous and toxic of all arachnids if they have no fangs and no venom. So, Harvestmen are completely harmless to humans other than they can give off a foul smelling liquid as a defense mechanism. The Family Pholcidae in the Order Araneae are also sometimes called daddy-longlegs but are more correctly known as cellar spiders.Ĭellar spiders are true spiders. They have a distinct cephalothorax and abdomen, eight eyes, eight legs, fangs and venom, and make webs. They are also often mistaken for the Brown Recluse spider. However, the Brown Recluse does not have the extremely long legs that Cellar spiders do and the Brown Recluse eye arrangement is different.īelow is a comparison between Cellar spiders and Brown Recluse spiders : They both have a similar shape and similar color. See below for more detail on the Brown Recluse. The Cellar spider also has a dark patch but the shape is not consistent nor is it distinctive. In the second set of pictures you can plainly see the difference in leg length as compared to the body. The Cellar spider has much longer legs in relation to it's body.Īlso note that the range for the Brown Recluse is a lot less and doesn't cover near the area that the Cellar spider's range does.
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