Are daddy long legs poisonous

1. What people mean when they say “daddy long legs” — three different animals, three different realities

The nickname “daddy long legs” is applied loosely to at least three unrelated groups: harvestmen (Order Opiliones), crane flies (insects, Tipula spp.), and pholcid cellar spiders (Family Pholcidae), and conflating them causes most confusion in reporting and folklore ^{[1] [4] [3]}. Harvestmen are not true spiders and lack venom glands, crane flies are insects that do not possess venom, and pholcids are true spiders that do produce venom like most spiders but not at levels dangerous to people ^{[1] [2] [3]}.

2. What the science says about venom and toxicity for each group

Harvestmen (Opiliones) have no venom glands and instead may use foul-smelling defensive secretions that can deter predators but are not recorded as a human medical threat ^{[1] [3]}. Crane flies likewise do not produce venom; they are harmless insects often mistaken for giant mosquitoes and pose no toxic threat to people ^[1]. Pholcid or “cellar” spiders do produce venom with enzymes useful for breaking down invertebrate prey, but experiments and expert reviews show their venom is relatively weak and not medically significant for humans; there is no reliable evidence of pholcid bites causing harmful reactions in people ^{[5] [2] [6] [3]}.

3. The myth’s anatomy: how “too-short fangs” and “most venomous” became folklore

The urban legend that daddy long legs are the world’s deadliest spiders but cannot bite humans because of short fangs likely arose from a muddling of observations—pholcids can subdue and sometimes consume other spiders, including more notorious species, which may have suggested potent venom, and harvestmen’s defensive chemicals were misunderstood as “poison” ^{[7] [3]}. Scientists and museums have repeatedly debunked the claim, noting that the tale mixes different taxa and misattributes venom potency; research shows pholcid venom is mild even to insects and there’s no documented case of dangerous human envenomation by these spiders ^{[1] [2] [3]}.

4. Notable demonstrations and limits of evidence

Television demonstrations—most famously a 2004 MythBusters segment—showed a pholcid biting a human hand under contrived conditions, indicating these spiders can penetrate human skin and deliver venom, but such bites produced only minor effects and do not validate the “most venomous” claim ^{[5] [7]}. Laboratory comparisons also put pholcid venom far below medically significant species like black widows, and authoritative institutions (universities, conservation departments) conclude the venom is not harmful to humans ^{[3] [6] [2]}. Reporting is consistent across multiple university and museum sources that there is no reliable evidence of pholcid bites causing serious human injury ^{[2] [1]}.

5. Practical takeaways and competing viewpoints

From a practical standpoint, these creatures are generally harmless: harvestmen and crane flies pose no venom risk, and cellar spiders, while venomous to invertebrates, are not dangerous to people; some experts still caution that any spider can bite if provoked, so avoid handling them directly ^{[1] [6] [8]}. Skeptics point to persistent folklore and the dramatic appeal of “secretly deadly” animals as reasons the myth won’t die, while arachnologists emphasize taxonomy and empirical venom testing to correct public misconceptions ^{[3] [4]}.

6. Bottom line

The claim that “daddy long legs” are poisonous in the sensational sense is false: the term covers several animals, most have no venom and the one group that does (pholcid cellar spiders) has venom that is weak and not known to cause medically significant harm to humans ^{[1] [2] [3]}. Where reporting is vague or sensational, return to taxonomy and peer-reviewed or institutional sources—those consistently reject the “most venomous” urban legend ^{[2] [6]}.