The terms venomous and poisonous
are often used interchangeably, but incorrectly. There is, in fact, a
difference between a venomous insect and a poisonous insect. Both venomous and
poisonous spiders produce a toxin that is injurious or even lethal to another
organism. However, the real difference between the two terms involves how that
toxin is delivered.
The Myth that the “Daddy Longlegs” Spider is Venomous is absolutely
false. In response to this Myth, there are several
things that must be said: First
of all, there are actually three different kinds of critters called the daddy long
leg. This common name is most usually used to describe Opiliones, aka
harvestmen. Opiliones are arachnids, but not spiders. They have no venom glands
at all, and are absolutely not venomous. The nickname can also refer to a crane
fly, which is a true fly and a member of the order Diptera. Crane flies do not
pose a threat, either. Now, sometimes, the name is used for another group of
arachnids, the spiders of the family Pholcidae. These spiders are also called
cellar spiders.
However, cellar spiders do
have venom glands. But there is no scientific evidence whatsoever to confirm
that their venom can harm a human being. No studies have been done on cellar
spider venom to measure its toxicity to people.
While Pholcid spiders do have short fangs, they are not
smaller than other spiders that have been known to bite humans. The cellar
spider's fangs are similar in structure to those of a brown recluse spider,
which we know can and does bite humans, and is deadly to humans in certain
circumstances. There is no evidence or proof to the claim that their fangs are
too short to bite a person.
In fact, the show Mythbusters (on
the Discovery Channel) tackled this daddy longlegs legend back in 2004. The
show’s host Adam Savage received a spider bite of a cellar spider. Providing
proof that a daddy longlegs spider is capable of breaking human skin. However,
nothing more than a very mild, short-lived burning sensation occurred because
of said bite. Analysis of the daddy longlegs' venom revealed it's nowhere near
as potent as venom from a black widow spider.
Thus said, you really don't need to worry about daddy longlegs, of any
variety.
So. have
you heard the myth? “The Daddy-Longlegs are one of the most
poisonous spiders, but their fangs are too short to bite humans.” This little
lie has been making the rounds for years. To clarify it that it is, indeed,
very untrue, I first need to explain several facts.
The animals: 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. In the animal class
Arachnida, there are several lower level divisions called Orders. Scorpions are
in the Order Scorpiones, spiders are in the Order Araneae, ticks and mites are
in the Order Acari.
The creatures most correctly
called daddy-longlegs are in their own separate Order which is Opiliones.
Common names for this Order are 1) daddy-longlegs, 2) harvestmen and 3)
opilionids. They are characterized by having one basic body segment which shows
segmentation on the posterior portion, at most 2 eyes and all 8 legs attach to
the pill-like body segment. They are usually found under logs and rocks, prefer
moist habitat although they can be found in the desert, often have long
flexible legs (in the temperate Northern hemisphere but there are also
short-legged daddy-longlegs) and they do not produce silk so therefore they are
never found in webs unless they are being eaten by other spiders. Because they
are found under logs and other stuff which people most often are not turning
over, most folks don't run into them very often.
Another creature often called
daddy-longlegs are actually spiders. These long-legged spiders are in the
family Pholcidae. Previously the common name of this family was the cellar
spiders but arachnologists have also given them the nick name of daddy-longlegs
spiders because of the confusion generated by the general public. Because these
arachnids are spiders, they have 2 body
parts (cephalothorax and abdomen), 8 eyes, the abdomen shows no evidence
of segmentation, have 8 legs and make webs out of silk. This is most probably
the animal to which people refer when they tell the tale because these spiders
are plentiful especially in cellars (hence their common name) and are commonly
seen by the general public. The most common pholcid spiders found in U.S. homes
are both European immigrants. Pholcus phalangioides is a uniformly grey
spider with rectangular, elongate abdomen and is found throughout the U.S. Holocnemus
pluchei which looks the same but has a brown stripe on the ventral side
(the belly side - which is typically directed upwards since the spider hangs
upside down in its web) which covers its sternum and is a stripe on the
abdomen. These spiders are very common along the Pacific Coast, and into the
southwest deserts.
There is no truth to a possible envenomation. The
spider called the Daddy-longlegs (Opiliones) - who make their living by
eating decomposing vegetative and animal matter although are opportunist
predators if they can get away with it. They do not have venom glands, fangs or
any other mechanism for chemically subduing their food. Therefore, they do not have
poison and, by the powers of logic, cannot be poisonous from venom. Some have
defensive secretions that might be poisonous to small animals if ingested. So,
for these daddy-long-legs, the tale is clearly false.
Here, the myth is incorrect at
least in making claims that have no basis in known facts. There is no reference
to any pholcid spider biting a human and causing any detrimental reaction. If
these spiders were indeed deadly poisonous but couldn't bite humans, then the
only way we would know that they are poisonous is by milking them and injecting
the venom into humans. For a variety of reasons including Amnesty International
and a humanitarian code of ethics, this research has never been done.
Furthermore, there are no toxicological studies testing the lethality of
pholcid venom on any mammalian system (this is usually done with mice).
Therefore, no information is available on the likely toxic effects of their
venom in humans, so the part of the myth about their being especially poisonous
is just that: a myth, a flat lie. There is no scientific basis for the
supposition that they are deadly poisonous and there is no reason to assume
that it is true.
As for their fangs being too
short to penetrate human skin? Pholcids do have short fangs, which is called
uncate because they have a secondary tooth which meets the fang like the way
the two grabbing parts of a pair of tongs come together. Brown recluse spiders
similarly have uncate fang structure and they are able to bite humans. There
may be a difference in the musculature that houses the fang such that recluses
have stronger muscles for penetration because they are hunting spiders needing
to subdue prey whereas pholcid spiders are able to wrap their prey and don't
need as strong a musculature. So the facts have no scientific basis.
The Myth is utterly false:
For true daddy-long-legs, the
opilionids, the myth is certainly not based on known scientific facts. There is no worry that the spider commonly
called a – daddy longlegs – is a threat to people.
And finally another Myth is being
re-circulated today, that needs a comment. The Blush spider ‘Arachnius
gluteus’ is a hoax. Commonly
called the Spider under the Toilet Seat: In
September of 1999, when it first appeared, and has resurfaced many times since
then, that last one, I believe was in October this year (2014), is an spider
hoax. Circulating on the internet, about an article allegedly published in the
Journal of the United Medical Association regarding an allegedly deadly South
American spider, Arachnius gluteus, which was supposedly brought into
Chicago, had supposedly killed several women who had visited Big Chappie's
Restaurant in Blare Airport. This hoax was widely circulated and passed along
by concerned people. A website link was erected to debunk this hoax and
received 49,000 hits within 2 weeks, and though that web-site is no longer up,
concerned people have begun calling law enforcement personnel to complain that
they have one in their residences. Now, there have been several emails
requesting information as what the spider looked like because the concerned population.
The creator of the hoax purposely filled it with incorrect information so that
if the reader checked into any bit of it, a red flag would arise because there
would be no credibility to the citation of information (there exists no medical
journal with that name, there is no spider named Arachnius, and there is
no Blare Airport, etc.) He wrote the hoax to show that 1) people are
gullible, 2) that the internet is a frighteningly fast way to spread
misinformation, and, 3) people forward on information without checking its
veracity. Though he never expected this to spread so quickly and so
widely. The account of the anatomy of the first hoax is detailed in
the article: Vetter, R. S. and P. K. Visscher. 2000. Oh, what a tangled web we weave: the
anatomy of an internet spider hoax. American Entomologist 46: 221-223.
In 2003, this hoax was
resuscitated and modified where it was shifted to north Florida, the restaurant
was now the Olive Garden and the spider was Telamonia dimidiata.
The resuscitator of this hoax at least did a little homework because this is
the scientific name of an actual jumping spider from India, Bhutan and Sumatra,
however, it is harmless or at least there is no reason to suspect that it is
dangerous (especially considering that the rest of the message is a recycled
hoax anyway.)
Finally, recirculated in October where
the name of the Spider is Parasteatoda tepidariorum. This is
the common house spider. The setting was switched to Reno, Nevada, the
Restaurant, ‘The Clause Inn,’ (which equally does not exist) and the effect of
this bite was quite ghastly. I was quite
amused reading this hoax. The laughter emitting from me could be heard several
houses away from my residence. The rest
of the hoax was a basic rehash of the original hoax that was started with the Telamonia dimidiata. Needless to say, people should
really check the facts, before becoming overly frightened. Indeed, red flags popped up the moment that I
read the description of this Spider, being: bright neon red, with light blue
bottom legs and two antennae. - Bird
