There are eight species of Brazilian wandering
spider, all of which can be found in Brazil. Some of
the species also can be found throughout Latin
America, from Costa Rica to Argentina, according to
an article in the journal American Entomologist.
Brazilian wandering spiders are large, with bodies
reaching up to 2 inches (5 centimeters) and leg
spans reaching about 6 inches (15 cm).
The species vary in color,
though all are hairy, mostly brown and may have a
black spot on their bellies.
Brazilian wandering spiders' venom is a complex
cocktail of toxins, proteins and peptides, according
to the Natural History Museum in Karlsruhe,
Germany. The venom affects ion channels and
chemical receptors in victims' neuromuscular
systems.
After a human is bitten by one of these spiders, he or
she may experience initial symptoms such as severe
burning pain at the site of the bite, sweating and
goose bumps, Sewlal said. Within 30 minutes,
symptoms become systemic and include high or low
blood pressure, fast or a slow heartbeat, nausea,
abdominal cramping, hypothermia, vertigo, blurred
vision, convulsions and excessive sweating
associated with shock. People who are bitten by a
Brazilian wandering spider should seek medical
attention immediately.
In addition to intense pain and possible medical
complications, the bite of a Brazilian wandering
spider can deliver a long, painful erection to human
males. The venom boosts nitric oxide, a chemical
that increases blood flow. Several studies have
looked at incorporating the venom into drugs for
erectile dysfunction.
However, these bites are rare, and envenomations
are usually mild
"It is unlikely that the spider would inject all of its
venom into you, as this venom is not only needed as
a means of defense but to immobilize prey," Sewlal
agreed. "So if it did inject all of its venom, it [would]
have to wait until its body manufactured more before
it could hunt." That would leave the spider vulnerable
to being attacked by predators.
2)Six-eyed Sand Spider
The Six Eyed Sand Spider
is a medium-sized spider found in deserts and other sandy places in
southern Africa. It is a member of the Sicariidae
family and close relatives of this spider are
sometimes found in both Africa and in South
America. Its nearest relatives are the Recluse spiders
which are found worldwide.
The scientific name for this spider’s family
is which means ‘murderer’ and the spider is
certainly an assassin. It hunts by burying itself in the
sand and waiting for its unsuspecting victim to wander
by at which point it pounces. In trials it was shown that
the venom from a bite was fatal to rabbits in as little as
5 hours.
The venom
of the six-eyed sand spider is a powerful cytotoxin. In
the case of the venom is both hemolytic and
necrotic meaning it causes blood vessels to leak and
destruction of flesh.
There are no confirmed bites in man and only two
suspected ones. However, in one of these cases, the
victim lost an arm to massive necrosis and in the
other, the victim died of massive haemorrhaging,
similar to the effects of a Rattlesnake bite.
3)The Sydney Funnel Web Spider
Bites from Funnel Web Spiders have caused 13
deaths (seven in children). In all cases where the
gender of the biting spider could be determined, it
was found to be the male of the species. Most
victims were young, ill or infirm.
The venom appears to be fairly harmless to many other animals,
including dogs, cats, horses, rabbits, guinea-pigs,
chickens and even cane toads. It has been suggested
that these animals may be resistant to the venoms
effects.
The females venom was thought to be only about a
sixth as potent to humans as that of the male,
however, recent research has proven this untrue. The
bite of a female or juvenile may be serious, however,
considerable variability occurs in venom toxicity
between species.
Early symptoms of a Funnel Web spider bite include
tingling around the mouth and tongue, facial muscle
twitching, nausea, vomiting, profuse sweating,
salivation and shortness of breath. Patients may
rapidly develop agitation, confusion and coma
associated with hypertension, metabolic acidosis,
dilation of the pupils, generalised muscle twitching
and pulmonary edema. Death results from progressive
hypotension or possibly raised intracranial pressure
resulting from cerebral edema.
4)Brown Widow Spider
Like many spiders,
widows have very poor vision, and they move with
difficulty when not on their web. The Brown Widow
spiders have relatively spindly legs and deep, globular
abdomens. The abdomen has one or several red spots,
either above or below. The spots may take the form of
an hourglass, or several dots in a row. The male
widows, like most spider species, are much smaller
than the females and may have a variety of streaks
and spots on a browner, less globular abdomen. The
males are generally less dangerous than the females,
but will bite if the web is disturbed and the spider feels
threatened.
Brown window spider has a
neurotoxic venom. The venom acts on nerve endings
causing the very unpleasant symptoms of
latrodectism . However, brown widow bites are usually
not very dangerous; usually much less dangerous than
those of the black widow. The effects of
the toxin are usually confined to the bite area and
surrounding tissue, unlike the black widow's.Mere
toxicity of the venom is not the only factor in
dangerousness. Brown widow bites are minor
compared to black widow bites because they cannot
deliver the same amount of venom as the black
widow.
5)Black Widow Spider
Black widows are notorious spiders identified by the
colored, hourglass-shaped mark on their abdomens.
Several species answer to the name, and they are
found in temperate regions around the world.
Approximately 5 percent of the reported bites were
fatal prior to the invention of Widow spider antivenom.
Sixty-three deaths were reported in the
United States between 1950 and 1959, most of which
occurred in or around a woodpile or outhouse. But with
the modernization of home plumbing and heating,
Black Widow bites are now very rare.
This spider's bite is much feared because its venom is
reported to be 15 times stronger than a rattlesnake's.
In humans, bites produce muscle aches, nausea and a
paralysis of the diaphragm that can make breathing
difficult; however, contrary to popular belief, most
people who are bitten suffer no serious damage—let
alone death. But bites can be fatal, usually to small
children or the elderly. Fortunately, fatalities are fairly
rare; the spiders are nonaggressive and bite only in
self-defense, such as when someone accidentally sits
on them.
6)Poecilotheria regalis
Poecilotheria regalis also known
as “Indian ornamental”, is a beautiful spider due
to its coloration, pattern and behavior from Southern
India.
The Poecilotheria-genus is well-equiped with
distinctive colors and patterns. Where legpairs and
the pedipalps show an alternating black and white
pattern, the bottomside of legpairs will amaze
you with its bright black and yellow coloration.
Intriguing about the genus is their typical resting
pose. With the first two leg pairs forward, the last two
leg pairs backward and an angry look, they’re sending
a clear message: “Don’t come too close!”
7)Yellow Sac Spider
Its bites effect
Small and innocuous in appearance but capable of
delivering quite a nasty bite, the yellow sac spider is
one to avoid. The spiders of the family
are usually between 5 and 10mm (1/4 to 3/8 ins) long
and are pale yellow or green in colour. They are fairly
widespread occurring from Australia to Canada and
many places in between.
The venom of the yellow sac spider is a cytotoxin,
which means it breaks down cells, possibly causing
necrosis. Bites are characterized by an initial stinging
pain followed by redness and swelling which can
develop into a blister or sore. The bite is often
compared to that of the brown window spider,although it is
less severe and any resulting wound is likely to heal
much faster. Some experts reckon that many
recorded brown window spider bites are in fact sac spider bites
and that these spiders are responsible for more bites
than any other species.
8)Tarantulas
Tarantulas are found across the southern and
southwestern regions of the United States.
Some people keep them as pets.
If a tarantula bites you, you may have pain at
the site of the bite similar to a bee sting. The
area of the bite may become warm and red.
If you are allergic to tarantula venom, these
symptoms may occur:
Breathing difficulty
Loss of blood flow to major organs (an
extreme reaction)
Eyelid puffiness
Itchiness
Low blood pressure and collapse
Rapid heart rate
Skin rash
Swelling at the site of the bite
Swelling of the lips and throat
9)Camel Spider
Camel spiders eat or chew on people while
they sleep. Their venom numbs the area so
people can't feel the bites: Camel spiders
are not venomous , and though their bites
are painful, they are not deadly to humans.
Interesting!!
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