Prickly hairs, spikes, quills, and spines on an animal’s body
help defend it. They can be irritating or painful, or difficult to swallow. Among the ranks of these bristly beasts are animals
whose spines also are venomous.
|A sharp, venomous spine on a stingray’s
tail helps it defend itself from
such as sharks.
Caterpillars of different species, for example, often have
barbed hairs as part of their defense systems. The hairs irritate
predators. Some species’ hairs also are attached to venom glands.
These hairs not only pierce predators, but also inject venom.
Often a predator is jabbed merely by touching the caterpillar.
Some kinds of caterpillars arch their bodies to stab their spines
into a predator as it attacks.
The saddleback caterpillar is a bristly brown caterpillar
with a green “saddle blanket” on its back. When its hairs are
touched, they stick in the predator’s skin and their tips break
off, allowing venom to flow out from the caterpillar’s body through the hollow hairs. Saddlebacks are found in the eastern
United States. A saddleback’s sting causes pain and swelling at
the site of the sting, and can make a person feel nauseated.
Flannel moth caterpillars also have venomous hairs. The
fuzzy caterpillars look soft enough to pet, but their powerful
venom causes severe pain and swelling. Some flannel moth caterpillars
in South America have such strong venom that they can
temporarily paralyze a human. in Brazil, they are known as “fire
beasts” because of their painful sting. Another South American
caterpillar, the larva of the giant silkworm moth, inflicts stings
that can be deadly to humans.
Venomous spines also are found on a number of sea creatures,
such as stingrays. Stingrays are flat-bodied cousins of sharks. They hunt for clams, worms, and other prey on the seabed
in shallow water, and often half-bury themselves in sand and
mud when resting. Their tails are armed with sharp spines that
are notched along their edges like saw blades.
|A large stars-and-stripes toadfi sh swims over a
coral reef. Toadfish use
their venomous spines
against predators, and their camouflaged body
color and spines help them hunt prey.
Stingrays use their spines to defend themselves from predators,
such as sharks. A frightened stingray lashes its spiny tail
over its back to sting its foe. It also stings people who step on it.
Fireworms, some sea urchins, and the crown-of-thorns starfish also rely on sharp, venomous spines for protection. The fireworm
is covered with hollow bristles that break off easily in a
predator’s skin and allow venom to seep into it. The burning pain
that results gives the fireworm its name. A fireworm warns that it
is dangerous by flaring its bristles.
A sea urchin is a prickly pincushion at all times. An urchin’s
spines pierce and break off in a predator’s skin. Venomous
long-spined sea urchins give predators a dose of venom as
well as an injury, because venom flows from the broken spines.
Some species’ spines are covered with venomous skin, which
leaks venom when the spine stabs an animal. The crown-of-thorns
starfish, a relative of urchins, also delivers its venom in
An urchin, which can sense light and dark, can pinpoint its
attacker and then aim its spines in that direction. The most venomous
urchin, called the flower urchin, has nonvenomous spines.
However, it has miniature sets of venomous jaws hidden among
|A lionfish spreads out its venomous spiny fins in
Other species have venomous spines in their fins. Like stingrays,
these fish use their spines only for defense. The weeverfish,
found along British beaches, hunts by lying hidden in the sand
in shallow water. It has venomous spines in its back fin and over
its gills. It doesn’t use these on the shrimp and small fish that it
snaps up as they swim by, but a fish that tries to eat the weeverfish will be confronted by these weapons.
Venomous toadfish nestle in sand in the warm, shallow waters
of Central and South America. Like weevers, they sport
venomous spines on their backs and gill covers. Their drab,
brown-and-gray coloring helps camouflage them as they lie in
wait to catch fish and other small prey with their wide, toothy
mouths. The hollow spines are used only for injecting venom
Another well-camouflaged fish of shallow ocean water is the
warty, slow-moving stonefish. It releases venom when the spines
in its back fin are pressed. The venom shoots along grooves in the spines and into the injury caused by the pointy tips. Stonefish live in parts of the indian and western Pacific oceans. Their
venom is the deadliest of any fish. People get stung when they
accidentally step on a stonefish. Sharks and rays get stung when
they close their jaws on one.
Not all venomous fish are sluggish, bottom-dwelling species.
The gaudy lionfish, with its bright colors and large fins, is a vivid
sight as it swims among other coral reef fish. Its beautiful fins,
however, contain venomous spines. A lionfish uses them to defend
itself and will turn to face a predator, spreading out its spiny
fins in warning.
Worldwide, there are about 1,200 kinds of venomous fish—
more than twice the number of venomous snake species.