Page 56 - Fish and Amphibians (Britannica Illustrated Science Library)
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52 DIVERSITY                                                                                                                                                                                           FISH AND AMPHIBIANS 53




          Danger in the Water                                                                                                              Deadly Weapons                                     Deadly Delicacy


                                                                                                                                           Each spine is covered from base to tip             In Japan the fugu, or puffer fish, is a succulent but lethal delicacy.
                here are poisonous fish in all the seas in the world. The toxic                                                            with a sheath. When the spine pierces,             It contains tetratoxin, a deadly poison. Nonetheless, its flesh is so
                                                                                                                                                                                              delicious that Japanese gourmets, even at the risk of their lives,
                                                                                                                                           the pressure causes the poison gland
                substances they produce are usually not meant for threatening                                                              within to release its contents.         Covering   consider fugu the king of fish. To prepare this high-risk dish, chefs
          T humans but for defending themselves from larger                                                                                                                                   must have a certificate from a special school that teaches the
                                                                                                                                                                                              preparation of fugu.
          aquatic predators. Although some species of puffer fish                                                                                                           Poison
                                                                                                                                           THIRTEEN DORSAL SPINES           gland
          have poisonous flesh, in Japan they are considered                                                                               The fiercer the attack, the more
          a delicacy when properly prepared.                                                                                               damaging are the wounds they
                                                                                                                                           inflict. They can do worse damage
                                                                                                                                           if the spine breaks and sticks   Spine of fin
                                                                                                                                           in the victim's body.
          A Swimming Fortress
                                                                                                                                                                The poison gland lies along                                   INTESTINE
          Red lionfish, also called scorpion fish, are fascinating sea                                                                                          the inside of a long central                                  The puffer fish's
          creatures found in aquariums all over the world. They belong to                                                                  Base of spine        groove and is covered with                                    intestinal wall is also
                                                                                                                                                                glandular tissue that secretes                                poisonous.
          the family Scorpaenidae, which includes fish that have spines and
                                                                                                                                                                the venom.
          venom, such as the spotted scorpion fish. The dorsal fin of the red
          lionfish has spines containing small sacs of potent venom, which it
          uses in self-defense. It has a long body with high, wide fins. The                                                                                                                                                  OVARY
          potency of the venom depends on the species.                                                                                                                                                                        The most toxic of
                                                                                                                                                                                                   STOMACH                    the internal
                                                                                                                                                                                                   When the fish takes in     organs
                                                                                                                                                                                                   water, the stomach
                                                                                                                                                                                                   swells and causes the
                                                                                                                                                                                                   fish to expand.
                                                                                                                                                                                                                              LIVER
                                                                                                                                                                                                                              Highly poisonous;
                                                                                                                                                                                                                              compressed when
                      RED LIONFISH
                                                                                                                                                                                                                              the stomach
                      Pterois volitans                                                                                                                                                                                        expands
          Habitat       Indian and Pacific
                        oceans, Sri Lanka
          Largest size  15 inches (38 cm)                                                                                                                                                              Living Rock
          Family        Scorpaenidae
                                                                                                                                                                                                       Spotted scorpion fish belong to another group of the
                                                                                                                                                                                                       Scorpaenidae family. Buried in the sand along ocean
                                                                                                                                                                                                       beaches, their strong, thick spines can pierce footwear
                                                                                                                                                                                                       when stepped on. They can live up to four months
                                                                                                                                                                                                       eating only the fish that swim near their mouths.
                 LIKE A PEACOCK
                 Lionfish are highly sought after
                 for aquariums because of their                                                                                                                                                        Pressure on the spines opens  Poisonous
                 attractive coloring. This one is                                                                                                                                                      the sacs of poison. Through  spines
                 spreading its pectoral fins like a                                                                                                                  CAUDAL FIN                        channels in the middle of the
                 peacock's tail.                                                                                                                                     Its showy colors                  spines, the poison is injected
                                                                                                                                                                     frighten predator                 into deliberate or accidental
                                                                                                                                                                     species with the coded            aggressors.
                                                                                                                                                                     message: “I'm
                                                                                                                                                                     poisonous!”





                                                                                                                                                                                         SPOTTED SCORPION
                                                                                                                                                                                         FISH
                                                                                                                                                                                         Scorpaena plumieri



                                                                           TWO PECTORAL
                                                                           SPINES                                                   THREE ANAL
                                                                           Appendages below the mouth                               SPINES           1,200 times
                                                                           are used for attacking smaller                           The first three spines
                                                                           fish or crustaceans by rushing                           of the anal fin point
                                                                           against them head-on. When it                            downward.           The relative potency of the venom of a
                                                                           sees potential prey, it pounces.                                            puffer fish compared with cyanide. This
                                                                                                                                                         gives an idea of its killing potential.
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