Gurnards, Flatheads, Scorpionfishes, and Relatives: Scorpaeniformes

views updated


LINGCOD (Ophiodon elongatus): SPECIES ACCOUNTS


The characteristic that gurnards, flatheads, scorpionfishes, greenlings, and sculpins have in common is a bone that connects the bones under the eye with the front of the gill cover. In all but one species, a bony ridge below the eyes makes the head look armored. Flatheads and flying gurnards have large pectoral (PECK-ter-uhl) fins, the pair that corresponds to the front legs of four-footed animals. These fishes use the rays, or supporting rods, of these fins to "walk" on the sea floor. All scorpionfishes have sharp spines on their bodies. Some of these fishes display bright warning colors and are highly venomous, venom being poison made by the animals. Greenlings and sculpins have a flat head and large pectoral fins. They have no swim bladder, an internal sac that fishes use to control their position in the water.


Gurnards, flatheads, scorpionfishes, greenlings, and sculpins live in the Indian, Pacific, and Atlantic oceans.


Most gurnards, flatheads, scorpionfishes, greenlings, and sculpins live near the shore, but some live in deep water. Some of these fishes live in mud or sandy bottoms. Others live in rocky habitats and coral reefs.


Gurnards, flatheads, scorpionfishes, greenlings, and sculpins eat crustaceans, such as crabs and shrimp, and smaller fishes. Crustaceans (krus-TAY-shuns) are water-dwelling animals that have jointed legs and a hard shell but no backbone. Some sculpins eat seaweed.


Gurnards and flatheads lie and wait to ambush their prey, or animals hunted and killed for food. Little is known about the reproduction of flatheads and gurnards. They produce free-floating eggs. Some flatheads begin life as males and become females as they grow older.

Scorpionfishes can disguise themselves as leaves or rocks. Some scorpionfishes bury themselves in the sand. Most scorpionfishes live alone except to form mating groups. In many species the male places sperm in the female, and then the female squeezes out the eggs in a jellylike mass that floats at the surface. Other scorpionfishes scatter their eggs, which hatch into free-floating larvae. Larvae (LAR-vee) are animals in an early stage and must change form before becoming adults.


Scorpionfish venom affects both the nervous system and the blood vessels and has caused many human deaths. The effects of the venom are lessened if the wounded area is soaked in very hot, but not boiling, water.


The first red lionfish to live in the Atlantic Ocean were swept there when a home aquarium in Florida was shattered by Hurricane Andrew in 1992.

Sculpins and greenlings feed by pouncing on and swallowing their prey whole or by sucking in the prey with a stream of water. Most greenlings and sculpins lay masses of eggs that always stick to each other but not always to the surface on which they land. Male sculpins and greenlings guard their egg masses.


Flatheads, greenlings, and sculpins are eaten. Lionfishes, scorpionfishes, and sculpins are popular in aquariums.


The World Conservation Union (IUCN) lists one species of gurnards, flatheads, scorpionfishes, greenlings, and sculpins as Extinct, three as Critically Endangered, two as Endangered, and five as Vulnerable. Extinct means no longer in existence. Critically Endangered means facing an extremely high risk of extinction in the wild. Endangered means facing a very high risk of extinction in the wild. Vulnerable means facing a high risk of extinction in the wild. The U.S. Fish and Wildlife Service lists one species as Threatened, or likely to become endangered in the near future.


Physical characteristics: Oriental helmet gurnards have a long thin body and grow to about 16 inches (40 centimeters) in length. The head is heavily armored. The body is gray to light brown, and there are dark brown and black spots on the back and sides. A long spine just behind the head is followed by a much smaller spine and then two dorsal (DOOR-suhl) fins, which are the fins along the midline of the back. The huge winglike pectoral fins are spotted and have striking blue wavy lines near the edges.

Geographic range: Oriental helmet gurnards live in the Indian Ocean and Red Sea and the Pacific Ocean east to the Hawaiian Islands.

Habitat: Oriental helmet gurnards live on sandy bottoms.

Diet: Oriental helmet gurnards eat bottom-dwelling crustaceans, clams, and fishes.

Behavior and reproduction: Oriental helmet gurnards "walk" along the sea floor stirring up and eating prey. To defend themselves oriental helmet gurnards quickly expand their large winglike pectoral fins. Scientists know little about how oriental flying gurnards reproduce in the wild.

Oriental helmet gurnards and people: Oriental helmet gurnards are caught for the aquarium business.

Conservation status: Oriental helmet gurnards are not threatened or endangered. ∎


Physical characteristics: Red lionfish have dark red bands on the head and body and have pectoral fins that look like long feathers. The dorsal and anal fins are covered with dark rows of spots on a clear to yellowish background. The anal (AY-nuhl) fin is the fin along the midline of the belly. The fin spines are venomous. Red lionfish reach a length of about 14 inches (35 centimeters).

Geographic range: Red lionfish are native to the Indian and Pacific oceans. A small number live in the Atlantic Ocean along the coast of the United States.

Habitat: Red lionfish live on reefs, usually in shallow water.

Diet: Red lionfish are fierce predators (PREH-duh-ters). They hunt other animals for food and feed primarily on small fishes, shrimps, and crabs.

Behavior and reproduction: Red lionfish feed at night and hide among rocks or in caves during the day. They use their fanned-out pectoral fins to trap prey in a corner then suck in the animal whole. Lionfish use their venomous spines for protection. They charge attackers and pierce them with the dorsal spines. After the puncture, glands at the base of the spines shoot venom along the spines and into the attacker. The bright color of the lionfish is a warning for predators to stay away.

Red lionfish usually live alone, but a single male forms groups with females for mating. Females produce two tubes made of mucus and eggs. Soon after release, the egg tubes swell with seawater and are penetrated by the male's sperm. Larvae hatch after thirty-six to forty-eight hours.

Red lionfish and people: Red lionfish are collected for the aquarium business. Even though they are venomous, red lionfish also are caught for food.

Conservation status: Red lionfish are not threatened or endangered. ∎

LINGCOD (Ophiodon elongatus): SPECIES ACCOUNTS

Physical characteristics: Lingcod are large, up to 5 feet (1.5 meters) long and weighing 100 pounds (45 kilograms). The mouth has large teeth. The dorsal fin runs the entire length of the body and looks like two fins. Most lingcod are brown; some are blue-green. They all have staggered black blotches along the sides of the body and the back. Males become all black in the winter just before mating.

Geographic range: Lingcod live in the Pacific Ocean along the west coast of North America from Alaska to Mexico.

Habitat Lingcod spawn, or release eggs, on rocky reefs along the shoreline. After spawning the females move to sand and mud bottoms in deeper water. Males stay on the spawning reefs.

Diet: Lingcod mainly eat fish, including young lingcod, by swallowing them head first.

Behavior and reproduction: Lingcod rest near rocks and wait for prey to come close. Males spawn with one female after another, guarding up to three egg masses at a time.

Lingcod and people: Lingcod is valued as a food fish.

Conservation status: Lingcod are not threatened or endangered. ∎



Allen, Missy, and Michel Peissel. Dangerous Water Creatures. New York: Chelsea House, 1992.

Gilbert, Carter Rowell, and James D. Williams. National Audubon Society Field Guide to Fishes: North America. New York: Knopf, 2002.

Web site:

"Lionfish Invade Eastern US Coast." Neuroscience for Kids. (accessed on November 10, 2004).