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Enchanted Learning All About Sharks!

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Shark Glossary

SALMON SHARK The Salmon shark (Lamna ditropis, also known as the Pacific Porbeagle) is named for its favorite meal - salmon. This shark is found in the Bering Sea and off western North America. It lives from the surface down to moderate depths. The skin is dusky gray above and paler below with white markings. A strong swimmer, it has a wide tail that has a double keel (a second, short ridge running along the upper part of the lower lobe of the tail). A double keel is unusual among sharks; the only other double-keeled tail is on the closely-related Porbeagle Shark, Lamna nasus.] The largest-known Salmon Shark was 10 ft (3 m) long. Classification: Order Lamniformes (mackerel sharks), Family Lamnidae (Mackerel sharks, porbeagles, and white sharks).

SANDBAR SHARK Carcharhinus plumbeus (also called the Thickskin shark, the brown shark, the northern whaler, and the ground shark) is a common shark with a very tall dorsal fin. They have mouse-gray skin, with paler skin below; the head is wide and flat. They largest found was about 8 ft (2.4 m) long; on average, females are 6 ft (1.8 m) long and males are 3.2 ft (1 m) long. Sandbar sharks are found from very shallow waters to deep waters, generally staying on the bottom. They also frequent estuaries and harbors. Sandbar sharks have a growth rate of about 1.7 inches (43 mm) per year, a slow growth rate for sharks. The thick skin is used for leather. These strong swimmers migrate over 1550 miles (2500 km). Their diet is mostly fish, including menhaden, eels, other sharks, skates, squid, and also crustaceans. Females are mature at 16 years and give birth to 8-12 live young after a gestation period of 9-12 months. Pups are about 8.5 inches (22 cm) long at birth. Classification: Order Carcharhiniformes, Family Carcharhinidae (requiem sharks).

SAND SHARKS Sand sharks (or sandtiger sharks) are bottom-dwelling mackerel sharks (Odontaspididae). They include the Sandtiger shark (Eugomphodus taurus), the Indian sandtiger (Eugomphodus tricuspidatus), the Smalltooth sandtiger (Odontaspis ferox), and the Bigeye sandtiger (Odontaspis noronhai). They live in tropical and temperate coastlines of all the oceans. They all have long, thin, pointed teeth, and eat mostly fish and invertebrates.

SANDTIGER SHARK Sandtigers (Eugomphodus taurus) are also known as the Ragged tooth shark, the grey nurse shark, the sand shark, and the spotted ragged-tooth shark. They are widespread Mackerel sharks (Lamniformes) that range from gray to brown and are about 10-12 feet (3-3.7 m) long. They are fish-eaters that have long, sharp teeth in a narrow snout. They eat and migrate in groups; their activity peaks at night. They are found mostly near coastlines, from the surface down to depths of 3,900 ft (1,200 m). are oviphagous and females have two uterine chambers (wombs). Developing embryos in the wombs are cannibalistic, eating their siblings. Although many embryos are produced, only two are born, one from each uterine chamber. The gestation period is about 8-9 months. Pups are roughly 3.3 feet (1 m) long at birth. Classification: Order Lamniformes (Mackerel sharks), Family Odontaspididae (Sandtiger sharks).

SAWSHARKS Sawsharks are clade of shark that have a long, toothed snout, no anal fin, and the mouth underneath. These common, harmless sharks have a slightly flattened body, nasal barbels, and its pair of five gill slits are on the side of its head. These sharks reproduce via aplacental viviparity. Their diet consists mostly of bony fishes. This order of sharks is called the Pristiophoriformes.

SCALLOPED HAMMERHEAD Scalloped Hammerheads Sphyrna lewini are also known as Kidney-headed sharks. The front of the head of this shark is flattened, scalloped and wide, forming a structure called a cephalofoil. This oddly-shaped head helps the shark swim, making the shark more hydrodynamic. The eyes are at the tip and slightly below the head. The head is also dense with sensory receptors. Scalloped Hammerheads grow to be about 10-13 ft (3-4 m) long. They swim in warm temperate and tropical waters. They eat bony fish, and cephalopods. Pups are born live in litters of 15-30; they are 17-22 inches (43-55 cm) long at birth. Classification: Order Carcharhiniformes

SCHOOL A school is a group of fish that travels together. Some sharks and rays travel in schools.

SCHOOL SHARK Galeorhinus galeus is also known as the Soupfin Shark and Tope. This common shark is gray on top and white underneath; it frequently swims in schools. This harmless shark has a slim body , a small second dorsal fin, and a large top lobe on its tail. The Soupfin shark is up to 6.5 ft (2 m) long and has a life span of over 50 years. It eats squid, octopus, and fish. The Soupfin lives in temperate waters almost worldwide and migrates long distances to cooler water for giving birth. The Soupfin shark reproduces via aplacental viviparity, having litters of up to 52 pups after a gestation period of one year. Pups are about 12-14 inches (30-35 cm) long at birth. Females are mature at 8-10 years and have a low reproductive rate. It is fished for its fins, meat and liver oil. Galeorhinus galeus was named by Linnaeus in 1758. Classification: Order Carcharhiniformes (ground sharks), Family Triakidae (houndsharks, topes, whiskery sharks).

SEAL SHARK The seal shark, Deania licha (also known as the kitefin shark, Bonnaterre's deepwater shark, and the black shark) is a dark, chocolate-colored shark (sometimes with black spots) that lives at the ocean bottom. This sluggish shark has fringed lips and very abrasive skin. It has extremely strong jaws with smooth, thorn-like upper teeth, and wide, serrated, triangular bottom teeth. It hunts bonito. The seal sharks habitat is deep in tropical and warm temperate seas. Females average about 4.5 ft (1.38 m) long; males average about 3.2 ft (1 m) long. The largest-known one was 5.2 ft (1.59 m) long. Classification: Order Squaliformes, Family Squalidae.

SEDIMENTARY ROCK Sedimentary rock is rock that has formed from sediment. Most fossils are found sedimentary rock.

SERRATED Serrated means having a jagged edge that is good for sawing. Serrated teeth are good for cutting through meat. Many sharks have serrated teeth.

SEVENGILL SHARKS The sevengill sharks (the Broadnose sevengill, Notorynchus cepedianus and the Sharpnose sevengill, Heptranchias perlo) are distinctive and rare sharks that have seven gills (most sharks have five). These unusual sharks also have a single (and small) dorsal fin. The broadnose sevengill grows to be up to 10 ft (3 m) long, is speckled and silvery; this shark has small eyes, and a wide head. The sharpnose sevengill is up to about 4.5 ft (1.4 m) long. These aggressive sharks eat fish (including other sharks, rays, and bony fish), seals, and scavenged prey (including human corpses). Broadnose sevengill sharks live in temperate seas on continental shelves (to a depth of 450 ft (135 m). The upper teeth are jagged and multi-cusped (except the center tooth). The lower teeth are comb-shaped. These sharks bear live young in shallow bays. Litters of up to 80 pups have been found. Pups are about 16-18 inches (40-45 cm) long. Classification: Order Hexanchiformes, Family Hexanchidae .

SHARPNOSE SHARK The Atlantic Sharpnose Shark (Rhizoprionodon terraenovae) is a harmless, edible, requiem shark (Family Carcharinidae). The Sharpnose is a small, slender shark with 5 gill slits, two dorsal fins, an anal fin, no fin spines, the mouth behind the eyes, and nictitating eyelids. It has a long, sharp snout, black-edged dorsal and caudal fins (which fade with age), and furrowed or wrinkled corners of the mouth. It is brown to olive-gray colored with white countershading on the belly and is from 2 to 4 feet (60-120 cm) long. A carnivore, it eats small fish, mollusks, and shrimp. The sharpnose is viviparous, with litters of 4 to 7 pups. Classification: Order Carcharhiniformes

SHORTFIN MAKO SHARK The short-finned mako shark (Isurus oxyrincus), also known as the bonito, is the fastest shark. This fish can also leap out of the water. It has has a conical snout, and long gill slits. Short-finned Makos average 5-8 feet (1.5-2.5 m) long but can reach 12 feet (3.7 m) long, weighing 1,000 pounds (455 kg). The Mako is considered dangerous to people. It reproduces via aplacental viviparity and the pups are cannibalistic in the womb. Makos can maintain a body temperature higher than that of the surrounding water. Order: Lamniformes

SHOVELHEAD SHARK Sphyrna tiburo (also known as the bonnethead shark) is a small hammerhead shark with a smooth, rounded head. It has small, sharp teeth in the front of the mouth (for grabbing soft prey) and flat, broad molars in the back (for crushing hard-shelled prey). It is a common, harmless, timid shark averaging about 3.3 feet (1 m) long. It is gray-brown above and lighter on the underside with short pectoral fins Large schools migrate to warm water in the winter and cooler water in the summer. Females are mature at 2.5 feet (75 cm) long and give birth in shallow bays to 8 to 16 pups about 14 inches (35 cm) long. Bonnetheads are found in the western Atlantic and eastern Pacific Oceans, in the surf zone, reefs, on sandy bottoms and in estuaries. Classification: Order Carcharhiniformes, Family Sphyrnidae (hammerhead sharks).

SHOVELNOSE SHARK (1) Carcharhinus leucas is also known as the Bull shark, the Ganges shark, the River shark, the Cub shark, the Zambezi shark, Van Rooyen's shark, the Slipway gray shark, the Square-nose shark, and the Nigaragua shark. It is a large, fierce predator that eats fish, including other sharks, ray, and just about anything else. It has been known to attack people and will venture into fresh water.

SILVERTIP SHARK Silvertip sharks (Carcharhinus albimarginatus) is a large, widespread requiem shark with silvery-white tips on the fins. It grows to be about 10 ft (3 m) long. This common shark lives in coral reefs, offshore islands and lagoons, eating mostly fish. Silvertips are viviparous with a gestation period of about one year. Females usually have 5-6 pups in a litter. Silvertips are attracted to low-frequency sounds. Attacks on people are rare.

SIXGILL SHARKS The sixgill sharks are distinctive sharks that have six gills on each side of the body (most sharks have five). They include the Bluntnose sixgill (Hexanchus griseus), the Bigeye sixgill (Hexanchus vitulus), and the frilled shark (Chlamydoselachus anguineus). These unusual sharks also have a single (and small) dorsal fin near the end of the body. These sharks are gray-brown in color and are paler underneath. The Bluntnose sixgill (also known as the Cow shark, the Grey shark, the mud shark and the Bulldog shark) is a common shark about 16 ft (4.8 m) long with a toxic liver (but edible flesh) and six rows of saw-like teeth in the side of the jaws; it eats large fish, crabs and squid, lives in dark waters at depths down to 5900 ft (1800 m), and has litters of up to 100 pups. The Bigeye sixgill (also known as the lesser sixgill and the calf shark) is about 5.9 ft (1.8 m) long, has large eyes, a slender body, five rows of saw-like teeth in the side of the jaws and lives on or near the bottom of warm temperate and tropical seas. Classification: Order Hexanchiformes, Family Hexanchidae.

SKIN Shark skin is made of a matrix of tiny, hard, tooth-like structures called dermal denticles or placoid scales. These structures are shaped like curved, grooved teeth and make the skin a very tough armor with a texture like sandpaper. They have the same structure as a tooth with an outer layer of enamel, dentine and a central pulp cavity. Unlike the scales of scales of bony fish (ctenoid scales) that get larger as the fish grows, placoid scales stay the same size. As the shark grows, it just grows more placoid scales. These scales also help the shark swim more quickly because their streamlined shapes helps decrease the friction of the water flowing along the shark's body, by channeling it through grooves. Also, the shark's skin is so rough that contact with it can injure prey.

SLEEPER SHARK Somniosus microcephalus, also known as the Greenland shark, and the gurry shark, lives very deep in the North Atlantic Ocean. It lives at depths down to 1,800 feet (550 m) in very cold water (36-45°F=2-7°C). It is up to 21 feet (6.5 m) long. This grayish-brown shark has a short snout and is a slow swimmer. Bioluminescent (glowing) copepods attach to the Greenland shark's eyes attract prey to the shark's head! The shark's upper teeth are long and sharp; the lower teeth are flatter, more closely-set (and also sharp). These sharks gather in large numbers in shallow Arctic waters (up to 80° north) during the winter but migrate back to deep waters during the summer. Eskimo hunters traditionally used its skin for boots and its teeth for knives. This large shark is oviviparous, having litters of about 10 pups, each roughly 15 inches (38 cm) long. Classification: Order Squaliformes, Family Squalidae (dogfish sharks)

SLIPWAY GRAY SHARK Carcharhinus leucas is also known as the Bull shark, the Ganges shark, the River shark, the Cub shark, the Zambezi shark, Van Rooyen's shark, the Shovelnose shark, the Square-nose shark, and the Nigaragua shark. It is a large, fierce predator that eats fish, including other sharks, ray, and just about anything else. It has been known to attack people and will venture into fresh water.

SMALLTOOTH SANDTIGER SHARK The Smalltooth Sandtiger Shark , also known as the Shovelnose Shark(Odontaspis ferox) is a charcoal-colored, bottom-dwelling shark about 9 ft (2.75 m) long. This shark is not known to attack people.

SNOUT The snout is the front part of an animal's face.

SONAR Whales use sonar to sense objects. In sonar (echolocation), a high-pitched sound (usually clicks) is sent out by the whale. The sound bounces off the object and some returns to the whale. The whale interprets this returning echo to determine the object's shape, direction, distance, and texture.

SOUNDING Sounding is when a whale dives deeply to escape danger.

SOUPFIN SHARK Galeorhinus galeus is also known as the School Shark and Tope. This common shark is gray on top and white underneath; it frequently swims in schools. This harmless shark has a slim body , a small second dorsal fin, and a large top lobe on its tail. The Soupfin shark is up to 6.5 ft (2 m) long and has a life span of over 50 years. It eats squid, octopus, and fish. The Soupfin lives in temperate waters almost worldwide and migrates long distances to cooler water for giving birth. The Soupfin shark reproduces via aplacental viviparity, having litters of up to 52 pups after a gestation period of one year. Pups are about 12-14 inches (30-35 cm) long at birth. Females are mature at 8-10 years and have a low reproductive rate. It is fished for its fins, meat and liver oil. Galeorhinus galeus was named by Linnaeus in 1758. Classification: Order Carcharhiniformes (ground sharks), Family Triakidae (houndsharks, topes, whiskery sharks).

SPECIES In classification, a species is a group of closely related organisms that can reproduce. A group of similar species forms a genus. In the scientific name of an organism, the second name is its species (for example, people are Homo sapiens - our species is sapiens).

SPINED PYGMY SHARK Squaliolus laticaudus is one of the smallest sharks; it is roughly 8 to 10 inches (20 to 25 cm) long (females are about 10 inches = 25 cm long; males are up to 9 inches = 23 cm long). This deep water shark has a spine in front of its first dorsal fin but not in front of the second dorsal fin (this is unique among sharks). This harmless shark is very sleek and has a bulbous snout. The upper teeth are narrow and small; the lower teeth and larger and knife-like. It has a large spiracle (an extra, round gill slit) behind each large eye. It is dark-gray to black with white-tipped fins and bio-luminescence (luminous photophores) on its belly; these photophores light up and may serve as camouflage (they eliminate shadows when seen from below). It eats squid, shrimp, and mid-water fish (especially lanternfishes). This uncommon shark lives in deep water (down to 6,550 ft = 2,000 m) but migrates vertically each day to hunt at night in mid-depth waters (about 650 ft = 200 m). It is found in temperate and tropical oceans worldwide. Its reproductive biology is unknown. Classification: Order Squaliformes.

SPINNER SHARK Carcharhinus limbatus (also known as the blacktip shark) is a common shark with black marking on the tips of the dorsal and pectoral fins. It is grayish on top and white underneath, with a white stripe running along the side of the body. It has a very long snout and is about 9 feet ( 2.8 m) long. It is harmless to people (unless provoked or while they are eating). It is found in the western and eastern Atlantic Ocean, and the central, western, and eastern Pacific Ocean. Spinner sharks live at the surface and in shallows, and they migrate along the coasts. Their diet consists mostly of small fish, squid, and crustaceans. They have been seen jumping out of the water during feeding. Females give birth to 4-8 live young (10 inches or 25 cm long) after a gestation period of about 10 to 11 months.

SPINY DOGFISH SHARK Squalus acanthias is the most common shark. These small sharks congregate in schools and migrate. They are about 3-4 feet (0.9-1.2 m) long and are found worldwide.

SPIRACLE The spiracle is a special gill slit found in some sharks. It is located just behind the eyes and supplies oxygen directly to the eyes and brain. Tiger sharks and angelsharks have spiracles.

SPIRAL VALVE The spiral valve is the intestine of some sharks. It looks like a spiral staircase enclosed within a cylinder. This part of the shark's digestive tract enables the shark to efficiently digest its food in a small area, since the surface area of the intestines (where nutrient absorption takes place) is very large within the spiral.

SPOTTED SEVENGILL SHARK The spotted sevengill shark (Notorynchus cepedianus) is a distinctive and rare shark that has seven gills (most sharks have five). This unusual shark also has a single (and small) dorsal fin. The broadnose sevengill grows to be up to 10 ft (3 m) long, is speckled and silvery; this shark has small eyes, and a wide head. These aggressive sharks eat fish (including other sharks, rays, and bony fish), seals, and scavenged prey (including human corpses). Broadnose sevengill sharks live in temperate seas on continental shelves (to a depth of 450 ft (135 m). The upper teeth are jagged and multi-cusped (except the center tooth). The lower teeth are comb-shaped. These sharks bear live young in shallow bays. Litters of up to 80 pups have been found. Pups are about 16-18 inches (40-45 cm) long. It was named by Peron in 1807. Classification: Order Hexanchiformes, Family Hexanchidae. It is also called the ground shark, the cow shark, the broad snout shark and the broadnose sevengill shark.

SPURDOG SHARK Spurdogs are common dogfish sharks that often congregate in large schools. They vary in color, from chocolate-colored to gray, but all are countershaded (having a lighter-colored belly). Most spurdogs are bottom dwellers, living in moderate to deep waters (except the Shortspine and Longnose spurdogs which are also found in very shallow water). Spurdogs have a short snout, a circular body cross-section, have the mouth at the front of the face, and have no anal fin. They bear live young. The Blacktailed spurdog has a dangerous spine on its second dorsal fin. Classification: Order Squaliformes (Dogfish Sharks); Family Squaildae; Genus Squalus; Species asper (the Roughskin spurdog), blainvillei (the Longnose spurdog), melanurus (the Blacktailed spurdog), japonicus (the Japanese spurdog), megalops (the Shortnose spurdog or Spiky Jack), mitsukurii (the Shortspine spurdog), rancureli (the Cyrano spurdog).

SQUALIFORMES A clade of sharks with a short snout, the mouth underneath the snout, and no an anal fin. These include the dogfish and cookiecutter sharks.

SQUARE-NOSE SHARK Carcharhinus leucas is also known as the Bull shark, the Ganges shark, the River shark, the Cub shark, the Zambezi shark, Van Rooyen's shark, the Shovelnose shark, the Slipway gray shark, and the Nigaragua shark. It is a large, fierce predator that eats fish, including other sharks, ray, and just about anything else. It has been known to attack people and will venture into fresh water.

SQUATINIFORMES A clade of sharks with a flat body, the mouth at the front of the head, and no an anal fin. This order include the angelsharks and monkfish.

SQUID Squid are mollusks. They are eaten by many sharks and rays.

STETHACANTHUS Stethacanthus is a genus of strange-looking extinct sharks from the Carboniferous and Permian periods. They had brush-like denticles on the head, a large protrusion on the back, fin spines, an anal fin, and were about 3 feet (1 m) long.

STINGRAY Stingrays are fish with flat bodies, a long tail with at least one spine, and cartilage instead of bones. These rays are closely related to sharks.

SWIM BLADDER The swim bladder is a gas-filled sac in a bony fish's body that gives it buoyancy, allowing it to float. Sharks do not have swim bladder.

SYMBIOSIS Symbiosis is a situation in which two dissimilar organisms live together. There are many types of symbiosis, including mutualism (in which both organisms benefit), commensalism (in which one organism benefits and the other is not affected), or parasitism (in which one organism benefits at the other organism's expense). Symbiosis used to be defined as a situation in which two dissimilar organisms live together to the benefit of both - this is now called mutualism. The word symbiosis means "living together"" in Greek.

SYNAPSID Synapsids include the mammals, and extinct animals such as dimetrodon. They are distinguished by having a skull with a low opening behind their eyes.

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