Fishes - Overview

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• Fishes - Overview
• Chondrichthyes (Cartilaginous fishes)
• Rays and Skates
• Body dorsoventrally flattened
• Often live on/near bottom (demersal)
• Gill slits (five pairs) on ventral surface
• Pectoral fins flat and greatly expanded, often
  fused with head
• Stingrays
• Whip like tail with hollow spine (poisonous) at
  base
• Eat small animals, including mollusks,
  crustaceans and fishes
• Electric rays
• Stun prey and defend against predators
• Swimming rays
• Eagle, manta rays
• Skates
• No whip-like tail
• No stinging spines
• Lay egg cases (rays bear live young)

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Fig. 8.7
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• Fishes - Overview
• Chondrichthyes (Cartilaginous fishes)
• Ratfishes
• Most common in deep water
• Single pair of gill slits
• Feed on benthic crustaceans and mollusks

Fig. 8.7
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• Fishes - Overview
• Osteichthyes (Bony fishes)
• About 26,000 species
• Skeleton made of bone
• Cycloid (round, smooth) or ctenoid (spiny) scales
  made of bone
• Thin, flexible, overlap
• Bony operculum covers gill chamber on each side
• Caudal fin usually homocercal (vs. heterocercal
  in sharks)
• Fins composed of fin rays connected by thin
  membranes
• Mouth typically terminal
• Jaws have more freedom of movement than in sharks
• Swim bladder to regulate buoyancy
• Helps to compensate for dense bony skeleton

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Fig. 8.8
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• Fishes - Biology
• Body Shape
• Strongly related to lifestyle
• Fusiform, streamlined
• Sustained high speed (up to 50 mph)
• Ex Tunas, mackerels, marlins
• Laterally compressed
• Slow cruising, occasional burst swimming
• Ex Snappers, wrasses, butterflyfishes
• Flattened
• Sedentary, often demersal
• Ex Flatfishes (flounders, halibuts, soles), sea
  robins
• Elongate, eel-like
• Cryptic, living in tunnels, crevices
• Ex Moray eels, pipefishes, trumpetfishes
• Unusual, irregular
• Often with camouflage color/pattern
• Ex Sargassum fishes, seahorses, trunkfishes,
  stonefishes

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Fig. 8.9
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• Fishes - Biology
• Body Shape
• Strongly related to lifestyle
• Fusiform, streamlined
• Sustained high speed (up to 50 mph)
• Ex Tunas, mackerels, marlins
• Laterally compressed
• Slow cruising, occasional burst swimming
• Ex Snappers, wrasses, butterflyfishes
• Flattened
• Sedentary, often demersal
• Ex Flatfishes (flounders, halibuts, soles), sea
  robins
• Elongate, eel-like
• Cryptic, living in tunnels, crevices
• Ex Moray eels, pipefishes, trumpetfishes
• Unusual, irregular
• Often with camouflage color/pattern
• Ex Sargassum fishes, seahorses, trunkfishes,
  stonefishes

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Fusiform
Video
Ch. 15, p. 326
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• Fishes - Biology
• Body Shape
• Strongly related to lifestyle
• Fusiform, streamlined
• Sustained high speed (up to 50 mph)
• Ex Tunas, mackerels, marlins
• Laterally compressed
• Slow cruising, occasional burst swimming
• Ex Snappers, wrasses, butterflyfishes
• Flattened
• Sedentary, often demersal
• Ex Flatfishes (flounders, halibuts, soles), sea
  robins
• Elongate, eel-like
• Cryptic, living in tunnels, crevices
• Ex Moray eels, pipefishes, trumpetfishes
• Unusual, irregular
• Often with camouflage color/pattern
• Ex Sargassum fishes, seahorses, trunkfishes,
  stonefishes

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Laterally Compressed
Video
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• Fishes - Biology
• Body Shape
• Strongly related to lifestyle
• Fusiform, streamlined
• Sustained high speed (up to 50 mph)
• Ex Tunas, mackerels, marlins
• Laterally compressed
• Slow cruising, occasional burst swimming
• Ex Snappers, wrasses, butterflyfishes
• Flattened
• Sedentary, often demersal
• Ex Flatfishes (flounders, halibuts, soles), sea
  robins
• Elongate, eel-like
• Cryptic, living in tunnels, crevices
• Ex Moray eels, pipefishes, trumpetfishes
• Unusual, irregular
• Often with camouflage color/pattern
• Ex Sargassum fishes, seahorses, trunkfishes,
  stonefishes

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Flattened
Hilburt
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• Fishes - Biology
• Body Shape
• Strongly related to lifestyle
• Fusiform, streamlined
• Sustained high speed (up to 50 mph)
• Ex Tunas, mackerels, marlins
• Laterally compressed
• Slow cruising, occasional burst swimming
• Ex Snappers, wrasses, butterflyfishes
• Flattened
• Sedentary, often demersal
• Ex Flatfishes (flounders, halibuts, soles), sea
  robins
• Elongate, eel-like
• Cryptic, living in tunnels, crevices
• Ex Moray eels, pipefishes, trumpetfishes
• Unusual, irregular
• Often with camouflage color/pattern
• Ex Sargassum fishes, seahorses, trunkfishes,
  stonefishes

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Elongate
Video
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• Fishes - Biology
• Body Shape
• Strongly related to lifestyle
• Fusiform, streamlined
• Sustained high speed (up to 50 mph)
• Ex Tunas, mackerels, marlins
• Laterally compressed
• Slow cruising, occasional burst swimming
• Ex Snappers, wrasses, butterflyfishes
• Flattened
• Sedentary, often demersal
• Ex Flatfishes (flounders, halibuts, soles), sea
  robins
• Elongate, eel-like
• Cryptic, living in tunnels, crevices
• Ex Moray eels, pipefishes, trumpetfishes
• Unusual, irregular
• Often with camouflage color/pattern
• Ex Sargassum fishes, seahorses, trunkfishes,
  stonefishes

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Irregular
Video