Phylum Annelida

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Superclass Osteichthyes bony fishes

• Class Actinopterygii
• Ray finned fishes
• Class Sarcopterygii (lobe fin fishes)
• Lung fishes
• Coelocanth

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Class Actinopterygii
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Class Actinopterygiicharacteristics

• bony dermal scales ganoid, cycloid and ctenoid

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Class Actinopterygiicharacteristics

• paired fins and gills
• well developed skull with 60 bones
• Notochord persists in some absent in others
• Homocercal tail
• bony skeleton
• Operculum covering gills- more effective
  respiration

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Class Actinopterygiicharacteristics

• heart is 2 chambered, 4 pairs of aortic arches
• have a mesonephritic kidney

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Class Actinopterygiicharacteristics

• sexes separate fertilization is usually
  external
• oviparous (lay eggs) most
• some are ovoviviparous (eggs develop in female
  and she gives birth to live young

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Class Actinopterygiicharacteristics

• Osmoregulation
• in freshwater fishes
• the fish is hyperosmotic and
• therefore the kidney is used to get rid of excess
  water

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Class Actinopterygiicharacteristics

• Osmoregulation
• in marine fishes
• the fish is hypoosmotic
• have lower salt content in blood than in sea
  water
• so they tend to gain salt and lose water.

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Class Actinopterygiicharacteristics

• have a swim bladder some have lost it
• swim bladder allows for fishes to maintain
  themselves in water column without expending much
  energy
• a floatation devise
• Swim bladders probably evolved from lungs of
  primitive bony fishes.

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Class Actinopterygiicharacteristics

• Two types of swim bladders
• The swim bladders first were attached to the
  digestive system
• i.e., at the esophagus by a pneumatic duct that
  allowed the bladder to be filled and emptied of
  air.
• In advanced bony fishes this connection is lost
  and the swim bladder is separate from esophagus.
• They have a very specialized gland called the
  rete mirabilis
• which is able to keep the pressure in the
  swimbladder stabiliz

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Class Actinopterygiicharacteristics

• Two types of migration seen in fishes
• Anadromous-
• migrating from salt water to freshwater to
  reproduce
• spend adult life in sea
• ex. salmon (born in freshwater then migrate to
  sea when reach adulthood migrate back to spawning
  grounds)
• Catadromous -
• migrating from freshwater to salt water to
  reproduce
• spend adult life in freshwater
• ex. eels (born in Sargassum Sea migrate to rivers
  in

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Anadromous migratione.g. salmon
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Anadromous migratione.g. salmon
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Catadromous migratione.g. freshwater eel
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Feeding in Fishes

• Carnivorous - prey on large variety of animals
• Herbivorous - eat plants
• Omnivorous - eat both plants and animals
• Filter Feeders - able to filter water of plankton
  and detritus
• Scavengers - feed on decaying plants and animals
• All the above have to do with mouth morphology

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Class Sarcopterygiilobe finned fishes

• Have a fleshy lobe at base of paired fins
• Precursor of appendage to support body
• Diphycercal tail
• Includes
• Lungfishes
• Coelocanth
• Only 7 species exit worldwide