Notes:Bony FishNotes:Bony Fish

Class: OsteichthyesClass: Osteichthyes23,000 species23,000 species

Basic FactsBasic Facts• Have a Have a swim bladderswim bladder which can be inflated which can be inflated

or deflated to change position in the or deflated to change position in the water.water.

• They have a terminal mouth.They have a terminal mouth.• The gills are covered by an The gills are covered by an operculumoperculum (gill (gill

covering).covering).• Oviparous, external fertilization.Oviparous, external fertilization.

Oxygen exchangeOxygen exchange

Body ShapeBody Shape • the body plan of a fish the body plan of a fish

directly relates to its directly relates to its lifestyle.lifestyle.

1. 1. StreamlinedStreamlined – fast – fast swimmersswimmers

2. 2. Laterally flattenedLaterally flattened – – bottom dwellerbottom dweller

Tuna

Flounder

Body Shape, cont’dBody Shape, cont’d3. 3. Eel-like bodiesEel-like bodies-live -live

among rocks or among rocks or vegetationvegetation

4. 4. Vertical plane fishVertical plane fish – sea – sea horse (slow swimming)horse (slow swimming)

Morea eel

Yellow Sea horse

ColorationColoration • colored pigments are colored pigments are

found in special cells found in special cells calledcalled chromatophoreschromatophores..

1. 1. Warning colorationWarning coloration – – using color to advertise using color to advertise that you are dangerous. that you are dangerous. (lionfish spines )(lionfish spines )

2. 2. Cryptic colorationCryptic coloration – – blending with the blending with the environment to deceive environment to deceive predators. (Rockfish)predators. (Rockfish)

Coloration, cont’d.Coloration, cont’d.3. 3. Disruptive Disruptive

colorationcoloration – the – the presence of color, presence of color, stripes, bars or spots stripes, bars or spots to break up the outline to break up the outline of a fish.of a fish.

4. 4. CountershadingCountershading – – light on the light on the bottom/dark on topbottom/dark on top