General Classification Spiny-rayed fish Hard, sometimes sharp spines in dorsal fin Ex. Yellow Perch

General Classification Soft-rayed fish Dorsal fin is without hard spines Usually have only 1 dorsal fin Adipose fin: small, fatty fin near caudal fin Ex. Trout

Fish Adaptations: Scales Hard, sometimes colorful, overlapping

plates Provides protection from predators and

disease/ infection

4 Types of Scales 1. Placoid: rectangular base, under the

skin, spines project to the surface of the skin

New scales are added, do not grow with the fish

Examples: sharks, skates, rays

Shark: Placoid Scales

Skate: Placoid Scales

Ray: Placoid Scales

4 Types of Scales 2. Ganoid: rhombus shape, connected by

peg and socket joints Do not grow with fish, new ones are added Examples: Gar, Paddlefish, Sturgeon

Longnose Gar: Ganoid Scales

Gar

Sturgeon: Ganoid Scales

Paddlefish: Ganoid Scales

4 Types of Scales 3. Ctenoid: overlapping, allow great

maneuverability as fish bends Grows with fish, found in spiny rayed fish

Ctenoid Scales

4 Types of Scales 4. Cycloid: same as ctenoid functions Smooth margin, soft-rayed fish Grows with fish

Cycloid Scales: Catfish

REVIEWComplete back of note sheetGive different fish examples for

the top 2

2 minutes!!!! GO!!!