lecture 2 2007 - university of...

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Ichthyology ECOL 482/582

Fish Envy - Is It Wrong?

Anatomy

• External vs. Internal • Hard Anatomy• Soft Anatomy

2

Hard Anatomy - more in lab

External Anatomy

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External Anatomy

(dentary)

Fish Mouth Positions

subterminal

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Fish Mouth Positions

Fins - External AnatomyMedial Fins - Dorsal Fin, Caudal Fin, Anal Fin, Adipose

Lateral fins (paired) - Pelvic Fins, Pectoral Fins

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Internal Anatomy - FinsFin Spines and Rays

Modified Spines

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External AnatomyCaudal and Dorsal Fins

External AnatomyCaudal Fins

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Caudal Fin – Homocercal Tail

External Measurements

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Fish Teeth

Fish Teeth

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Scales – Placoid, Cosmoid, Ganoid, Cycloid,Ctenoid

cosmoidctenoid

cycloid

ganoid

placoid

External AnatomyScales

•Aging scales – Circuli and Annulus

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Internal AnatomyGill Arch – Cover Removed

Internal AnatomyGill Arches

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Fish Skeletons – so many bones, so little time – Axial vs Head

Internal AnatomyAxial Skeleton

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Internal Anatomy – Trunk

Abdominal Vertebrae

Caudal Vertebrae

AXIAL SKELETON

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The head skeleton of a fish = three components, the neurocranium(braincase), suspensorium (jaws plus whatever other structures suspend

them from neurocranium), and branchial skeleton (holds the gills).

Internal AnatomyHead – No neurocranium

SUSPENSORIUMPECTORAL GIRDLE

PELVIC GIRDLE

Branchial(Hyoid)

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Internal Anatomy – Head Amia calva

Internal Anatomy – Head Perca fluviatilis

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Other Characters

• Lateral Line System

• complete v incomplete