Class Osteichthyes

ALL Osteichthyes have… Skeleton of bone Gill covering = operculum Swim bladder (helps float) Ex: bony fish

2 SUBCLASSES 1. LOBE-FINNED FISH (7 sp) Fleshy fins supported by bones (limb-like)

COELACANTH - believed to have become extinct w/dinosaurs 65mya (rediscovered 1938 S. Africa) - 1997 2nd sp discovered Indonesia http://www.dinofish.com/

Extinct ones were ancestors to amphibians & all terrestrial verts.

LUNGFISH Modified swim bladder for breathing air Africa, S. Amer., Australia (1 sp ea) Burrow in mud & create mucus lined burrow

To 6 feet

2. RAY-FINNED FISH Majority of bony fishes Very diverse in shape, size, color, feeding, etc.

Classification- Dichotomous Keys Organized set of couplets (2) of exclusive characteristics of biological organisms. Goes from general characteristics to more specific characteristics. Example: 1. a. Does the fish have a snake-like body? If yes, proceed to #2 b. No snake like body? Proceed to #3