Chordata (45,000 Species)

Chordate characteristics

-Bilaterally symmetrical

-Deuterostomates

-At one point in their lives they have each of these 4 things

-Notochord

-Pharyngeal slits

-Dorsal tubular nerve cord

-Postanal tail

-Presence of endostyle or thyroid gland

-Complete digestive tract

-Ventral, contractile blood vessel (heart)

Vertebrates

Three classes of Fish

Class Agnatha

-Hagfish (30 species)

-Lampreys (35 species)

Class Chondrichthyes (Sharks, rays, chimaeras) (1,000 species)

Class Osteichthes

The Boney Fish (27,000 species)

Clade Tetrapods (29,000 species)

Class Amphibians

-Order Caecilians (No legs)

-Order Caudata (Salamanders) (retain their tail as adults)

-Order Anura (Frogs) (lack tails as adults)

-Toads- terrestrial frog

Clade Amniotes (have amniotic eggs)

Class Reptiles

-Order Crocodilians (23 species)

-Order Testudines (Turtles) (307 species)

-Tortoise- terrestrial turtle

-Order Sphenodontida (Tuataras) (2 species)

-Order Squamates (Snakes and lizards) (7,910 species)

Class Aves /Birds (10,000 species)

Class Mammals

-Order Monotremes (Lay eggs) (5 species)

-Infra-Class Marsupials (Mammals with a pouch) (324 species)

-Clade Eutherians (Placental mammals) (5,010 species)