scientific classification

Hawaiian Green Sea Turtle

Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Order: Testudines
Suborder: Cryptodira
Superfamily: Chelonioidea, Bauer, 1893

Genera

Fossil range: Latest Ordovician to Early Permian 
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Class: Acanthodii
Orders: Climatiiformes, Ischnacanthiformes, Acanthodiformes

American Robin

Conservation status Least concern 

Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Turdidae
Genus: Turdus
Species: T. migratorius

Binomial name
Turdus migratorius (Linnaeus, 1766)

Pacific hagfish resting on bottom280 m down off Oregon coast

Scientific classification
Kingdom: Animalia 
Phylum: Chordata 
Subphylum: Vertebrata 
Class: Myxini 
Order: Myxiniformes 
Family: Myxinidae 
Genera: Eptatretus, Myxine, Nemamyxine, Neomyxine, Notomyxine, Paramyxine, Quadratus

A hagfish is a marine chordate of the class Myxini, also known as Hyperotreti. Despite their name, there is some debate about whether they are strictly fish (as there is for lampreys), since they belong to a much more primitive lineage than any other group that is commonly defined fish (Chondrichthyes and Osteichthyes).