Domain: Eukarya

Has true nucleus and membrane-bound organelles

Kingdom: Animalia

Heterotrophic, multicellular, motile

Phylum: Chordata

Has a notochord, post-anal tail sometime during development, dorsal nerve cord, pharyngeal slits, and an endostyle.

Class: Actinopterygii

Possess a lepidotrichia or "fin rays," webs of skin supported by bony or horny spines.

Order: Lepisosteiformes

To be a Gar; live in eastern United States, elongated jaw with needlelike teeth, heavy armor scales, vascularized swim bladder.

Family: Lepisosteidae

Same as Lepisosteiformes.

Genus: Lepisosteus

Same as Lepisosteiformes.

Species: Lepisosteus osseus

Lepisosteus is Greek for bony scales; osseus is Latin for bone.

Cladistic phylogenetic tree of the supergroups in the Eukarya domain.

Cladistic phylogenetic tree on the class Actinopterygii.  Meaning all genuses are related by the class Actinopterygii.