Scientific Classification Characteristics
Kingdom Animalia Animals are Eukaryotic and multicellular which separates them form bacteria and protists.  They are heterotrophic which sets them apart from the plants and algae.  They also lack a cell wall which separates them from the plants and fungi.  They are motile. The characteristic that is exclusive though is that the embryos pass through a blastula stage.
Phylum Nematoda The "roundworms" Nematodes are classified under this because they have a unique digestive system which is like a tube with openings on both ends.  This characteristic is what separates them from the cnidarians and the Platyhelminthes 
Class Nematoda  
Order Ascaridia This order contains a few families of parasitic roundworms which have three "lips' on the anterior end.  They were also further separated because of DNA sequencing.  
Family Ascarididae This family is composed of large parasitic roundworms which are intestinal parasites that infect all classes of vertebrates. 
Genus Baylisascaris This genus of parasitic roundworms infect more then 50 different animal species.  They are classified here because they spread them selves via depositing their eggs in the fecal matter of the animal in which they infest.
Species B. procyonis This specific species is classified here because its definitive host for reproduction is the raccoon.