chrondrichthyes or cartilaginous fishes are jawed fish with paired fins, paired nares, scales, two-chambered hearts, and skeletons made of cartilage rather than bone.
chrondrichthyes are also known as cartilaginous fish with paired nares n fins.
Chondroichthyes is the phylum name for the cartilaginous fishes. It includes sharks, skates, and rays.
Chrondrichthyes have tooth like scales called denticles or placoid scales. Denticles provide two functions, protection, and in most cases streamlining. Mucous glands exist in some species as well.
Crayfish and shrimp (Arthropods), Dolphins (Cetaceans), Eels (Anguilliformes), Fish (Agnatha, Chrondrichthyes, and Osteichthyes), Fly larvae (Insects/Arthropods), Hydroids (Actiniaria), Snails (Mollusks), Water mites (Arachnids/Arthropods), Worms (Oligochaetes), Worms (Nemetodes).
Kingdom: AnimaliaPhylum: ChordataSub-Phylum: Vertebrata (vertebrates)Class: Chrondrichthyes (cartilaginous fish)Sub-Class: Elasmobranchii (sharks and rays)Order: LamniformesFamily: LamnidaeGenus: CarchardonSpecies: C. carcharias
Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Then there are three other classes they can be in. Agnatha: Jawless fish, such as a lamprey Chrondrichthyes: Fish whose skeletons are made of cartilage, such as a shark Osteichthyes: Fish whose skeleton is composed of bone, like bass. Osteichthyes' two sub classes are Ray-finned: like a catfish Lobe-finned: like a lungfish
I think, starting with the kingdom and working through, it would be 'Animalia' (animals), then 'Chordata' (animals with backbones), then 'vertebrata' and finally 'fish'. So... well, I think fish are, fish. They're aquatic vertebrates.
They are: Mammalia, Reptilia, Aves, Osteichthyes, Chrondrichthyes, Agnatha, Amphibia. They are the main 7, but there should actually be more go to: http://en.wikipedia.org/wiki/List_of_chordate_orders for more details.