Author: Jan Scholten
Zoology: pisces are the fishes.
Chordates: cephalochordata, tunicata, and vertebrata; = having a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail for at least some period of their life cycles; 75000 living species
Tunicata: salps and sea squirts.
Hemichordata: including the acorn worms has been presented as a fourth chordate subphylum, but it now is usually treated as a separate phylum.
Echinodermata: starfish, sea urchins, sea cucumbers.
Craniata: vertebrata; vertebrata and hagfish
Vertebrata: fish, amphibians, reptiles, birds, mammals; = with vertebral comumn, backbone.
Class Agnatha (jawless fishes)
Class Chondrichthyes (cartilaginous fishes)
Class Osteichthyes (bony fishes)
Class Amphibia (amphibians)
Class Reptilia (reptiles)
Class Aves (birds)
Class Mammalia (mammals)
Synapsids: means fused arch; is theropsids, meaning beast-face; mammals and related animals; temporal fenestra, an opening low in the skull roof behind each eye, leaving a bony arch beneath each; this accounts for their name. are usually called
Pelycosaurs: primitive synapsids; mammal-like reptiles; stem mammals.
Therapsids: advanced mammals.
Tetrapods: Amphibia and Amniota; four-limbed animals with backbones or spinal columns.
Amphibia: no amnion.
Amniotes: sauropsida and synapsida; tetrapods; egg equipped with an amnion, which is an adaptation to land.
Sauropsida: reptilia and aves; sauropsids: reptiles and birds.
Eutherian mammals (such as humans), these membranes include the amniotic sac that surrounds the fetus. These embryonic membranes, and the lack of a larval stage, distinguish amniotes from tetrapod amphibians..