Ascidiacea (commonly known as the ascidians) is an order in the Urochordata subphylum of sac-like marine filter feeders. They are characterized by a tough outer "tunic" made of the polysaccharide tunicin whilst other tunicates are much less robust. Whilst adults are sessile (immobile), larvae resemble tadpoles and swim up and down in their marine environment. Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria Placozoa Bilateria Acoelomorpha Orthonectida Rhombozoa ? Myxozoa Superphylum Deuterostomia     Chordata (vertebrates, etc. ... Typical Classes Subphylum Urochordata - Tunicates Ascidiacea Thaliacea Larvacea Subphylum Cephalochordata - Lancelets Subphylum Myxini - Hagfishes Subphylum Vertebrata - Vertebrates Petromyzontida - Lampreys Placodermi (extinct) Chondrichthyes - Cartilaginous fishes Acanthodii (extinct) Actinopterygii - Ray-finned fishes Actinistia - Coelacanths Dipnoi - Lungfishes Amphibia - Amphibians Reptilia - Reptiles Aves - Birds Mammalia - Mammals Chordates (phylum Chordata) include the vertebrates, together with... Classes Ascidiacea Thaliacea Appendicularia Urochordata (sometimes known as tunicata and commonly called urochordates, tunicates or sea squirts) is the subphylum of saclike filter feeders with input and output siphons. ... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Classes Ascidiacea Thaliacea Appendicularia Urochordata (sometimes known as tunicata and commonly called urochordates, tunicates or sea squirts) is the subphylum of saclike filter feeders with input and output siphons. ... In biology, a subphylum is a taxonomic grade intermediate between phylum and superclass. ... Filter feeders (also known as suspension feeders) are animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized structure, such as the baleen of baleen whales. ... Polysaccharides (sometimes called glycans) are relatively complex carbohydrates. ... Classes Ascidiacea Thaliacea Appendicularia Urochordata (sometimes known as tunicata and commonly called urochordates, tunicates or sea squirts) is the subphylum of saclike filter feeders with input and output siphons. ... Ten-day-old tadpoles A tadpole (also known as a pollywog) is a larval frog, toad, salamander, or newt. ...

Like other tunicates, they also collect and concentrate vanadium in their blood, although the reason for this behaviour is not properly understood. General Name, Symbol, Number vanadium, V, 23 Chemical series transition metals Group, Period, Block 5 , 4 , d Density, Hardness 6110 kg/m3, 7. ...

Examples of ascidians include Sea Tulips and the Solitary Ascidian. Sea Tulips are sessile ascidians that live in coastal waters at depths of up to 80m (260 ft). ... The Solitary Ascidian is one of the most commonly encountered species of Ascidians. ...

References

• Colin Tudge (2000). The Variety of Life. Oxford University Press. ISBN 0198604262.

Colin Tudge (born 22 April 1943) is a British science writer who is the author of numerous works on agriculture, genetics, and species diversity. ...

External link

• Ascidiacea.com (http://ascidiacea.com/) - Classification and images of many ascidians.