Scientists aim to describe a single 'tree of life' that reflects the evolutionary relationships of living things. However, evolutionary relationships are a matter of ongoing discovery, and there are different opinions about how living things should be grouped and named. EOL reflects these differences by supporting several different scientific 'classifications'. Some species have been named more than once. Such duplicates are listed under synonyms. EOL also provides support for common names which may vary across regions as well as languages.

Preferred marks the preferred classification for this taxon.

Recognized By Rank Classification
Integrated Taxonomic Information System (ITIS)
view in classification
NCBI Taxonomy
view in classification
Cod Stomach Data, ICES, 1996
  • Tunicata Lamarck, 1816
Encyclopedia of Marine Life of Britain and Ireland Resource Phylum
FALO Classification
view in classification
Subphylum Import
Appeltans et al, 2012
BioImages resource
NatureServe resource Phylum
Paleobiology Database
view in classification
Invertebrates of the Salish Sea Class
SPIRE resource
Sloan-CoML NameLink Project
  • Urochordata
Sloan-CoML NameLink Project
  • Tunicata
World Register of Marine Species (WoRMS)
view in classification
Wikipedia Phylum


EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

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