Ontology describing the anatomy of Danio rerio from a single cell to adult fish. The namespace of the ontology is zebrafish_anatomical_ontology the prefix is ZFA. Updates to ZFA are released every other month. A subset of the ZFS http://purl.obolibrary.org/obo/zfs.obo is packaged with this ontology.
needs part_of relationships with ventral fin structures. needs def needs develops from ventral fin fold
is this the anal fin?