ural vertebra ural vertebra 1 Ural vertebra that is located directly posterior to preural centrum 1. It may bear a rudimentary neural arch and sometimes a rudimentary spine or the neural arch and spine are completely absent and it may articulate or fuse with hypural 1 (polyural terminology). Ural vertebra 1 is an unpaired median bone. This class was sourced from an external ontology (teleost_anatomy). Its definitions, naming conventions and relationships may need to be checked for compatibility with uberon UBERON:2002163 Ural vertebrae 1 may be defined also as the first ural vertebrae bearing hypurals 1 and 2 (diural terminology).