TERM: Description of glossary term.
protocercal fin
背景: 生理学.
Tail fin that is primitively symmetrical, i.e. vertebrae extend to the tip of the tail.
参考文献
Coad, Brian & D.E. McAllister. 2007. "Dictionary of Ichtyology". Brian W. Coad. Retrieved on June 21, 2014, from:http://www.briancoad.com/Dictionary/Complete%20Dictionary.htm (crc06223)