Compiler and date details
20 April 2011 - Douglass F. Hoese, Jennifer E. Gates & Dianne J. Bray
This order includes three families and about 100 species of largely freshwater species found worldwide (Nelson 2006 following Johnson & Patterson 1993). All species are characterised by an elongate body with a ventral gill opening. Johnson & Patterson (1993) suggested a relationship with atheriniform, mugiliform and gasterosteiform fishes.
Johnson, G.D. & Patterson, C. 1993. Percomorph phylogeny: a survey of acanthomorphs and a new proposal. Bulletin of Marine Science 52(1): 554-626
Nelson, J.S. 2006. Fishes of the World. Hoboken, New Jersey : John Wiley & Sons, Inc. 601 pp. 
Common Name References
Nelson, J.S. 2006. Fishes of the World. Hoboken, New Jersey : John Wiley & Sons, Inc. 601 pp.  (Swamp Eels)