Glass knifefish

Taxobox
name = Glass knifefishes
fossil_range = Upper Miocene - Recent


image_caption = "Eigenmannia lineata"
regnum = Animalia
phylum = Chordata
classis = Actinopterygii
ordo = Gymnotiformes
subordo = Sternopygoidei
superfamilia = Apteronotoidea
familia = Sternopygidae
subdivision_ranks = Genera
subdivision =
* "Archolaemus"
* "Distocyclus"
* "Eigenmannia"
* "Humboldtichthys" (extinct)
* "Rhabdolichops"
* "Sternopygus"

Glass knifefishes are fishes in the family Sternopygidae in the order Gymnotiformes. Species are also known as rattail knifefishes.cite book | title = Fishes of the World | last = Nelson | first = Joseph, S. | publisher = John Wiley & Sons, Inc. | year = 2006 | id = ISBN 0471250317]

These fishes inhabit freshwater streams and rivers in Panama and South America. Many sternopygid species are specialized for life in the deep (>20 m) swiftly moving waters of large river channels, like that of the Amazon and its major tributares (Crampton et al., 2004) . "Sternopygus" species inhabit both streams and rivers.FishBase family | family = Sternopygidae | year = 2007 | month = Apr]

Many species are highly compressed laterally and translucent in life. These fish have villiform (brush-like) teeth on the upper and lower jaws. The snout is relatively short. The eyes are relatively large, with a diameter equal to or greater than the distance between nares. The anal fin originates at the isthmus (the strip of flesh on the ventral surface between the gill covers). The maximum length is 140 cm in "Sternopygus macrurus".

"Eigenmannia vicentespelea" is the only cave-dwelling gymnotiform. "Humboldtichthys kirschbaumi" (formerly genus "Ellisella") from Upper Miocene of Bolivia is the only fossil gymnotiform.

These fish have a tone-like electric organ discharge (EOD) that occurs monophasically.

Some of these species are aquarium fishes.

References

*Albert, J.S. 2003. Family Sternopygidae. Pp 493-497 in R.E. Reis, S.O. Kullander & C.J. Ferraris, Jr. (eds). Checklist of the Freshwater Fishes of South and Central America. Edipucrs, Porto Alegre, 735p.
*Crampton, W.G.R., K. Hulen, and J.S. Albert. 2004. Sternopygus branco, a new species of Neotropical electric fish (Gymnotiformes: Sternopygidae) from the lowland Amazon basin, with descriptions of ecology and electric organ discharges. Copeia, 2004(2): 244-258.