The butterfly rays are a group of rays forming the genus Gymnura and the family Gymnuridae. They are found in warm oceans worldwide, and occasionally in estuaries.
The body of butterfly rays is flattened and surrounded by an extremely broad disc formed by the pectoral fins, which merge in front of the head. They have a very short, thread-like, tail. They range from 31Â cm (12Â in) to 4Â m (13Â ft) in body length.
McEachran et al. place the butterfly rays in the subfamily Gymnurinae of the family Dasyatidae, but this article follows FishBase and ITIS in treating them as a family.
- Gymnura afuerae (Hildebrand, 1946)  <li>Gymnura altavela (Linnaeus, 1758) â" Spiny butterfly ray 
- Gymnura australis (E. P. Ramsay & Ogilby, 1886) â" Australian butterfly ray 
- Gymnura bimaculata (Norman, 1925) â" Twin-spot butterfly ray 
- Gymnura crebripunctata (W. K. H. Peters, 1869) â" Longsnout butterfly ray 
- Gymnura crooki Fowler, 1934 
- Gymnura hirundo (R. T. Lowe, 1843) â" Madeira butterfly ray 
- Gymnura japonica (Temminck & Schlegel, 1850) â" Japanese butterfly ray 
- Gymnura marmorata (J. G. Cooper, 1864) â" California butterfly ray 
- Gymnura micrura (Bloch & J. G. Schneider, 1801) â" Smooth butterfly ray 
- Gymnura natalensis (Gilchrist & W. W. Thompson, 1911) â" Backwater butterfly ray 
- Gymnura poecilura (G. Shaw, 1804) â" Longtail butterfly ray 
- Gymnura tentaculata J. P. MÃ¼ller & Henle, 1841 â" Tentacled butterfly ray 
- Gymnura zonura Bleeker, 1852 â" Zonetail butterfly ray