Cyprinidae: Arnoldichthys Spilopterus Astyanax

Saturday, 21 July 2012

Arnoldichthys Spilopterus Astyanax

Characidae is a large and diverse family of freshwater subtropical and tropical fish, with members found in Central and South America, southern North America, and Africa, and include such varied forms as the piranhas, the tetras, a blind cavefish in Mexico (populations of Astyanax mexicanus found in caves) and Brazil (Stygichthys typhlops), and a species found as far northward as southwestern United States (Astyanax mexicanus) (Nelson 1994). The characins are distinguished from other fish by the presence of a small adipose fin between the dorsal fin and caudal fin. Both the Characidae family and the Alestiidae families are comprised only of freshwater fish.

The South American tetras, placed in the subfamily Tetragonopterinae within Characidae, comprise numerous genera, including Hemigrammus, Hyphessobrycon, Paracheirodon (the neon, green, and cardinal tetras), and Tetragonopterus.