Livebearers belong to the massive order, Cyprindontiformes and are made up of, among others,
the families Anablepidae, Goodeidae, Hemirhamphidae, and Poeciliidae. Livebearers are the most popular of
all aquarium species due to the wide availability, relatively peaceful behavior, and their colors. Livebearers
have a wide range of appearance, from the common guppy to the odd Freshwater Sting Ray (Potamotrygon sp.). Livebearers are distributed
throughout Southeast Asia, the Americas, and the Caribbean. The eggs are fertilized internally in the female. The eggs are fertilized by the male
through a mating organ, usually a modified anal fin.
The embryos develop in one of two ways depending on the fish:
(1) In ovovivoparous species, the young develop inside eggs within the mother's body. The
nourishment is provided by the yolk of the egg.
The young hatch inside the mother's body and pass out through the anus.
(2) In viviparous species,
the young develop without egg inside of the mother's body. The young are nourished by secretions of the
female or through an umbilical-like cord.
Shark-repelling fishing gear in the works
(4/23/2008) Fishing gear that produces an electric field in sea water could help prevent sharks from becoming accidental bycatch, say scientists at NOAA.
Feds flood the Grand Canyon to save endangered fish
(3/5/2008) Federal government officials unleashed a flood of water from Glen Canyon Dam in northern Arizona to help restore the Grand Canyon's ecosystem which has suffered as a result of changes caused by the dam.
The copy for fish.mongabay.com was written in 1994-1995. Therefore some information such as scientific names may be out of date. For this, I apologize. Feel free to send corrections to me.
