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Oviparous fish are fish that reproduce by spawning fertilized eggs outside of the body that grow into hatchlings.This process is unlike live-bearing viviparous species, which develop and nourish embryos and inside the womb, or live-beaering ovovivipary species, which develop and nourish eggs with egg yolk.
Among mammals, monotremes (four species of echidna, and the platypus) are uniquely oviparous. In all but special cases of both ovuliparity and oviparity, the overwhelming source of nourishment for the embryo is the nutrients stored in the yolk, pre-deposited in the egg by the reproductive system of the mother (the vitellogenesis ).
Examples include the oviparous sharks, such as the horn shark, and oviparous rays, such as skates. In these cases, the male is equipped with a pair of modified pelvic fins known as claspers. Marine fish can produce high numbers of eggs which are often released into the open water column. The eggs have an average diameter of 1 millimetre (0.039 in).
Zenarchopteridae, the viviparous halfbeaks, is a family of ray-finned fishes in the order Beloniformes.The Zenarchopteridae exhibit strong sexual dimorphism, practicing internal fertilisation, and in some cases ovoviviparous or viviparous (the family also includes oviparous species).
They are generally social creatures and travel in schools of 40 fish. If the dominant male dies in the pack, one of the females will change gender and color and become the alpha male
Among mammals, the monotremes are oviparous. Ovo-viviparity: or oviparity with retention of zygotes in either the female's or in the male's body, but there are no trophic interactions between zygote and parents. [1] This mode is found in the slowworm, Anguis fragilis. In the sea horse, zygotes are retained in the male's ventral "marsupium".
Ovoviviparous fish give birth to live young. Unlike viviparous species, their embryos are nourished by an egg yolk, and not directly by the parent.. See also:Category:Viviparous fish - fish which give birth to live young which receive nourishment whilst in the womb.
Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a term used as a "bridging" form of reproduction between egg-laying oviparous and live-bearing viviparous reproduction. Ovoviviparous animals possess embryos that develop inside eggs that remain in the mother's body until they are ready to hatch.