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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.
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).
Predation on egg cases is thought to be a major source of mortality for developing oviparous sharks, skates and chimaeras. [16] In general, predation is the leading cause of mortality for marine fish eggs, due to their abundance and high nutritional value. [16]
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".
A bluefin notho killifish, Nothobranchius rachovii, from East Africa A killifish is any of various oviparous (egg-laying) cyprinodontiform fish, [1] including families Aplocheilidae, Cyprinodontidae, Fundulidae, Nothobranchiidae, Profundulidae, Aphaniidae and Valenciidae.
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.
Skates are oviparous, meaning they lay eggs with very little development in the mother. This is one major difference from rays, which are viviparous , meaning they give birth to live young. When a female skate is fertilized, a protected case forms around the embryo called an egg case , or more commonly mermaid's purse.
The eggs of oviparous skates are laid in leathery egg cases that are commonly known as mermaid's purses and which often wash up empty on beaches in areas where skates are common. Capture-induced premature birth and abortion (collectively called capture-induced parturition) occurs frequently in sharks and rays when fished. [ 7 ]