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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.
In oviparous fish, internal fertilisation requires the male to use some sort of intromittent organ to deliver sperm into the genital opening of the female. 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.
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 ).
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).
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]
The longest fish recorded was 25.17 inches (63.9 cm) long, and may weigh up to 4 pounds (1.8 kg). [5] Because of its long body and sharp teeth, the California lizardfish is occasionally mistaken for the barracuda. The barracuda, however, is silvery rather than brown and has two similar-sized dorsal fins with a wide space between them, whereas ...
Most Amphibians are oviparous and lay their eggs in water, though some have adapted to lay them on land. [7] There are also some species that are viviparous, giving birth to live young. [ 8 ] Eggs can be fertilized either internally or externally depending on the species. [ 7 ]
Actinopterygii (/ ˌ æ k t ɪ n ɒ p t ə ˈ r ɪ dʒ i aɪ /; from Ancient Greek ἀκτίς (aktis) 'having rays' and πτέρυξ (ptérux) 'wing, fins'), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish [2] that comprise over 50% of living vertebrate species. [3]