Ovoviviparous
Ovoviviparous animals produce eggs inside their body, but then give birth to live young. The eggs hatch out inside the mother and the offspring stay within her for a time. She later gives birth to the them. While they are within her, the young are fed on the yolk of the egg, and not directly from the mother's body. Ovoviviparity is a special type of viviparity. Some fish, amphibians and reptiles reproduce this way, for instance the sand tiger shark.
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Yellow anaconda About
Ovoviviparity (spelling), ovovivipary, or ovivipary, is a mode of reproduction in animals in which embryos develop inside eggs that are retained within the mother's body until they are ready to hatch. Ovoviviparous animals are similar to viviparous species in that there is internal fertilization and the young are born live, but differ in that there is no placental connection and the unborn young are nourished by egg yolk. However, the mother's body does provide gas exchange (respiration).
Ovoviviparity is employed by many aquatic life forms such as fish and some sharks, reptiles, and invertebrates. The young of ovoviviparous amphibians are sometimes born as larvae, and undergo metamorphosis outside the body of the mother.
In sharks and rays, the term ovoviviparity has recently been deprecated in favor of aplacental viviparity. Authors may regard the two terms as synonymous, or equate ovoviviparity only with aplacental yolk-sac viviparity, in which the embryos are solely sustained by yolk (as opposed to secondary provisioning by their mother in the form of "uterine milk", such as in the stingrays, or unfertilized eggs, such as in the mackerel sharks).
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