The animals Oviviviparous , In biology and zoology, are all those kinds of animals that reproduce with means that are common for both the oviparous species and the viviparous species.
In the first group, composed mostly of fish, amphibians, reptiles and birds, the reproduction of living beings is done by eggs that are laid by the female. In the second group, where mammals predominate, reproduction occurs as soon as the female stops her offspring.
Ovoviviparous species, on the other hand, are always characterized by combining both breeding strategies. Ovoviviparism implies that the embryo develops and nourishes itself inside an egg that in turn is inside the body of the mother.
This means that this egg is not placed like a oviparous, but remains in the female until the baby is completely formed and then leaves it to the way the viviparous are born, that is through delivery itself .
In this way there are small but substantial differences between ovoviviparous, viviparous and oviparous. While it is the latter reproduction is with eggs in which the embryo gets its nutrients, the viviparous grow in the placenta of the females and these stop them and then give them sustenance with their mammary glands.
Ovoviviparous, on the other hand, have embryos that feed on the vellum that is inside the eggs until they are born.
20 most known ovoviviparous animals
Ovoviviparous are, in general, animals that are difficult to find in nature, although they predominate among some species of insects, molluscs and annelids, although several of the most common cases are among reptiles (as with The vipers, from which live offspring) and many varieties of fish.
The following list is but a small sample of those representatives of the animal kingdom that are among the ovoviviparous.
1- Shark
There are several species of sharks in which the embryo is nourished from the egg yolk until it becomes a copy identical to the adult.
This means of reproduction, however, gives rise to a small number of offspring, although this is of course compensated by a high rate of survival because the mere fact of having remained within the maternal body protects them from any harm Throughout the course of its development.
The shark - for example the white shark ( Carcharodon carcharias ) - is in fact the most representative example of the ovoviviparous. The reproductive success of this animal, therefore, should not only be due to the fact that it is a natural predator in the waters of the sea, but that its reproductive strategy makes the offspring free of predators that can eat the eggs (as would happen with the Oviparous), and this gives them a special advantage in increasing their numbers in the ocean.
2- Buffer viper
The buzzing snake ( Bitis arietans ) Has a sexual maturity of about 2 years, after which it can be reproduced between the months of October and December. Once the female is fertilized, the incubation of the offspring lasts 5 months. Afterwards, the litter, which consists of up to 30-80 young, are about 20 centimeters long and soon hunt all kinds of prey ranging from amphibians to rodents of various sizes.
3- Anaconda
The anaconda (of the genus Eunectes ) Is par excellence one of the most known snakes in the world. Not in vain is a heavy specimen, of solitary habits to attract their partner, in the case of females, which get mated in the rainy season.
Their hatchlings, which can add up to 40 per litter, are 60 centimeters in length and can hunt prey and swim only a few hours after birth.
4- Lucion
The lution ( Anguis fragilis ) Is known as the lizard without legs; For that reason it is easy that this reptile is taken as a snake both in appearance and in its mode of displacement.
The mating of this animal, which takes place between the months of April and May, causes the female to be pregnant and that adapts to the climate to make her offspring be born as soon as possible; In which these are born (the litter reaches 12) have immediate independence to feed.
5- Limnonectes larvaepartus
He Limnonectes larvaepartus Is one of the most numerous cases of ovoviviparous amphibians, since almost all the members of this category of animals are integrated by oviparous.
That is, while amphibians (i.e., frogs, toads) often lay eggs from which tadpoles develop later, the Limnonectes larvaepartus Has the particularity of giving birth to their young. On average, females produce up to 100 eggs during their breeding season.
6- Staining
The shedding ( Scincidae ) Is a fairly common lizard. The biological variety of these reptiles is as vast as diverse in terms of reproduction. However, it should be noted that not all animals in this family are ovoviviparous, since some are oviparous.
Her eating habit is herbivorous and the female stops up to a maximum of two young that may have a size that is equivalent to one-third of the adult sibling.
7- Good constrictor
The boa constrictor is an ovoviví snake whose sexual maturity is reached after about 2 or 3 years. Their mating is in the rainy season and, after the development of the young, they are lighted by the female; The gestation of it can last for months.
The offspring, in fact, can measure up to 50 centimeters in length (equivalent to about 20 inches), but do not start feeding until two weeks from birth.
8- Garter Snake
The garter snake ( Thamnophis sirtalis ) Is also called a striped snake. After sexual maturity (which can take 2 to 3 years), their mating occurs in the spring season, after the hibernation of this reptile.
Subsequently, the female is fertilized and the eggs are kept in her body for three months until they hatch; From there they leave up to 70 pups per litter that at birth are removed from all maternal care.
9- Mapanare
La mapanare ( Bothrops atrox ) Is the most dangerous snake in South America and it is much seen in the savannas of Venezuela. Its gestation lasts between 3 and 4 months, although its mating can occur during the course of the year.
The pups that are born are up to 30 centimeters in length and their number can reach 70 per litter. Mapanare is a specialist in climbing trees, but also in camouflage on the ground, which is why it is often difficult to see with the naked eye.
10- Iguana
In fact it is a few species of iguanas that are ovoviviparous, although their number is reduced because the vast majority of these reptiles are strictly oviparous. Many of them live in South America and adapt well to the more arid environments.
Their diet is herbivorous but there are also species that can feed on small insects like crickets. Their behavior in the face of threats (predators, for example) is usually to undertake the flight.
11- Phallichthys
He Phallichthys Is a pecílido of which four species are known ( Phallichthys amates, Phallichthys fairweatheri , Phallichthys quadripunctatus Y Phallichthys tico ) Whose females are larger than males.
This genus of ovoviviparous aquatic vertebrate lives in Central America, but is found in Costa Rica, Mexico and Guatemala. Its favorite habitat is fresh water, that is, rivers, streams where there is abundant vegetation.
12- Gabon Viper
The Gabon Viper ( Bitis gabonica ) Is a snake that inhabits sub-Saharan Africa, specifically in countries like Gabon, Ghana, Nigeria and Congo, among others. Its habitat is focused on rainforests, low altitude areas and places with abundant wood.
Their habits are nocturnal and the males tend to be aggressive when they seek to mate with the females. This viper, by the way, is very poisonous and represents a greater danger in agricultural areas.
13- Pez million
To the fish million Poecilia reticulata ) Is also known as guppy or lebistes. It is one of the most abundant tropical fish and is also one of the most sought after in aquariums for its rainbow colors.
This ovoviviparous is located on the Caribbean coasts of Venezuela, Antigua and Barbuda, Trinidad and Tobago, Jamaica, Guyana, Brazil and the Netherlands Antilles. As in other pecílidos, the females of the guppy have a bigger size than the males.
14- Girardinus
Of the Girardinus Is known to be a pecílide belonging to the order of the Cyprinodontiformes . This ovovivíparo lives in the sweet waters of Cuba, reason why it is a fluvial animal of tropical climate with temperatures that go from 22º to 25ºC.
It has no migratory habits. Females, which are up to 9.3 centimeters long, are often larger than males, which reach 3.3 centimeters in length. So far 7 species are known, including Girardinus mettallicus .
15- Phalloceros
The Phalloceros is a fish that inhabits several zones of Argentina, Brazil and Uruguay, hence it receives the common name of guarú-guarú, madrecita, mother of a spot, pikí and barigudinho.
This ovoviviparous aquatic vertebrate is freshwater (ie, a freshwater fish). The measurements of their specimens are different between the sexes, and females (measuring up to 6 centimeters in length) are always larger than males (which are up to 3.5 centimeters long).
16- Gambusia
Gambusia belongs to the genus of freshwater fish; Has a wide biodiversity, so that about 43 species are known. This aquatic vertebrate has specimens that are under environmental threat, although others are aggressive and invasive in environments alien to theirs.
It can survive extreme conditions of salinity and temperatures reaching 42ºC, although for a short time, apart from areas with little oxygen and seasonal pools. It is in North America and Mexico.
17- Heterandria
Heterandria is not in itself a fish, but a genus of ovoviviparous fish. It is distributed in Central American territory, especially in countries such as Guatemala, Honduras, Belize and Mexico.
They can often inhabit rivers and live in water temperatures ranging from 22 ° to 28.4 ° C, apart from being at altitudes up to 1500 meters above sea level, but prefer water with good oxygenation and a somewhat acidic pH. Approximately nine species are known.
18- Priapella
Priapella is an ovoviviparous fish that belongs to the family of the Pecílidos. It has about five species (Priapella bonito, Priapella chamulae, Priapella compressa, Priapella intermedia and Priapella olmecae) and their habitat is very frequently located between Mexico and the United States (there are some that are in other North American regions).
The males of this vertebrate can have up to 5 centimeters in length, while the females reach even 7 centimeters.
19- Belonesox
The Belonesox is a fish of the Cyprinodontiformes Which tolerates low levels of oxygen in the water, in addition to alkaline waters and high salinity. They are essentially carnivorous and hover around the shallowest water areas.
Its color is usually yellowish, gray and even with orange tones. Females have a gestation of 5 months until they stop up to a hundred fry (which can measure 2 centimeters in length), which feed on zooplankton.
20- Cnesterodon
Cnesterodon is a type of fish that is abundant in the rivers of South America, especially in Uruguay and Brazil. There are nine known species of this animal ( Cnesterodon brevirostratus, Cnesterodon carnegiei, Cnesterodon decemmaculatus, Cnesterodon holopteros, Cnesterodon hypselurus, Cnesterodon iguape, Cnesterodon omorgmatos, Cnesterodon raddai Y Cnesterodon septentrionalis ) And in both males and females is between 2 and 3 centimeters in length.
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