# ovoviviparous, oviparous and viviparous



## swan91 (May 14, 2011)

Hi,
just wondering if anyone can come up with a list of as many australian snakes that reproduce either ovoviviparous, oviparous and viviparous.. there are many sites that state some snakes 'bear live young' but they dont seem to differentiate between viviparous and ovoviviparous snakes..

can anyone list any species? death adders for example? (viviparous or ovoviviparous) anyone have any idea?


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## sookie (May 14, 2011)

I will get back to you after googling all them big words okay.lol


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## $NaKe PiMp (May 14, 2011)

yes death adders and Red bellied Black snake are the two oviviparous species that come to mind where the embryos develop in membranous sacs inside the mother and when ther e ready to hatch the mother gives birth to them and within a 24 hour period the young emerge form the sacs,this is different to viviparous where the young emerge as live snakelets such as in tiger snakes.
These modes are both considered live bearing. but quite often it wont be mentioned when presented with information of a species it will just mention egg laying or live bearing


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## GeckPhotographer (May 14, 2011)

Death Adders ovoviviparous. I cannot find my copy of Australian Snakes, A Natural History, but it would have plenty of information on the topic.


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## swan91 (May 14, 2011)

yea, i was just wondering if there were any other aussie snakes that are oviviparous? I find it interesting as the young and the mother dont exchange nutrients... what other snakes are viviparous? am i right in saying most elapids? or is that too much of a generalization..


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## Waterrat (May 14, 2011)

$NaKe PiMp said:


> yes death adders and Red bellied Black snake are the two oviviparous species that come to mind where the embryos develop in membranous sacs inside the mother and when ther e ready to hatch the mother gives birth to them and within a 24 hour period the young emerge form the sacs,this is different to viviparous where the young emerge as live snakelets* such as in tiger snakes*.



Tiger snakes are also oviviparous and *I think* all Australian elapids are.

Chappell Island tiger snake:

View attachment 200033


_A. praelongus_ - the same:
View attachment 200034


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## $NaKe PiMp (May 14, 2011)

AMS05 said:


> yea, i was just wondering if there were any other aussie snakes that are oviviparous? I find it interesting as the young and the mother dont exchange nutrients... what other snakes are viviparous? am i right in saying most elapids? or is that too much of a generalization..


 


actually there is only 1 snake in the entire world which has shown exchange between mother and developing embryo in form of electrolytes and amino acids
the oviviparous Pseudechis porphyriacus Red Bellied Black snake
I wrote a 30,000 word document on them and this factor was unique to this species


i am just typing a list of Australian snakes vivaporous and ovivaporous just give me a few minutes



Waterrat said:


> Tiger snakes are also oviviparous and *I think* all Australian elapids are.
> 
> Chappell Island tiger snake:
> 
> ...





all Pseudonaja,Oxyuranus,Furina,Demansia,Cacophis,simosulaps,Vermicella and most of Pseudechis are oviparous


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## Waterrat (May 14, 2011)

What I meant was - apart from the oviparous species, the rest of Aussie elapids are oviviparous. Can you think of any Aussie viviparous elapids? I am not looking into any books right now, it's just my thought.


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## $NaKe PiMp (May 14, 2011)

both file snakes are viviparous

Colubrids that are Vivaporous
Bockadom (cerberus rhynchops)

Macleays water snake(Enhydris polylepis)



White bellied mangrove snake (fordonia leucobalia)

Richardsons mangrove snake(Myron richardsoni)




all Australian pythons are oviparous

all blind snakes are oviparous

both species of Krait are oviparous


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## grimbeny (May 14, 2011)

All viviparous vertebrates have some nutrient exchange. This includes respiratory gasses and water but may include ions aswell. Ovoviviparous is an old term that is not used in the scientific literature anymore because it is not well defined. Viviparity includes all species that undergo complete development inside the mother, whereas oviparity includes all species that require some development after the embryos have been laid. The sac that viviparous species may be laid in is actually the embryonic side of the placenta, yes reptiles can have placentas too. If you have ever seen a dog give birth, the babies are usually born in their placental sacs aswell before they emerge. 
Viviparity has evolved twice in the elapids, once in the common black snake and once in the ancestors of death adders, tiger snakes and the sea snakes. There are also many species of Australian elapids that lay eggs.


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## $NaKe PiMp (May 14, 2011)

Waterrat said:


> What I meant was - apart from the oviparous species, the rest of Aussie elapids are oviviparous. Can you think of any Aussie viviparous elapids? I am not looking into any books right now, it's just my thought.


 

yes most tiger snakes are vivaporous as is all copperheads

Densonia
Drysdalia
Echiopsis
hemiaspis
Hoplocephalus
Rhinoplocephalus
Suta
Tropidechis

all viviparous as far as i know the only Ovivaporous is P.porphyriacus ,all Acanthopis,
and obviously chapell island tiger as per your picture
i am not sure if there is other Ovivaparous but i am going to have a look as it is intersting


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## Waterrat (May 14, 2011)

I can't figure it out. In your first sentence you're saying "yes, most tiger snakes are viviparous" (which they're not, what do you mean by "some"?) and then in the end you're saying that they are oviviporous????????
By the way, it's "vivi....", not "viva...."


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## grimbeny (May 14, 2011)

I would like to see what definition for ovoviviparity you guys are using.


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## $NaKe PiMp (May 14, 2011)

grimbeny said:


> I would like to see what definition for ovoviviparity you guys are using.


 
Ovoviviparity as in born in thin membranous sacs that are retained in the mother until they are ready to hatch



Waterrat said:


> I can't figure it out. In your first sentence you're saying "yes, most tiger snakes are viviparous" (which they're not, what do you mean by "some"?) and then in the end you're saying that they are oviviporous????????
> By the way, it's "vivi....", not "viva...."



sorry abut spelling mistake i spelt it wrong once ina all my above posts 

and we have both been spelling Ovoviviparity wrong lol

Some snakes are born in the membranous sacs and others wriggle free of the mother free of any soft shelled egg such as seas snakes.

Adders and Red belllied black are born still with in the thin membranous sacs as is your chappell island tigers which they stay in for a few hours.
I was under the impression copperheads and other tigers are not deposited within these membranous sacs


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## grimbeny (May 14, 2011)

$NaKe PiMp said:


> Ovoviviparity as in born in thin membranous sacs that are retained in the mother until they are ready to hatch


 
Are dogs ovoviviparous aswell then?

All live bearing vertebrates are contained within membranous sacs in the uterus, we call this the embryonic portion of the placenta. This includes humans. Whether a species' embryos are ruptured before or after birth is not worth a reproductive mode classification. 

This is an old but good paper that covers the topic:
Blackburn, D. G. (1992). Convergent evolution of viviparity, matrotrophy, and specializations for fetal nutrition in reptiles and other vertebrates. American Zoologist, 32(2), 313-321.


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