Reproduction among sirenids

[mattias]

My question is about the reproductive mode of member among the family Sirenidae (Siren spp. and Pseudobranchus spp.). Is it inner or outher fertilization we are talking here?

Is there any kind soul out there with up to date information about this? In Ed Kowalsi´s article in the online magazine of Caudata.org there was very interesting and for me new data on this. But unfortunately no final proof.

Are there any other interesting references on this topic?

Petranka´s book from 1998 doesn´t solve the old mystery. I do not have any post-Petranka info on the topic and wonder if there is any new observations made ever since that book.

Most thankful of any information on the subject.

Best regards Mattias Müller

 

[peter]

Mattias, as far as I know, no one knows for sure about the fertilization methods in sirens. Most assume that it's external. Full courtship behavior has never been observed, Ed's article reported more than any other source I've found. There's been relatively little research done on sirens and other aquatic salamanders, so there are huge gaps in known information.

There was a recent study published Dec. 2003 that has lots of interesting information on sirens, but nothing on breeding was learned. If you're interested in the species in general, I think I would be able to send you a copy, ("Population Characteristics, Growth, and Spatial Activity of Siren Intermedia in an Intensively Managed Wetland" by Paul W. Frese)

I've recently obtained some siren intermedia, and I'm going to see if I can learn anything on their breeding activities, so I'll keep you guys posted.

 

[paris]

from shem unger's thesis "sperm production and larval development in hellbenders:a comparison of stable and declining populations" page 5

"only three families of salamanders are known to exhibit external fertilization (cryptobranchidae, hynobidae, and sirenidae)"

from 'biology of amphibians' by w. duellman and l. trueb page 496
"life history- because a spermatheca is absent in females and cloacal glands are absent in males, spermatophores presumably are not produced, and fertilization probably is external"

 

[jim]

I'm new to this site and am looking for information and sites concerning sirens. My 4th grade class and I have two. One 18.5 in. monster in a 20 gal. tank and another smaller and thinner (apprx. 16-17 in) in a 10 gal. Male and female? We hope to find out. Both are almost 5 years old and seem to be in good health. Any of you siren fans have any help to offer?

 

[paris]

jim,
see this link
http://www.caudata.org/forum/messages/8/28922.html?1105251077

 

[edward]

You can also get info here
http://www.caudata.org/cc/species/Siren/S_intermedia.shtml

http://www.caudata.org/cc/species/Pseudobranchus/Pseudobranchus.shtml

Ed

 

[jim]

Ed,Paris, thanks for the sites.