The longest running Amphibian Community on the Internet.

Tags Register FAQ Calendar Search Today's Posts Mark Forums Read Caudata.org Store

Notices

Hynobiid Salamanders (Hynobiidae) This group of Far Eastern salamanders are becoming increasingly popular in captivity, and thanks to the captive breeding efforts of one European hobbyist in particular (you know who I mean), they are becoming easier and easier to acquire.

Reply

 

Thread Tools Display Modes
Old 21st April 2007   #1
jennifer
Guest
 
Posts: n/a
Gallery Images:
Comments:
Default

I obtained 6 CB juvenile H. tokyoensis about 6 months ago. I believe that all looked similar at the time I received them, but now one of them is much larger and lighter colored. The other 5 still look very similar.

Is it likely that the large one is female, and the others male? Or is it possible that there was a mix-up and the large one is H. dunni (which was part of the same import)? Or is it possible that they will all become lighter colored as they grow up, and this one is simply the "porker" of the bunch?

Click the image to open in full size.



  Reply With Quote
Old 21st April 2007   #2
cameron
Guest
 
Posts: n/a
Gallery Images:
Comments:
Default

I don't know but I think it has to do with age. Some sals like P. ruber loose their bright color as they get older. Just a guess.Click the image to open in full size.



  Reply With Quote
Old 21st April 2007   #3
Tim Johnson
(TJ)
Site Contributor
 
Join Date: Oct 2002
Nationality:
Location: [ Members Only ]
Posts: 4,471
Gallery Images: 0
Comments: 0
Rep: TJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.org
Default

Jen, it seems to me that most of your juvenile H. tokyoensis are still showing their typical juvenile pattern and coloration, while the "porker" is either a bit older or has simply developed faster. Were the all the same size when you got them? Juveniles of most if not all hynobiid species of eastern and northern Honshu look pretty much the same to the casual observer, being speckled like that all over the dorsum (including H. tokyoensis, H. lichenatus, H. nigrescens). Then over time the speckles fade away from the top part of the dorsum but speckling of a sort remains on the lower part of the sides.

I'm not aware that coloration is any way of determining sex -- usually one goes by body size and shape, tail shape, and appearance of the cloaca (though I'm no good at this). As you can see by the following picture, there's quite some variation in H. tokyoensis coloration even among those gathered in the same pond during breeding season.

Click the image to open in full size.
(this is an old photo that I'd posted before)

As for telling male hynobiids apart from females, it's always best to wait for the breeding season when differences are most apparent. Here's something to refer to (though not strictly as the species are different from H. tokyoensis):

http://www5d.biglobe.ne.jp/~hasumi/photo/vent_e.html

http://www5d.biglobe.ne.jp/~hasumi/p...aquatic_e.html

http://www5d.biglobe.ne.jp/~hasumi/photo/fem_e.html

http://www5d.biglobe.ne.jp/~hasumi/p..._cloaca_e.html

(Message edited by TJ on April 21, 2007)



TJ is offline   Reply With Quote
Old 21st April 2007   #4
Ryan
(ryan)
Prolific Member
 
Join Date: May 2007
Nationality:
Location: [ Members Only ]
Posts: 989
Gallery Images: 0
Comments: 0
Rep: ryan has started on the right path
Default

Wow they really can vary!



ryan is offline   Reply With Quote
Old 21st April 2007   #5
Michael Shrom
(michael)
2010 Research Grant Donor
 
michael's Avatar
 
Join Date: Apr 2003
Nationality:
Location: [ Members Only ]
Posts: 3,220
Gallery Images: 0
Comments: 0
Rep: michael is considered an Authority at Caudata.orgmichael is considered an Authority at Caudata.orgmichael is considered an Authority at Caudata.orgmichael is considered an Authority at Caudata.orgmichael is considered an Authority at Caudata.orgmichael is considered an Authority at Caudata.orgmichael is considered an Authority at Caudata.orgmichael is considered an Authority at Caudata.orgmichael is considered an Authority at Caudata.orgmichael is considered an Authority at Caudata.org
Default

If I remember correctly the juvenile tokyoensis and dunni look similar but act different. I think the tokyoensis are the jumpy ones. I'm 95% sure you have all tokyoensis.



michael is offline   Reply With Quote
Old 23rd April 2007   #6
jennifer
Guest
 
Posts: n/a
Gallery Images:
Comments:
Default

Thank you for all the good info, Tim!Click the image to open in full size. I remember that photo, but had never given any thought to the color variation among the animals. I think my porker may simply be headed toward being one of the lighter colored ones. At this point, he/she is very different looking from the others, but I think it's just a size difference. I haven't tried to examine cloacas, but I suspect it's too soon to tell a difference; those photo links are excellent.



  Reply With Quote
Old 23rd April 2007   #7
Tim Johnson
(TJ)
Site Contributor
 
Join Date: Oct 2002
Nationality:
Location: [ Members Only ]
Posts: 4,471
Gallery Images: 0
Comments: 0
Rep: TJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.orgTJ is a well respected, valued and knowledgeable member of Caudata.org
Default

Sure thing Click the image to open in full size.

And as Michael suggested, there are behavioral differences. Put a worm in front of its mouth and if it immediately grabs the worm and swallows it down like there's no tomorrow, it's probably an H. dunni. If it's skittish to begin with and reacts cautiously to being hand-fed, it's probably an H. tokoyoensis ... though I suppose H. tokyoensis become "tamer" over time (I've never kept adults, just raised some from egg sacs to the juvenile stage and given them away).

As for those links, yeah, they're nice. I wasn't aware before that the cloacal opening changes from a slit into a hole before egg sacs are laid. I wonder if this applies to all members of Hynobius...



TJ is offline   Reply With Quote
Reply

Tags
dimorphism, sexual, tokyoensis


(View-All Members who have read this thread : 19 (Set)

454, BMOC, caudatadude28, Chamaeleo, Chinadog, damien, Endemico, FrankSar, GeoNewt, Goods, Molch, paps8, RobM, santa, Sebas2000, skyler, sojot, vipera, yellowman4005
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads

Thread Thread Starter Forum Replies Last Post
Sexual mature of axolotls Atl Axolotl General Discussion 2 16th June 2007 03:09
After sexual interference (C. e. ensicauda larvae) henk Fire-Belly & Sword-Tail Newts (Cynops & Hypselotriton) 9 22nd February 2007 20:20
Sexual interference in Cynops ensicauda henk Fire-Belly & Sword-Tail Newts (Cynops & Hypselotriton) 7 13th January 2007 18:40
Sexual Maturity brendan Axolotl General Discussion 2 17th February 2005 12:16
Sexual Maturity? jacob Newt and Salamander Help 1 25th January 2005 04:37


All times are GMT. The time now is 17:33.