Hi Henk, congrats on your success. That's a lot of larvae! I'm looking forward to seeing the pics. Maybe you can start a snow-white strain!
As for retardatus, I wish I had some basis for comparison but I have only that one larvae. There were a couple more in the shop, but they were all similar. I'll try to post a pic that's a bit clearer/brighter than those above.
Also on the Hynobius front, I just sent away 20+ Hynobius nebulosus morphs to a local enthusiast by special refrigerated (not frozen!) delivery service. That's lightened my load a bit, but nobody here seems to want my H.tokyoensis morphs (too common?). I wouldn't mind keeping 6 or so but not 30+! Also managed to unload around 10 of my 20 or so H.dunni larvae, the interesting thing about them being that they are still haven't morphed since hatching over 6 weeks ago and are twice as large as my nebulosus and tokoyoensis morphs.
On the downside, I lost one of my precious 3 new Onychodactylus japonicus larvae to a power-failure-related temperature rise last week. I've decided to move them into the vegetable compartment of my fridge (IF my girlfriend consents...) rather than maintaining my current setup, which involves cooling the living room (i.e. newt room) to around 20C and then lowering the tank temp to 18C using a fan directed at the water surface. I've been using an overflow filter with them as I'd heard they require a current, but I now hear that's not necessarily the case if the temp is cool enough. Same goes for kimurae and other such Hynobiids that don't inhabit still water, or so I hear.
Do you use any filtration or apply any kind of water current with your fridge-cooled sal larvae?
Cheers!