TKS! Re: the first 2 of the 4 new pics, it's rare for my camera to capture a subject in such clear focus from that short of a distance. Sometimes it just...happens!
None of the 4 premmies from the unhealthy sac survived. The ones from the healthy sac are doing fine -- with the possible exception of any that may have been cannibalized, which seems to be often the case with Hynobid larvae. They're growing rapidly so I've had to move them to a larger tank.
I decided to remove the egg sac, which still contains the same number of dud eggs.
After only a week or so since hatching, they're already feasting on tubifex. Brine shrimp are starting to seem too small for them.
Compared with Cynops larvae, their feeding manner is quite aggressive. They frequently target the same worm, and I've intervened several times, worried that the struggle might end up with the bigger larvae cannibalizing the smaller one as an extension of the worm!
When the tubifex ball up, these larvae can exert considerable force to pull individual worms out. Violent little buggers!
I'm now on the lookout for other Hynobid larvae to compare them with. 'Tis the season, after all!