C
chris
Guest
No pics, I'm afraid, but I thought I'd update anyoe interested on the dunni egg sacks I had laid this year, and ask a few questions at the same time.
Although there were only two unfertillised eggs (one in each sack) only a relatively small portion of embryos made it to hatching. All the fertile eggs began development, but there were very high numbers of mutations. Some embryos simply stopped developing early on and died off as the sack decomposed after the others hatched. Of the mutants that continued development, there were two 'forms' of mutation.
The first type (the less distorted of the two) were a translucent grey colour, with overly wide head, no discernible neck area and no properly developed tail. They simply came to a point after the body with a vestigal tail membrane. They were sort of like a partly flattened ice-cream cone. One of these is still alive but i doubt for much longer.
The other mutant form was more severely affected. The larvae were almost entirely transparent, and curled into a C shape, with a shrivelled, thin body which appeared to be missing some of the digestive system (though this varied between individuals). The head was severely malformed and the animals appeared to be unable to eat. The only movement they were capable was a slight wiggle.
All of these are now dead, with only about 3 surviving to hatching. They died once their yolk sack ran out.
The remaining larvae are doing well, eating daphnia, whiteworm and tubifex. They are mostly about 20mm long now, with a few a bit larger and a few quite a bit smaller (15-16mm). I haven't noticed any canibalism as yet.
The fore legs of most individuals are more or less complete now, and the hind legs are starting to grow.
One runty larva died from a gass bubble in the lower intestine.
About 5 larvae have been placed in an established tub outside (with lid!) to see how they do. They seem to have survived up to now and are about the same size as their siblings inside.
So, anyone have any idea why the number of mutants was so high?
Chris
Although there were only two unfertillised eggs (one in each sack) only a relatively small portion of embryos made it to hatching. All the fertile eggs began development, but there were very high numbers of mutations. Some embryos simply stopped developing early on and died off as the sack decomposed after the others hatched. Of the mutants that continued development, there were two 'forms' of mutation.
The first type (the less distorted of the two) were a translucent grey colour, with overly wide head, no discernible neck area and no properly developed tail. They simply came to a point after the body with a vestigal tail membrane. They were sort of like a partly flattened ice-cream cone. One of these is still alive but i doubt for much longer.
The other mutant form was more severely affected. The larvae were almost entirely transparent, and curled into a C shape, with a shrivelled, thin body which appeared to be missing some of the digestive system (though this varied between individuals). The head was severely malformed and the animals appeared to be unable to eat. The only movement they were capable was a slight wiggle.
All of these are now dead, with only about 3 surviving to hatching. They died once their yolk sack ran out.
The remaining larvae are doing well, eating daphnia, whiteworm and tubifex. They are mostly about 20mm long now, with a few a bit larger and a few quite a bit smaller (15-16mm). I haven't noticed any canibalism as yet.
The fore legs of most individuals are more or less complete now, and the hind legs are starting to grow.
One runty larva died from a gass bubble in the lower intestine.
About 5 larvae have been placed in an established tub outside (with lid!) to see how they do. They seem to have survived up to now and are about the same size as their siblings inside.
So, anyone have any idea why the number of mutants was so high?
Chris