Mosquito larva - my first polarized darkfield

[spongepuppy]

Thanks to esteemed forums member Cactusdave, I've learned that a cheap retarder can be made using cellotape and a microscope slide.

Using this newfound technology, I was able to view a mosquito larva's peripheral nervous system in some detail using my bodged ATC2000 polarized light / darkfield setup:



And a short video:
http://www.flickr.com/photos/spongepuppy/13057684775/

I shot the image sequence with the intention of stacking it, but there was too much movement. The video is only a few seconds long, but it does show some great internal detail (and the coverglass crushing the specimen).

Also, some shots of nerves at 40x:


Very excited to try this technique out (and to refine it somewhat).

[Cactusdave]

Nice pictures. I think the branched structures looking a bit like nerves in your pictures may in fact be branches of the tracheal system of the larva which distributes oxygen to the muscles. I would be interested to see the comments of someone more familiar with the structure of larval insects on this.

I have visualised structures, which I think may be nerves, with associated ganglia connected to the gut in the phantom midge, Chaoborus, larvae, but they look different to these and need X40 DIC to see them clearly.

[spongepuppy]

Given my limited grasp of arthropod anatomy (and my near total inexperience in observing it), I'm inclined to suspect you're right!

In any case, I think I need to work on specimen prep, because this one was pretty badly ruptured by the addition of the coverslip. Not squishing the specimen would probably assist in identifying the right structures, after all.