a late Pilidium larva

Franz Neidl · Post by **Franz Neidl** » Tue Oct 18, 2011 1:45 pm

The Pilidium larva is a stage of the Ribbon worms (Nemertine) helping them to a better dispersal in the sea.
The picture shows a late state of the larva, which was about 400 µm high.
You can see also the future animal - specially in the second picture. "The young worm grows within the still existing ectodermal structures of the larva, which may continue to feed in the plankton. Its metamorphosis proper takes place when the juvenil worm breaks out of it larval container, often ingesting the larval remnants" (Larink O., W. Westheide: Coastal Plankton. Photo Guide for European Seas, München, 2006, p.64).

Obj. 20x DIC, without eyepiece
Obj. 40x DIC, without eyepiece

Franz

Wim van Egmond · Post by **Wim van Egmond** » Wed Oct 19, 2011 1:11 am

Very nice Franz,

isn't it amazing that it almost looks like a human embryo?

Wim

Mitch640 · Post by **Mitch640** » Wed Oct 19, 2011 4:47 pm

It must be absolutely maddening to only see a tiny window of time in the complete cycle of these creatures. I am just a hobbyist and it's bad enough, I can't image what a researcher goes through.