Several days ego I found this animal in the seaplancton. It was the first time in my life and I was very surprised. Is it a fish or not a fish? I studied my books and I discovered that is a very known animal in all textbooks of biology: the larva of Branchiostoma lanceolatum (syn. Amphioxus) from the Acrania. This animal is an ancestor of the vertebrates and therefore it is studied now a lot in genetics and evolution studies.
Brightfield, objective 4x, 3 pictures.
The third picture is made with polarized light in order to have a better view of the structure (the Neural cord and the Notochord).
Franz Neidl
