Hello to ALL fellow foldscopers! My name is Nicole and I am a graduate student studying Marine Science at California State University, Monterey Bay. I have been looking at many interesting plants and various critters over the last few weeks in an attempt to refine my foldscope techniques and am ready to share my first post!
Carmel Point at low tide (April 2016)
I visited Carmel Point several weeks ago with my Marine Ecology class to study and sample the intertidal. There were many tide pools and lots of exposed rocky reef harboring various marine organisms. I grabbed a water sample with Golden Rockweed ( Silvetia compressa ) and a couple other different species of algae, not realizing at the time that I had captured the marine critters that live within them.
Tide pool that I collected water from.

Golden Rockweed ( Silvetia compressa ) collected for sampling. Notice the juvenile Rainbow Star ( Orthasterias koehleri ) hanging out between tides.
As I was looking at the water sample I noticed a very small (~1cm) segmented bristle worm, or polychaete, and I’m almost positive it’s the species Nereis virens . They have a proboscis with powerful jaws and eat invertebrates such as crabs and clams, in addition to detrital material. They live in various habitats like mud, mussel beds and the holdfasts of algae, and are active burrowers, but are able to  swim and crawl when needed. Below is a picture I found to show what they look like when not magnified.
Nereis spp . marine worm unmagnified.
I decided to throw it under the scope and my friend Cherisa helped me get a couple pictures and a great video showing its plump body and parapodia (fleshy muscular appendages) with setae (bristle-like hairs).
Nereis spp. eyes, head and beginning of its dorsal blood vessel.

Nereis spp. body region, may be part of the parapodia?
The video below is pretty awesome because you can see its parapodia and setae moving. Also, there are these maroon-red dots that move and we couldn’t figure out what they were?? The linear bright red areas are the dorsal blood vessel and other parts of the circulatory system. I think the dots may be food or other parts of the circulatory system moving through the body… not sure, if you are reading this post and have any insight it would be greatly appreciated!!
Enjoy the video!!
nereis _video