Gastrotrichs

Phylum Gastrotricha

These are microscopic animals. They are mainly aquatic, although some can be found in soil.

Reference

http://eol.org/pages/8728/overview

Lamp Shells

Phylum Brachiopoda

So called because some of them look like lamp. They are marine filter feeders. They can be mistaken as molluscs, which have left and right shells, instead of the brachipods' top and bottom shells.

Reference

http://eol.org/pages/1498/overview

Moss Animals

Phylum Bryozoa

These are microscopic animals. So called because they look like moss on rock.

Reference

http://eol.org/pages/2060/overview

Horseshoe Worms

Phylum Phoronida

So called because in some of them, the tentacles look like a horseshoe. These are marine filter-feeding worms.

Reference

http://eol.org/pages/8867/overview

Ribbon Worms

Phylum Nemertea

Called Ribbon Worms as they are usually long and thin. Also known as Proboscis Worms, so called for their proboscis.

Reference

http://eol.org/pages/2855/overview

Rotifers

Phylum Rotifera

These microscopic animals mainly exist in water, such as ponds.

Reference

http://eol.org/pages/6851/overview

Peanut Worms

Phylum Sipuncula

They look like peanut pods when they retract, hence the name. They are common along coasts.

Reference

http://eol.org/pages/8871/overview