Invertebrates
Flatworms
Ribbon Worms
Round Worms
Arrow Worms
Segmented Worms
Bryozoans
Phoronids
Lamp shells
Bilateral symmetry, three tissue layers
Incomplete digestive tract: gut without anus
Bilateral symmetry with complete digestive tract; nervous system
Larval stages of Anisakis are found in fish and can be passed to humans if raw (or undercooked) fish is consumed.
Long, elastic body with proboscis, a long tube used to entangle prey (mostly worms and small crustaceans)
Complete digestive tract with mouth and anus
Transparent, streamlined body with fish-like fins and tail
Voracious predators; they swim in rapid, darting movements to capture prey (small planktonic crustaceans, fish larvae, and other plankton).
Body cavity is a coelom, which is lined with tissue derived from mesoderm, as in higher animals.
Closed circulatory system
Bryozoans (together with phoronids and brachiopods) possess a unique feeding structure called a lophophore, ciliated tentacles surrounding the mouth
Some are encrusting, others form small fan- or tree-shaped colonies.
Suspension feeders
Circular or horseshoe-shaped lophophore
Worm-like, living in tubes of sand grains
Two shells enclosing body
Coiled lophophore