What are the main structures you can observe when you remove the exoskeleton of the abdomen of a crayfish?

Since only Phylum Arthropoda have exoskeletons, it would depend on which creature you were specifically looking at. For ex, in a grasshopper you would see the stomach, the large intestine, muscle...

It is the Abdominal Muscles and the Itestine.

If you opened the abdomen of a crayfish you would see the intestine , flexor muscle and extensor muscle

The large feathery structures are the gills.

What are the main structures you could have observed if you had removed the exoskeleton of the abdomen? What are the main structures you could have observed if you had removed the exoskeleton of the...