Larva, Juvenile, and Adult Stage

The Larva is the first stage of development after being hatched for a graceful decorator crab.  At this stage they are extrememly small and are still developing into their adult form.  Their main source of food is tiny plankton.  They then move into the zoea stage.  The Oregonia gracilis still mainly eats plankton and other small organisms.  By this point they are getting stronger and able to rip apart some organisms.  Once they have reached adult stage they are have full grown pinches and jaws rip food apart and are fully developed so there body can digest more types of organisms.  Graceful decorator crabs are able to eat anything from plankton to other smaller crabs from their same species.  These crabs are classified in the omnivore category because once they become adult crabs they will eat different types of plants, algae, and animals.  Two examples that related to the algae that is eaten by the crab is green algae and blue-green algae Heres a video that will demonstrate the graceful decorator crab eating.


Oregonia gracilis use their pinchers (chelipeds) to obtain food and put into their mouth.  They can only open their mouths so much because of their exoskeleton, which is why the pinchers play such an important role in ripping the prey into small enough pieces to fit into the crabs’ mouth.  Once they food particle is about to entered the mouth it will go through the graceful decorators crabs maxillipeds.  Maxillipeds cover the entire mouth and tare through the food even more to make it smaller and smaller before entering the mouth and jaws.  The food then goes through the esophagus entering the stomach where it gets broken down by the bristles in it.  The next phase is for the food to leave the stomach and digestive juices are released which then the food will digest and absorbed.  The leftover food is sent to the hindgut where it will completely be digested and absorbed.

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